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2 Contact Hours including 2 Pharmacology Hours
This peer reviewed course is applicable for the following professions:
Advanced Registered Nurse Practitioner (ARNP), Certified Registered Nurse Anesthetist (CRNA), Clinical Nurse Specialist (CNS), Licensed Practical Nurse (LPN), Licensed Vocational Nurses (LVN), Midwife (MW), Nursing Student, Registered Nurse (RN)
This course will be updated or discontinued on or before Tuesday, March 1, 2022

Provide an overview of obesity and explain the healthcare professional's role in preventing and treating obesity.


At the completion of this activity, the learner will be able to:

  1. Recognize the incidence of obesity in America
  2. Describe five medical conditions that are associated with obesity
  3. Use body mass index to classify obese patients
  4. Describe three lifestyle changes that aide in weight loss
  5. Describe the patients who qualify for medical or surgical interventions for obesity
CEUFast Inc. did not endorse any product, or receive any commercial support or sponsorship for this course. The Planning Committee and Authors do not have any conflict of interest.

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To earn of certificate of completion you have one of two options:
  1. Take test and pass with a score of at least 80%
  2. Reflect on practice impact by completing self-reflection, self-assessment and course evaluation.
    (NOTE: Some approval agencies and organizations require you to take a test and self reflection is NOT an option.)
Author:    Raymond Lengel (MSN, FNP-BC, RN)


Greater than one-third of the adult population in the United States is obese. Obesity increased from 15.0% in the late 1970’s to 35.7% in 2012.1 Non-Hispanic blacks have an obesity rate of 49.5 percent, Mexican Americans have a rate of 40.4 percent, and non-Hispanic whites have a rate of 34.3 percent.1 In 1991 only 4 states had obesity rates greater than 15%. In 2010, no state had an obesity rate less than 20%.1

Obesity is not a cheap disease; it is estimated that obesity costs the United States 147 billion dollars a year and the annual medical costs for obese individuals are 1,429 dollars higher than those who have a normal body weight.1

The Obesity Epidemic

Our culture is inundated around food; most social events revolve around food, high calorie foods can be found in most work places and a fast food restaurant is on almost every corner. While fast food in itself is not the main determinate of obesity, our choices contribute to obesity. A meal consisting of a hamburger, small fries and a diet soda is about 500 calories. Unfortunately, a more characteristic meal includes a double cheeseburger, large fries and a large soda, which equals 1450 calories.

Obesity is just not for adults, children are obese as well. The generation of kids that are being raised today may have shorter life spans than their parents. Kids are exposed to obesity and the medical consequences associated with that obesity. Children eat poorly, a habit that is the result of not only their parents, but also the previous generation and society in general. Obesity is a form of malnutrition.


Being overweight or obese is being at a weight that is more than what is considered healthy. It increases the risk of many diseases, reduces quality of life and increases risk of death.

Classification of being overweight and obese are determined by using the weight and height to calculate the body mass index (BMI), which is a method used by healthcare providers to define risk of body weight. Generally, for adults, the BMI correlates with the amount of body fat. It is not a perfect system, as it does not directly measure body fat. For an individual with a large amount of muscle mass the equation will overestimate the amount of fat. This equation will underestimate body fat for those with significant muscle wasting.

The BMI utilizes a mathematical formula to classify patients as underweight, normal body weight, overweight and obese. Obesity is defined as having a body mass index of thirty or higher. Body mass index is determined by dividing the weight in kilograms by your height in meters squared (Table 1).

Table 1: Body Mass Index
Interpretation of Body Mass Index
UnderweightLess than 18.6
Obese30 or more
Morbidly Obese40 or more
Case Study 1

John, a 42 year-old man, weighs 200 pounds or 90.9 kilograms and is 5 feet and 9 inches or 1.75 meters. His waist measures 35 inches, his hips measure 33 inches and his neck measures 15.5 inches

What is his body mass index? What is his waist to hip ratio?

To determine his body mass index use the following formula

Weight in kilograms/((Height in meters) x (Height in meters))


John has a body mass index of 29.7, which places him in the overweight category.

His waist-to-hip ratio is simply calculated by dividing 35/33 which equals – 1.06 which places him at high risk as it is above 0.9. John has the typical apple shape indicating he has abdominal obesity which is linked to many negative health effects including: diabetes, hypertension, and dyslipidemia.

The following are on-line BMI tools:

More sophisticated measures of body fat exist but there is no data to show where death and disability rates are increased with anything other than BMI. Abdominal obesity is the most harmful type of fat and measuring the amount of fat in the abdomen in an important method for determining risk from excessive body fat. Fat on the trunk is more problematic than fat on the legs, arms or hips. Fat around the waist is more biologically active. It secretes inflammatory proteins and is linked to plaque deposits in the coronary arteries.

The measurement of abdominal obesity can be done in a number of ways. The most precise is to image the trunk with a method such as magnetic resonance imaging, which is an accurate way to measure intra-abdominal fat. This is impractical in most settings as it is a costly method. A more common way to determine the degree of abdominal obesity is measuring the circumference of the abdomen. Waist circumference of greater than 40 inches in men and 35 inches in women is associated with an increase risk of disease.

The waist-to-hip ratio is another way to determine risk. The number is obtained by dividing the waist circumference by the hip circumference. If the waist-to-hip ratio is greater than 0.9 in men or 0.8 in women than the patient is at increased risk for obesity related complications.

Those with a large waist-to-hip ratio are said to have an “apple shape”. This describes a situation when there is more weight in the abdomen and a “pear” shape is when there is more weight in the hips. Apple shapes are at higher risk for hypertension, heart disease and diabetes compared to pear shapes.

Neck circumference should also be evaluated as it predicts obesity and sleep apnea. Those with neck circumferences of greater than 36 cm in diabetics and 37 cm in non-diabetics are likely to suffer from central obesity.2Men with a neck circumference of greater than 17 inches and women with a neck circumference greater than 16 inches are at risk for sleep apnea.3

Cause of Obesity

When energy intake is greater than energy output the body stores the extra energy as fat. Energy intake is simply the amount of energy you put in your body in the form of food and drink. The amount of energy individuals expend per day is variable and is dependent on multiple factors including, age, sex, amount of muscle mass, genetic factors, existing disease states, ambient temperature, and activity level.

One pound of energy is equal to 3500 calories. In order to gain one pound of fat, an excess of 3500 calories needs to be created. For example, if someone has had stable weight over one year and then adds a new routine of eating one cookie, which is equivalent to 100 calories, than in 35 days that individual would gain one pound. This assumes that every thing else stays stable.

Many societal factors are strongly related to obesity. Long-work schedules keep people away from active lifestyles. Large portion sizes are the norm at many restaurants and encourage overeating which increases calorie intake. Lack of access to healthy food and easy access to junk food is another factor. Many work places have vending machines with chips, candy bars and sodas. Sporting events have snack bars with foods like nachos, popcorn, beer and soda instead of healthier options. The abundance of high calorie food is common at restaurants, work places, parties and in many homes.

Americans are sedentary. People are more involved with spectator sports than participating in sports. Extra calories consumed that are not expended are stored as fat.

Chronic sleep deprivation may promote weight gain due to the effects on the body's physiology and people's behavior. In addition to weight gain, sleep deprivation is associated with adverse cardiovascular events, glucose intolerance and decreased leptin levels. Leptin is a hunger-suppressing hormone and signals satiety to the hypothalamus and, thereby, reduces fat storage and energy intake. It also affects energy intake to prevent weight gain. In addition to the effects of leptin, those who are sleep deprived are awake and have more opportunity to eat, often times at night in front of the television.

Genetics are also related to obesity. Genes have a strong influence on the propensity to be overweight or obese and also affects the location and the amount of fat that one stores. Dopamine, a brain chemical that helps make eating and other behaviors more rewarding, is related to consumption of food and may be genetically lower in some people.

Families also share food and activity habits, which link the environment to weight. Parents who have an abundance of fruits and vegetables in the house and minimal high calorie junk food in the house tend to have children who eat better than a household with an abundance of chips, doughnuts and ice cream.

Certain health conditions increase the incidence of obesity. Hypothyroidism, Cushing’s disease, depression and polycystic ovarian syndrome increase the chance of obesity. Medications such as selective serotonin reuptake inhibitors antidepressants, tricyclic antidepressants, antipsychotics, some anti-convulsants, lithium, insulin, sulfonylureas, and corticosteroids increase the incidence of weight gain.

Negative Implications of Obesity

Obesity is associated with increased mortality and morbidity. The risk of disease increases with increasing levels of BMI and abdominal fat. The cut-off is a BMI of 25.0 kg/m2. When levels exceed 30 kg/m2 than risk is significantly increased.

Obesity increases the risk for heart disease, stroke, high blood pressure and abnormal cholesterol.4 Obesity is associated with an increased risk of cardiovascular disease at least partly because of worsening effect it has on its risk factors: dyslipidemia and hypertension, but an independent effect of obesity on heart disease.

Cerebrovascular accidents are more common in obese patients. Many of the same risk factors associated with heart disease are related to stroke. High blood pressure, abnormal cholesterol, abnormal blood clotting and glucose intolerance are all part of the reason stroke rates are higher in obese individuals.

Obesity increases risk for type II diabetes.4 It does this by decreasing the body’s ability to use insulin in a condition called insulin resistance. Insulin, a hormone produced by the pancreas, is used to help get the sugar that circulates in the blood into the cells. As the insulin resistance does not allow the glucose to enter the cells optimally the level of blood glucose rises. This increased blood sugar signals the brain that glucose is not getting into the cells, because of the insulin resistance. The brain responds by setting up a system to release more insulin and glucose, thereby further increasing the amount of glucose and insulin in the blood. Insulin resistance is common in obese individuals and is strongly correlated with abdominal fat, as opposed to fat stored in the legs and hips. High levels of insulin and sugar in the blood have toxic effects on many body systems including the eyes, heart, nerves, and kidneys. Insulin resistance is associated with increased risk for blood clotting which increase the risk of vascular disease including heart attacks and strokes.

Not only does obesity tax the heart and hormonal system but also it negatively affects other body systems. Excess body weight puts stress on the joints and leads to an increased risk, incidence, and severity of osteoarthritis. Obesity is associated with functional impairments, such as the inability to bend over to pick up an item off the floor and negatively impacts quality of life. Obesity increases the incidence of gout with the risk being higher in those who are heavier.

Obese individual have an increased incidence of gallbladder disease, gastroesophageal reflux, erosive esophagitis, and cancer of the esophagus. Symptoms of GERD are correlated with BMI. Gallstones and gallbladder disease are more common in overweight and obese individuals.4

Non-alcoholic fatty liver disease is another complication of obesity and presents with damage to the liver that looks like alcohol damage but in the absence of alcohol abuse. It is often associated with metabolic syndrome and insulin resistance. Weight loss typical improves insulin resistance and non-alcoholic fatty liver.6

Obesity also increases the incidence of kidney, endometrial, breast, colon, rectal, pancreatic, and esophageal cancer.5 Obesity is associated with a 98% increased risk of prostate cancer.

Other conditions are associated with obesity. Obesity significantly increases the risk for sleep apnea as fat stored around the neck impedes breathing. Obesity weakens the immune system and makes it harder for obese patients to fight infections. Data from mice indicates that obesity interferes with the immune systems ability to respond to certain organisms. Stress incontinence, leaking of urine during sneezing, laughing or coughing, is associated with obesity.

Surgery is more risky in obese patients than those of normal weight. The obese patient has greater surgical risk and more postoperative complications, such as delayed wound healing, infection, deep venous thrombosis, pulmonary embolism, and pneumonia.

Obesity affects mood. Abdominal obesity significantly increases the risk of depression and anxiety.6 Depression and obesity feed off one another. Depression lowers self-esteem and makes weight loss harder.

Table 2 – Diseases Associated with Obesity



Glucose intolerance, insulin resistance and diabetes


Heart failure

Heart disease





Obstructive sleep apnea

Gall bladder disease

Increases risk of certain cancers

Gastroesophageal reflux disease

Non-alcoholic fatty liver disease

Positive Benefits of Weight Loss

To combat the negative impact of obesity, people need to lose weight or maintain a healthy weight. Weight loss can be accomplished through diet, lifestyle modifications including exercise, medication, or surgery. Not everyone needs to lose weight. If the body mass index is in the ideal range, maintenance of that body weight along with eating a well balanced diet will help maintain good health. Maintaining an optimal body weight is not the only factor to good health. Many alcohol abusers have an ideal body weight but have poor nutritional status. Eating a healthy diet along with maintaining an optimal body weight are keys to staving off illness and preventing functional decline.

Weight loss is associated with a decrease in blood pressure, improved insulin sensitivity, increased high-density lipoprotein levels and decreased triglycerides. Loss of excessive body weight will reduce strain on the joints and improve osteoarthritis symptoms. Weight loss has the potential to uplift sprits, improve mood and reduce depression/anxiety. It can reduce the incidence of GERD and gallbladder disease. Weight loss improves quality of life and should increase life expectancy.

Patient Assessment

The healthcare system does a poor job in the evaluation of obesity. The way healthcare professionals think about obesity and the way the system is set up needs to change for the system to handle this problem effectively. Healthcare professionals typically tell patients they need to lose weight and do not spend time discussing strategies or making referrals for their patients to be successful. A system needs to be built that will help clinicians more easily address and get paid for the treatment of obesity.

A recent study (Miller, Alpert & Cross, 2008) that surveyed registered nurses showed that nurses had an average body mass index of 27.2 and almost 54% were classified as overweight or obese. Over one in two nurses lack the motivation to make healthy lifestyle changes and four out of ten are unable to lose weight even with a healthy diet and regular exercise. Only one in four nurses use the body mass index to make clinical judgments of body weight. Most alarming, almost every nurse is aware that being overweight is dangerous, but more than three in four nurses do not address body weight in patients who are overweight or obese.

The first aspect of the evaluation of obesity should be a history. Medical history should be reviewed to determine what diseases might be causing, contributing to or complicating obesity. Important diseases to look for include depression, eating disorders, and endocrine disease. Evaluation of all co-morbidities is part of the patient history. A complete dietary history is helpful which should be done with the help of a registered dietitian. Evaluation of body weight changes, lifestyle habits and exercise patterns are important to ascertain.

Assessment of obesity includes evaluation of height and weight and determining the BMI. Classify the patient into one of the categories for body weight (Table 1). It is also essential to get an abdominal circumference and a waist-to-hip ratio. Measure the neck circumference as this determines risk for sleep apnea.

The skin should be examined. Hirsutism is excessive or increased hair growth where it typically does not occur. In women, hirsutism may indicate polycystic ovarian disease. Intertriginous rashes may be a complication of obesity. Acanthosis nigricans, which is characterized by thick, dark, velvety skin often on the neck or in the armpits, may point to insulin resistance.

The abdomen should be evaluated for an enlarged liver which may suggest nonalcoholic fatty liver disease. The heart and lung assessment should look for any abnormality such as hypertension, cardiomegaly, or respiratory disease. When examining the extremities, search for joint deformities, evidence of osteoarthritis, and any pressure ulcerations.

After the disease is diagnosed and quantified the healthcare provider needs to consider what is causing the obesity. Is there a disease present? Is there a medication contributing to the disease? Or is it purely a lifestyle issue?

Diseases that need to be considered include: hypothyroidism, Cushing syndrome, eating disorders such as binge eating disorder, depression, and anxiety. Rare genetic diseases may be related to obesity, such as Turner’s syndrome or Prader-Willi syndrome.

Complications of obesity should be sought out. Complications often associated with obesity include heart disease, hypertension, dyslipidemia, diabetes, sleep apnea, gastroesophageal reflux disease, gallbladder disease and non-alcoholic fatty liver disease.

Part of the evaluation needs to be look at the motivation of the patient. Determining why weight loss is desired can help the clinician understand which interventions will be helpful and how aggressive treatment should be. A history of previous weight loss attempts can help determine the most effective treatment. Determining how much time the patient has will help in determining which plan will be helpful in the treatment of disease. Does the patient work a 70-hour work schedule or do they sit around the house all day watching television? Determine if the patient has a support network of family and friends. Make sure that the patient understands the risks, benefits and expectations of the weight loss plan prescribed.


Treatment should be initiated with a BMI above 25 if there are two or more of the following risk factors:

  • large waist circumference
  • high blood pressure
  • dyslipidemia
  • family history of diabetes or heart disease

If the BMI is greater than 30 then treatment should be initiated regardless of number of risk factors. Irrespective of weight or risk factors all people should be encouraged to live a healthy lifestyle.

Goals of weight loss should include a gradual reduction in body weight that can be maintained over the long-term and a reduction in risk factors. Weight loss of one to two pounds a week is ideal. Individual goals, motivation, and medical co-morbidities need to be considered when setting goals.

Treatment options are to increased physical activity, dietary changes, behavior therapy, medications, surgery or a combination of these techniques.

Dietary Changes

Weight loss will occur if someone finds a lifestyle that expends more calories than it consumes. As long as the individual sticks to it, it will work. A big problem with dieting is that individuals do not comply with this strategy over the long haul. Many fad diets are available, and many are effective. As long as they stick to the principle of fewer calories in and more calories out.

Dietary changes are a cornerstone to an effective weight loss program. Reducing the number of calories to less than the number of calories expended, creates a negative calorie balance and will result in weight loss. While it goes against the norm in American culture, where people want things now, the ideal weight loss program would include eating a healthy diet that would result in a slow and steady weight loss while improving the nutritional content of the diet.

Many diets are available for weight loss including: low-calorie, low fat, low-carbohydrate, balanced, and many fad diets. Most diets have some proven efficacy, at least in the short term. Low-calorie diets are classified as diets of between 800-1200 calories per day while normal-calorie diets are greater than 1200 calories. General dietary recommendations include selecting a diet that incorporates between 1000 and 1200 calories per day for women and 1200 to 1600 calories per day for men. Normal calorie diets will not induce a rapid weight loss but they provide the benefit of allowing the patient to develop a healthy eating pattern while losing weight. Very-low calorie diets, often less than 800 calories per day, typically involve specialized foods or drinks that do not teach skills necessary for the maintenance stage of the weight loss.

Healthy Normal-Calorie Diet

Nutritional status has an immense impact on not only weight but on maintaining health, disease progression and patient healing. Good diets incorporate variety and are composed of lots of fruits and vegetables, whole grains and lean meats. A proper balance of carbohydrates, proteins and fats is a key factor to a healthy diet. A normal-calorie diet focuses on eating healthy foods to maintain an optimal weight while creating a negative calorie balance. The next few paragraphs discuss what constitutes a healthy diet.

The Dietary Guidelines for Americans 201514:

  1. Follow a healthy eating pattern across the lifespan.All food and beverage choices matter. Choose a healthy eating pattern at an appropriate calorie level to help achieve and maintain a healthy body weight, support nutrient adequacy, and reduce the risk of chronic disease.
  2. Focus on variety, nutrient density, and amount.To meet nutrient needs within calorie limits, choose a variety of nutrient-dense foods across and within all food groups in recommended amounts.
  3. Limit calories from added sugars and saturated fats and reduce sodium intake.Consume an eating pattern low in added sugars, saturated fats, and sodium. Cut back on foods and beverages higher in these components to amounts that fit within healthy eating patterns.
  4. Shift to healthier food and beverage choices.Choose nutrient-dense foods and beverages across and within all food groups in place of less healthy choices. Consider cultural and personal preferences to make these shifts easier to accomplish and maintain.
  5. Support healthy eating patterns for all.Everyone has a role in helping to create and support healthy eating patterns in multiple settings nationwide, from home to school to work to communities.

The guidelines recommended eating a variety of fresh fruits and vegetables, whole grains, low-fat proteins and healthy fats. For weight loss they recommend aiming for a reduction in total energy intake while maintaining nutrient intake and increasing physical activity.14

Carbohydrates should constitute 45-65 percent of total calories. Not all carbohydrates are created equally. Foods that are high in simple carbohydrates including white bread, white rice, ice cream, candy, soda and jellies, are absorbed very quickly and cause rapid rises in blood sugar. Simple carbohydrates are not packed with essential vitamins, minerals and healthy chemicals like complex carbohydrates. Complex carbohydrates include whole grain cereals, beans and many vegetables are more densely packed with vitamins, minerals and fibers. The bulk of the diet should be consumed from complex carbohydrates including fruits, vegetables and whole grains.

Fiber, another carbohydrate, is an essential food element to prevent disease. It is recommended that 14 grams of fiber is eaten for every 1000 calories consumed which equates to approximately 25 grams of fiber per day for women and 38 grams a day for men. Interestingly, Americans only eat on average 15 grams of fiber a day.14 Fiber is found in fresh fruits and vegetables, bran cereals, and beans. Eating a diet high in fiber has multiple benefits including preventing constipation, possibly reducing the risk of colon cancer, aiding in weight loss, improving cholesterol readings and slowing the absorption of sugars.

Protein should make up 10-35 percent of the diet. While many people advocate a high protein diet, they do not result in any greater weight loss than a moderate protein level. Some experts suggest that a diet high in protein results in more satiety and leads to increased compliance with a low calorie diet. High levels of protein have the potential to put extra strain on the kidneys.

Fat should make up 20-35 percent of the diet and a small percentage should be saturated fat. Partially hydrogenated fats - as found in margarine, crackers, cookies, doughnuts, and chips - are particularly harmful to the body’s cholesterol. Monounsaturated fats, polyunsaturated fats and omega-3 fats should be substituted for saturated fats. Monounsaturated fats are found in avocado; olive, canola and peanut oils. Polyunsaturated fats are not as healthy as monounsaturated fats but are better than saturated fats and are prevalent in soybean and corn oil. Omega-3 fats are found in certain fish including mackerel, salmon, and albacore tuna.

Water is vital to live. It is recommended that one drinks 64 ounces of water a day. Benefits of drinking water include less constipation, reduction in fluid retention and flushing the body of unnecessary substances. Those who drink water before meals often eat less during the meal. In addition, cold water may increase weight loss by elevating energy expenditure.

A healthy eating pattern includes:

A variety of vegetables from all the subgroups—dark green, red and orange, legumes (beans and peas), starchy, and other

  • Fruits, especially whole fruits
  • Grains, at least half of which are whole grains
  • Fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages
  • A variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products
  • Oils

A healthy eating pattern limits:

  • Saturated fats and transfats, added sugars, and sodium

Key Recommendations that are quantitative are provided for several components of the diet that should be limited. These components are of particular public health concern in the United States, and the specified limits can help individuals achieve healthy eating patterns within calorie limits:

  • Consume less than 10 percent of calories per day from added sugars
  • Consume less than 10 percent of calories per day from saturated fats
  • Consume less than 2,300 milligrams (mg) per day of sodium
  • If alcohol is consumed, it should be consumed in moderation—up to one drink per day for women and up to two drinks per day for men—and only by adults of legal drinking age.

Evidence shows that healthy eating patterns, as outlined in the Guidelines and Key Recommendations, are associated with positive health outcomes. The evidence base for associations between eating patterns and specific health outcomes continues to grow. Strong evidence shows that healthy eating patterns are associated with a reduced risk of cardiovascular disease (CVD). Moderate evidence indicates that healthy eating patterns also are associated with a reduced risk of type 2 diabetes, certain types of cancers (such as colorectal and postmenopausal breast cancers), overweight, and obesity. Emerging evidence also suggests that relationships may exist between eating patterns and some neurocognitive disorders and congenital anomalies.

According to the Dietary Guidelines for Americans carbohydrates should constitute 45-65 percent of total calories.14 Not all carbohydrates are created equally. Foods that are high in simple carbohydrates including white bread, white rice, ice cream, candy, soda and jellies, are absorbed very quickly and cause rapid rises in blood sugar. Simple carbohydrates are not packed with essential vitamins, minerals and healthy chemicals like complex carbohydrates. Complex carbohydrates include whole grain cereals, beans and many vegetables are more densely packed with vitamins, minerals and fibers. The bulk of the diet should be consumed from complex carbohydrates including fruits, vegetables and whole grains.

Fiber, another carbohydrate, is an essential food element to prevent disease. It is recommended that 14 grams of fiber is eaten for every 1000 calories consumed which equates to approximately 25 grams of fiber per day for women and 38 grams a day for men. Interestingly, Americans only eat on average 15 grams of fiber a day.14 Fiber is found in fresh fruits and vegetables, bran cereals, and beans. Eating a diet high in fiber has multiple benefits including preventing constipation, possibly reducing the risk of colon cancer, aiding in weight loss, improving cholesterol readings and slowing the absorption of sugars.

Protein should make up 10-35 percent of the diet. While many people advocate a high protein diet, they do not result in any greater weight loss than a moderate protein level. Some experts suggest that a diet high in protein results in more satiety and leads to increased compliance with a low calorie diet. High levels of protein have the potential to put extra strain on the kidneys.

Fat should make up 20-35 percent of the diet and a small percentage should be saturated fat. Partially hydrogenated fats - as found in margarine, crackers, cookies, doughnuts, and chips - are particularly harmful to the body’s cholesterol. Monounsaturated fats, polyunsaturated fats and omega-3 fats should be substituted for saturated fats. Monounsaturated fats are found in avocado; olive, canola and peanut oils. Polyunsaturated fats are not as healthy as monounsaturated fats but are better than saturated fats and are prevalent in soybean and corn oil. Omega-3 fats are found in certain fish including mackerel, salmon, and albacore tuna.

Water is vital to live. It is recommended that one drinks 64 ounces of water a day. Benefits of drinking water include less constipation, reduction in fluid retention and flushing the body of unnecessary substances. Those who drink water before meals often eat less during the meal. In addition, cold water may increase weight loss by elevating energy expenditure. One study showed that obese children who drank 10 mL/kg/day of cold water may lose an additional 1.2 kg per year.

Small quantities of bad food are not necessarily harmful but should be avoided in large quantities. Foods that should be avoided in large quantities include: foods high in sugar and empty in calories, high in trans fat and high in saturated fat. Foods high in sugar and empty in calories include candy and regular soft drinks. Trans fat is found in many processed foods such as chips, cookies, and crackers. Saturated fats are found in fatty red meats, butter and fried food such as most French fries.

Medically Supervised Diets

Structured diets under the supervision of healthcare professionals are another trend in today’s weight loss armamentarium. These diets are typically very-low calorie (400-800 calories per day) and offer rapid weight loss. Because these diets are so low calorie there are risks. Loss of lean mass is common and can be combated by adding a resistance-training program. Gallstone formation, electrolyte imbalance and dehydration are risks and are a main reason that they are medically supervised. Other risks with this diet include hair loss, hypothermia and skin thinning. These diet centers often incorporate a physician, registered dietitian and psychologist. They provide very tightly controlled diets and often have a weight loss of 1.5-2.5 kg/week.12

Multiple factors need to be considered when evaluating very-low calorie diets. Initial weight loss in these diets is often high because of the loss of water and muscle mass. This will stabilize out after a short period of time. Men tend to lose more weight partly because they have more muscle mass.

Low-Carbohydrate Diets

Low-carbohydrate diets are one of the more popular diet methods and they work well. Low carbohydrate diets contain between 60 and 130 grams of carbohydrates and very low carbohydrate diets contain less than 60 grams of carbohydrates a day. When carbohydrates are restricted to less than 50 grams of carbohydrates a day, ketosis will develop and significant amount of weight can be lost. This weight loss consists of significant water and lean tissue loss.

Unfortunately, many questions remain unanswered, especially in respect to long-term safety and efficacy of low carbohydrate diets. Low carbohydrate diets typically incorporate high protein animal foods, which are usually also high in saturated fat; this theoretically increases the risk of coronary heart disease, diabetes, stroke and several types of cancer. Excessive protein intake increases the risk of osteoporosis as well as kidney and liver disorders.

Considering the energy in/energy out equation that explains weight loss, low carbohydrate diets that restrict calories will result in weight loss. Some data points to the low carbohydrate diet as slightly better in their ability to result in weight loss, at least in the first 6-12 months. One study compared a low fat diet that restricted calories, a Mediterranean diet and a low-carbohydrate diet that did not restrict calories over a two year period. The low carbohydrate diet resulted in a 4.7 kg weight loss, the Mediterranean diet had a 4.4 kg weight loss and the low fat diet had a 2.9 kg weight loss. The low carbohydrate diet also resulted in the most positive effects on the lipid profile with reduced triglycerides and increased high density lipoproteins (HDL). The Mediterranean diet was most effective at improving glycemic control in diabetics.

A large analysis compared four diets including a low fat, calorie restriction diet; a very low carbohydrate diet (Atkins diet); a balanced glycemic load diet (Zone diet); and a very low-fat diet (Ornish diet). The study showed that the very low carbohydrate diet led to the most weight lost - 4.7 kg over 12 months. Weight loss in the other diets was not statistically different and averaged about 2.0 kg. The very low carbohydrate diet group also had the most favorable effects on HDL cholesterol and triglycerides. Adherence to the diet was the most important factor that predicted weight loss.

While many studies show that low carbohydrate diets may have the most positive effects on short term weight loss, long term weight loss effectiveness has not been established.

Overall, low carbohydrate diets are better than low fat diets at improving HDL and lowering triglycerides, but have similar effects on total cholesterol and low density lipoproteins. The overall effect on cardiovascular risk is similar between low fat and low carbohydrate diets. Low carbohydrate diets are more frequently associated with side effects such as constipation, headache, muscle cramps, diarrhea, rashes and weakness.

Sub-sets of patients may do better on a low carbohydrate diet. Certain characteristics, such as those who spike higher insulin levels after a glucose load, may predict who does better on a low carbohydrate diet. At the present time there is not enough data to accurately predict who will do well on a specific type of diet. The best combination of macronutrients depends on individual factors.

The key to lasting weight loss is long-term lifestyle modification. This means changes that last a lifetime not just changes that result in a ten-pound weight loss in the first couple weeks (which is mostly just water). Changing eating and exercise habits by eliminating the junk, adding healthy choices and adding daily or almost daily exercise is the only way to have long-term weight loss. Dietary adherence is a critical factor in weight loss maintenance.


The second part of the energy in/energy out equation is to increase the number of calories expended daily by participating in physical activity. Exercising and burning calories can have tremendous benefit in regard to weight loss but also has benefits outside of weight loss. When comparing normal weight individuals who are fit to unfit individuals, unfit individuals have two times the risk of death regardless of their BMI. In addition, fit individuals who are obese or overweight have similar death rates when compared to normal weight individuals who are fit.7

A recent analysis recommends that in addition to dietary changes, incorporating an exercise program is critical to a successful weight loss or weight maintenance program. Moderately intense exercise between 150 and 250 minutes per week will lead will lead to modest weight loss. This translates to a minimum of thirty minutes of activity five days a week. Physical activity of greater than 250 minutes a week is associated with significant weight loss. In addition, weight maintenance is optimized with physical activity greater than 250 minutes a week. Using a pedometer can be helpful in shedding extra pounds. Pedometers get people to walk more, serve as a motivating factor and are an effective strategy for weight loss.

Resistance training should also be included into any weight loss program. Resistance training improves muscular strength and endurance, but also helps preserve lean muscle mass. Dieting, especially very-low calorie diets, are associated with a loss of muscle mass. Resistance training can ameliorate the loss of lean tissue. In addition, weight-training increases muscle mass.

Muscle mass is more metabolically active and results in a higher daily energy expenditure. For example, John weighs 200 pounds, of that, 140 pounds is lean muscle. His daily energy expenditure is measured at 2800 calories a day. After two months of weight and endurance training his weight is now 195 pounds, but his lean mass is 145 pounds. Not only has he actually lost 10 pounds of fat, but also his energy expenditure is now 2850 calories a day. This may not seem like a lot, but over the course of one year that is an extra 18,250 calories burnt. If his diet stays the same he will potentially lose an extra 5 pounds without having to do anything but maintain that muscle mass. Individuals with more muscle, burn more energy through out the day, including while watching TV and while sleeping.

American culture wants things now but poor health and obesity is something that occurred over the years and reversing this process will not occur overnight. It takes a lifetime commitment. While the reversal of disease and obesity is a slow process, weight loss will improve mental and physical function.

Table 3: Key points for weight loss
  • To lose weight, eat fewer calories that you expend.
  • Know your body mass index and what your weight goal is.
  • Utilizing the principals in the exercise section and engage in a safe and effective exercise program.
  • Maintain a healthy diet with plenty of fruits and vegetables, complex carbohydrates, low fat dairy and lean protein sources.
  • Reduce the quantity of saturated fat in the diet.


Medications can be used to treat obesity, when lifestyle changes alone do not provide the necessary weight loss. Prescription weight-loss drugs are meant for those with a BMI greater than 30 or above 27 with obesity-related conditions, such hypertension, type 2 diabetes, dyslipidemia or sleep apnea.

Not all medications are effective for all patients. The healthcare provider needs to monitor effectiveness and if there is not a desirable weight loss of two kilograms over the first month, then therapy should be reconsidered. Changing medications, adjusting the dose or discontinuing are all options. It is important to determine if the risk of medication is worth the benefit of using the drug. Most side effects of these medications are mild and often improve with continued treatment. Rarely, serious and even fatal outcomes have been reported.

Weight loss drugs come with a long history of complications. In the past, thyroid medication was used to increase metabolism and led to cases of hyperthyroidism. Many of these cases led to death as this was done at a time when there were not effective treatments for hyperthyroidism. Amphetamines are used as weight loss aids but have led to addiction in many patients. Most recently fenfluramine and dexfenfluramine, more popularly known as phen/fen, were associated with valvular heart disease and primary pulmonary hypertension.

Patients need to have realistic expectations about the efficacy of weight loss medications. Medications are more effective in some patients than others. Three medications are approved for weight loss – orlistat, lorcaserin and phentermine-topiramate. In addition, there are four appetite suppressants that are sold under multiple different names – phentermine, benzphetamine, diethylpropion and phendimetrazine.

Orlistat (Xenical, Alli), which is available as a prescription and over the counter, decreases the body’s ability to absorb dietary fat by about one-third. It blocks the enzyme lipase, which breaks down dietary fat. Consequently, the body takes in less fat and less calories.

Cramping, gas, abdominal pain, diarrhea and leakage of oily stool are potential side effects of orlistat. Eating a low-fat diet can minimize side effects. Deficiencies of fat-soluble vitamins are a potential side effect of this medication and taking a multivitamin two hours before or after taking the drug is recommended.

Orlistat is a good first line options as it is effective and is safe. Orlistat is approved for up to four years of use, but is often used longer in patients who are doing well.

Many benefits beyond weight loss have been shown with orlistat. One study used 120 mg of orlistat three times a day along with lifestyle changes and showed that after four years the risk of type 2 diabetes significantly decreased and weight loss (10 kg vs. 6 kg) was significantly better than lifestyle alone.

Orlistat has been shown to improve blood pressure in obese patients. A recent study showed that it lowered systolic blood pressure by 2.5 mm Hg and diastolic blood pressure by 1.9 mm Hg.13

In addition, orlistat improves cholesterol levels with a reduction in total cholesterol of 4 to 11 percent and a reduction in low density lipoprotein levels of 5 to 10 percent.

Lorcaserin (Belviq) is thought to reduce food intake and promote satiety. It was approved in 2010 and is dosed 10 mg twice a day. Research has shown that weight loss is 3 to 4 kg more in those who take lorcaserin when compared to placebo.8 Lorcaserin also reduces blood pressure, total cholesterol, low density lipoprotein levels, insulin levels, fasting glucose and C - reactive protein.8 Lorcaserin is often used in those who do not tolerate orlistat, but less safety data is available with this medication.

Side effects include: nausea, headache, back pain, dizziness and upper respiratory tract infections. There is a small risk of valvulopathy in those on lorcaserin. It should not be used in pregnancy and in those with a creatinine clearance of less than 30 ml/min. It interacts with other drugs that affect the serotonin system (most antidepressants).

Phentermine-topiramate (Qsymia) was approved in 2012 and is more effective than orlistat or lorcaserin, but side effects are more problematic. Common side effects include: constipation, dry mouth, paresthesias, depression, anxiety, reduced attention, and a slight increase in heart rate. It is contraindicated in those with glaucoma or hyperthyroidism and should not be used in those with cardiovascular disease. Use cautiously those with a history of renal stones. It has the potential to lead to some fetal malformations and should be used very carefully, if at all, in women of childbearing age.

Over one year this medication leads to an 8 to 10 kg weight loss compared to 1.4 kg weight loss for placebo.9 In a similar study, after 56 weeks of treatment - placebo led to a 1.9 kg weight loss; phentermine-topiramate dosed at 3.75/23 mg resulted in a 6 kg weight loss; and the 15/92 mg dose resulted in a 12.6 kg weight loss.10

It is prescribed at 3.75/23 mg for 2 weeks than titrated to 7.5/46 mg. After 12 weeks the dose may be increased to 11.25/69 mg for 2 weeks than 15/92 mg every day. If after 12 weeks at the maximum dose a five percent weight loss does not occur the medication should be weaned. Stopping the topiramate abruptly may lead to seizures.

Appetite suppressants are a popular type of medication for weight loss. These include: phentermine, benzphetamine, diethylpropion and phendimetrazine. Phentermine is the most popular in the United States. These medications suppress the appetite and are FDA approved for up to 12 weeks.

Appetite suppressants are associated with multiple problems including many side effects and the potential for abuse. Common side effects include: dry mouth, insomnia, headache, anxiety, restlessness, tachycardia, shortness of breath, dizziness, nausea and bowel changes. These medications should not be used in those with hyperthyroidism, glaucoma, heart disease, hypertension, history of drug abuse or those under 17 years old. Appetite suppressants have been shown to lead to a 0.5 pound weight loss per week over placebo.8


Surgery is usually reserved for those with a BMI of greater than 40. This threshold is lowered to a BMI of 35 if one is afflicted with an at risk conditions such as sleep apnea, diabetes or heart disease The FDA recently approved an adjustable gastric band for patients with a BMI of 30 or more who are also afflicted with an obesity related condition such as diabetes or heart disease. In addition, the patient should accept the risks of the surgery and be willing to commit to lifelong healthy eating and exercise.

In the United States, four types of operations are used in the management of obesity including vertical sleeve gastrectomy, Roux-en-Y gastric bypass, an adjustable gastric band, and biliopancreatic diversion with a duodenal switch.

The vertical sleeve gastrectomy limits the amount of food taken into the body and reduces the amount of food used. This procedure uses staples and a band to create a long vertical tube or banana-shaped stomach. The procedure removes most of the stomach. The procedure also results in a reduction in the hormone ghrelin that lowers appetite.

Roux-en-Y gastric bypass is the most commonly performed weight loss surgery in the United States. This is a combined restrictive procedure and malabsorptive procedure. The restrictive part involves creating a small pouch in the stomach to restrict food intake. To reduce the number of calories absorbed, a section of the small intestine, which is Y shaped, is attached to the pouch, so food bypasses the stomach, duodenum, and the part of the jejunum. This reduces the number of calories that are absorbed.

The adjustable gastric band is done via laparoscope by placing a silicone rubber band around the upper end of the stomach. The banding makes a small pocket and a thin passage to the stomach. An access port is placed so the band can be made more loose or tight with an infusion of saline.

The biliopancreatic diversion with a duodenal switch is a complex procedure. It removes a large part of the stomach, similar to vertical sleeve gastrectomy, to restrict the amount of food able to be consumed. In addition, the small intestine is modified leading to a limited ability of the duodenum to absorb food and vitamins. This procedure also modifies bile and other digestive juices which affects digestion and the absorption of food. While this procedure may lead to a large amount of weight loss, it has the potential to lead to many problems such as anemia, osteopenia or osteoporosis.

Bariatric surgery is very effective. Among those with type 2 diabetes, bariatric surgery results in a significantly greater weight loss when compared to non-surgical means of weight loss with a mean difference of 26 kg.11

Acute complications of these procedures include: infection, bleeding, peritonitis, diarrhea, deep vein thrombosis and pulmonary embolism. Long-term complications often include malabsorption of vitamins and minerals leading to vitamin deficiencies, abdominal strictures and hernias.

Vitamins and minerals not absorbed well include: vitamin B (vitamin B9 [folic acid] and B12 [cobalamin]), iron, copper, zinc, and calcium. If the surgery diverts the food from the biliary and pancreatic system then the fat-soluble vitamins (A, D, E and K) are not absorbed well.

Hernias may include: incisional hernias or internal hernias. An incisional hernia is a weakness that protrudes from the abdominal wall through a surgical incision; this is less common when a laparoscope is used. An internal hernia occurs when the bowel is trapped in the lining of the abdomen.

Another problem is the dumping syndrome. This happens after eating a meal high in carbohydrates. Food moves too quickly into the small intestine resulting in abdominal pain, nausea, weakness, sweating, bloating and dizziness.

Weight loss is often accomplished quickly. While benefits may be great, anytime surgery is considered it must be done carefully as it is associated with risks and complications. Long-term success after surgery is related to the individual lifetime commitment to behavioral changes. Without continually working on the lifestyle changes the patient will not get the full benefit from the surgery.

After bariatric surgery the diet should be modified to prevent complications from the surgery. Careful adherence with the surgeon’s recommendations is critical. Referral to a dietitian may also be indicated to assist in eating healthy and safely (especially in the first few months). Some recommendations include:

  • Eat a low calorie diet with balanced meals
  • Consume small portions
  • Initially keep calories low (less than 600 calories a day) which will be gradually increased
  • Eat slowly
  • Avoid foods that are not chewed easily: steak, pork, rice, raw vegetables and fresh fruits
  • Chew all food thoroughly
  • Do not use straws and do not drink carbonated beverages – these may introduce air in the GI tract and cause discomfort
  • Drink water and non-caffeinated low calorie beverages between meals
  • Minimize or completely avoid alcohol as it is absorbed very quickly
  • Consume high protein foods – try to get at least 65 grams a day
  • Pills/vitamins that are taken may need to be cut into small pieces to allow them to be absorbed
  • Supplements are recommended after surgery including (but not limited to) a high potency multivitamin, calcium supplement (1200 to 2000 mg a day divided, preferably as calcium citrate); vitamin D supplement (800-1000 international units day); and vitamin B12 (500 mcg day).
Case Study 2

Kristen K. is a 33 year-old white female who is 5 feet 6 inches tall and weighs 306 pounds. Her body mass index is 51.5 and has a waist measurement of 54 inches and a hip measurement of 58 inches for a waist to hip ratio of 0.93. She suffers from hypertension, osteoarthritis of her hips and knees, diabetes and sleep apnea. Her medications include: lisinopril 40 mg a day, hydrochlorothiazide 50 mg a day, metformin 1000 mg twice a day, NPH insulin 40 units in the morning and 20 units before dinner, and hydrocodone/acetaminophen as needed for pain.

She weighed 280 pounds three years ago and has slowly gained weight despite multiple attempts at lifestyle changes including exercise and diet as well as a trial of medications. She used orlistat 120 mg three times a day for 6 months, but gained 5 pounds while on this medication. Her compliance was poor with orlistat due to frequent oily stools and staining of her clothes. She attempted to use lorcaserin but had significant nausea while on this medication. Her physician was reluctant to use phentermine-topiramate due to her hypertension.

Because of her co-morbidities, her unsuccessful attempt at lifestyle changes and medications she was referred to a surgeon.

The surgeon decided to perform a Roux-en-Y gastric bypass. The procedure was performed without any complications. Over the next year Kristen lost 60 pounds and cut her insulin dose in half and was able to reduce her hydrochlorothiazide to 25 mg a day. Over the next year, with the initial weight loss, Kristen was able to significantly increase her physical activity and was able to lose another 50 pounds. Her insulin and hydrochlorothiazide were discontinued. In addition, her lisinopril dose was reduced to 20 mg a day and she no longer needed any hydrocodone/acetaminophen for her osteoarthritis.


Obesity is a key problem affecting the American healthcare system. It is associated with many common, chronic diseases and reduces quality of life. Nurses have a key role in helping the healthcare system identify obese patients, educate them and implement interventions to reduce obesity.

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  1. Center for Disease Control. (2013). Adult Obesity Facts. Retrieved February 3, 2018 from (Visit Source).
  2. Aswathappa J, Garg S, Kutty K & Shankar V. (2013). Neck Circumference as an anthropometric measure of obesity in diabetes. North American Journal of Medical Science. 5(1), 28-31.
  3. MayoClinic. Sleep Apnea. (2013). Retrieved February 4, 2018 from (Visit Source).
  4. Center for Disease Control. (2012). Overweight and Obesity. Retrieved February 4, 2018 from (Visit Source).
  5. National Institute of Diabetes and Digestive and Kidney Disease. (2012). Do you know the health risks of being overweight? Retrieved February 8, 2018 from (Visit Source).
  6. Hryhorczuk C, Sharma S & Fulton SE. (2013). Metabolic disturbances connecting obesity and depression. Frontiers in Neuroscience. 7, 117.
  7. Barry VW, Baruth M, Beets MW, Durstine JL, Liu J, & Blair SN. (2014). Fitness vs. Fatness on All-Cause Mortality: A Meta-Analysis. Progress in Cardiovascular Disease. 56(4), 382-90.
  8. Bray, G. A. (2014). Drug therapy of obesity. Retrieved February 3, 2018 from (Visit Source).
  9. Gadde KM, Allison DB, Ryan DH, Peterson CA, Troupin B, Schwiers ML & Day WW. (2011). Effects of low-dose, controlled-release, phentermine plus topiramate combination on weight and associated comorbidities in overweight and obese adults (CONQUER): a randomized, placebo-controlled, phase 3 trial. Lancet. 377(9774), 1341-52.
  10. Allison DB, Gadde KM, Garvey WT, Peterson CA, Schwiers ML, Najarian T, Tam PY, Troupin B & Day WW. (2012). Controlled-release phentermine/topiramate in severely obese adults: a randomized controlled trial (EQUIP). Obesity (Silver Spring). 20(2), 330-342.
  11. Gloy VL, Briel M, Bhatt DL, Kashyap SR, Schauer PR, Mingrone G, Bucher HC & Nordmann AJ. (2013). Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomized controlled trials. BMJ. 347, f5934.
  12. Hamdy O. (2013). Obesity Treatment & Management. Retrieved February 8, 2018 from (Visit Source)
  13. Siebenhofer A, Jeitler K, Horvath K, Berghold A, Siering U & Semlitsch T. (2013). Long-term effects of weight-reducing drugs in hypertensive patients. Cochrane Database Syst Rev. 3:CD007654.
  14. U.S. Department of Agriculture and U. S. Department of Health and Human Services. (2015). Dietary Guidelines for Americans 2015. Retrieved Feburary 18, 2018 from: (Visit Source)