Counsel Patients on “Weight Loss For Life” To Prevent Obesity Effects

Patients seek physician direction on diet, exercise and therapy

By Adrian T. Harvey, DO

Few diseases that present to the family practice office are not affected by obesity in some way. Even in its mildest forms, overweight patients often are affected by diabetes, hypertension, and dyslipidemia. Complications such as cancer, nonalcoholic fatty liver disease, and pulmonary disease are associated with increased levels of obesity (see figure 1).

The prevalence and effects of obesity are so widespread in the United States that many experts agree we are in the midst of an evolving obesity epidemic. Since the 1960’s, surveys of the United States population have been conducted by government agencies and other health organizations to evaluate, among other diseases, the prevalence of obesity.

The data obtained and analyzed in the National Health Examination Surveys (NHES) and the National Health and Nutrition Examination Surveys (NHANES) reveal increasing trends in overweight or obese patients (see figure 2). According to their data, nearly two-thirds of all Americans are overweight (Body Mass Index >25) and nearly one-third are obese (Body Mass Index >30).1 It is estimated that health care costs related to overweight and obesity are approximately $117 billion.2

Efforts in preventive medicine could and should be addressing means to reduce obesity and its effects. Family practice physicians and other specialists alike are in a position of great influence in reducing morbidity and mortality associated with obesity. Patients often seek direction regarding why it can be so difficult to lose weight, and perhaps more importantly, how to keep lost weight from returning.

Weight Gain Factors
When patients and their families are closely followed, it becomes apparent that there are many who are more prone to being overweight or obese than others. There is evidence in the medical literature to substantiate this observation. Management of weight is based upon principles of caloric intake and expenditure. Nonetheless, differences in genetic makeup of some patients may contribute to their success at efforts to manage their weight.

Studies of Pima Indians have demonstrated that several factors affecting this population lead to an increased tendency to gain weight.3 First, these patients have a low resting metabolic rate. Second, these patients tend to have a low level of spontaneous physical activity. Finally, they have demonstrated a low ratio of fat oxidation to carbohydrate oxidation.

Rice et al. demonstrated that certain genes in a population of French Canadians may affect fat mass and resting metabolic rate3. Other genes that also may affect fat mass were demonstrated in Mexican Americans by Comuzzie et al. and the magnitude of Body Mass Index (BMI) was shown to be possibly linked to a gene in Pima Indians by Price et al.3

More recent attention in the media has been paid to Leptin and its relationship to weight gain. Leptin is a peptide that was originally identified in mice and later in humans. In one model studied, deficiencies in Leptin led to hyperphagia and subsequent morbid obesity. These mice also demonstrated poor growth and infertility secondary to gonadal hypofunction.

Mice found to be deficient in the Leptin receptor demonstrated similar characteristics. When the Leptin deficient mice were given supplements of the protein, a significant decrease in food intake, increased weight loss and greater skeletal growth was observed.4

Humans deficient in plasma Leptin demonstrate early-onset obesity, increased food consumption, hyperinsulinemia, hypogonadism, defective function of the hypothalamo-pituitary thyroidal pathway, and defects in T-cell function and number.5

The targets of Leptin in the brain are referred to as proopiomelanocortin (POMC) and neuropeptide Y receptors. They are found in the greatest concentration in the hypothalamus where centers regulating appetite are located.5 This observation may explain the hyperphagia found in Leptin deficient animals, including humans.

After the discovery of Leptin and its receptors, investigators administered supplemental Leptin to patients deficient in the protein. The major observation was a normalization of hyperhagic tendencies. Caloric intake decreased by as much as 84 percent. Patients also showed appropriately timed pubertal development without inducing precocious puberty. Free T4 levels also increased throughout treatment.5

While preliminary results of these studies have been promising in the treatment of obese patients, it is important to note that the samples of patients studied in these investigations are very small. Another pertinent fact is that weight loss tended to taper off and these patients required increasing doses of Leptin during treatment, likely due to the development of antibodies to the protein.
Because these studies consisted of very small numbers of subjects, it is important to recognize these genes may or may not be found in much subsets of patients. Nonetheless, evidence exists that there are multiple genetic determinants of obesity. Finally, the possibility of pharmacologic therapies to treat theses patients may be available in the future.

Weight Loss Tactics
It seems there are a large number of experts and methods for losing unwanted weight. Diets found in popular literature, on television, or on the internet claim, “Eat all you want and still lose weight” or, “Melt the fat away-while you sleep!” Others are described by adjectives such as “Breakthrough”, “Easy”, “Fast”, “Guaranteed” or “Miracle Cure”. In a recent query through Google®, when the phrase “Weight loss” was queried, 76,400,000 results were found. The word “Diet” revealed 172,000,000 entries. It is no wonder patients are often confused as to what method is best to lose weight.
Family physicians can provide significant assistance to patients attempting to manage weight with a few simple principles that are based upon the tenet that the modality used to lose weight should be similar to the method used to maintain a healthy weight.

Caloric Intake Versus Energy Expenditure
Most experts agree that weight management is governed by a very simple rule illustrated by maintaining energy balance (see figure 3). In order for a patient to lose weight, energy expenditure must outweigh energy or caloric intake.

Patient education can be easily accomplished utilizing tools that illustrate balance and expenditure of energy. (See figure 4). The most important principle for patients to understand is that the goal of increased energy expenditure to lose weight and balancing energy intake versus expenditure for weight maintenance should be a life long goal and not just a temporary effort until their weight goals are met.

Physical Exercise
The principle that greater energy expenditure leads to greater long-term weight loss was demonstrated in a study conducted by Jeffery et al. In this study, 202 patients were randomized into two groups, one with a standard energy expenditure goal of 1000kcal/week versus another group with a goal of high physical activity comprised of 2500 kcal/week. As one might expect, those in the high physical activity group lost significantly more weight at 12 and 18 months (8.5 and 6.7 kg versus 6.1 and 4.1 kg respectively) than those in the standard energy expenditure group.6

Commercial Versus Self-Help Programs
One question commonly asked about weight loss is which sort of program works best, a commercial program such as Weight Watchers or a do-it-yourself program in which the patient directs their own weight loss efforts. In order to answer this question, Heshka and researchers conducted a multicenter, randomized study conducted over two years in which 423 patients with body mass indices ranging from 27 to 40 kg/m2 were followed for 26 weeks in either a commercial program (Weight Watchers) or a self-help program7. Those assigned to Weight Watchers attended the program’s group meetings and followed their set eating guidelines, whereas patients assigned to the self-help program met twice with a nutritionist and were given a supply of printed materials and commonly used weight loss resources.

The results from this study were enlightening. Those enrolled in the Weight Watchers arm of the study exhibited significantly greater decreases in body weight (-4.8 versus -1.4kg), and body mass index (-1.7 versus -0.5 kg/m2) than those in the self-help arm. A mean decrease in waist circumference (-4.3 versus -0.7 cm) and fat mass (-3.8 versus -1.5 kg), were also observed in the Weight Watchers patients compared to those in the self-help arm.7

One other interesting endpoint of the study was the greater decrease in the mean serum homocysteine levels of patients randomized to the commercial program versus those in the self-help arm of the study (-0.5 versus 0.9 microM).

The authors of the study concluded that those patients who enrolled in a commercial program such as Weight Watchers were more likely to lose weight than those patients who received brief counseling and self-help efforts, and that weight loss can lead to a decrease in markers of heart disease.

Evaluating Current Programs
There exists a seemingly endless amount of proprietors marketing their diet method to patients. Most programs are based on differing amount of energy sources, such as fats versus carbohydrates (see table 1).

An article in the Journal of the American Medical Association reported results of a comparison of four of these diets8. A total of 160 patients were randomized to one of four diets. These patient’s mean body mass index was 35 kg/m2 with a range of 27-42 kg/m2. Patients enrolled also had known risk factors of hyperlipidemia, hypertension, or fasting hyperglycemia. The results of the study are shown in table 2.

As indicated in table 2, all diets produced weight loss and corollary decreases in body mass index, waist circumference, and levels of LDL cholesterol among other markers of cardiovascular disease. Surprisingly, there was no significant difference in the amount of weight lost by these patients.

What was significant was the level of adherence to each diet related to weight lost. The greater the adherence, the greater amount of weight lost by respective patients. The authors of the study suggested that adherence to a diet correlated with how extreme the diet was perceived to be. For example, adherence to the Weight Watchers diet, which prescribes caloric restriction with a variety of foods, was greater than adherence to the Atkins model, incorporating very low carbohydrate intake with increased protein and fat ingestion.

Thus, the more popular diets on the market produce similar results but differ in the ability of patients to follow them over extended periods of time. The more moderate the diet in terms of “allowed” foods, the more likely the patient was to adhere to the diet and the more likely to lose weight.

Medical Therapy
In more severe cases of obesity pharmaceutical therapy may be an option for treatment. These medications are approved for those with a body mass index of 30 kg/m2 of for patients with obesity-related conditions, such as hypertension, dyslipidemia, and type 2 diabetes, with a body mass index greater than 27 kg/m.2 Several types of medications exist for the treatment of obesity (see tables 3 and 4).

Most of these drugs are classified as appetite suppressants which act as dopamine, serotonin, and norepinephrine reuptake inhibitors. Other types of drugs include lipase inhibitors which decrease lipid absorption. The newer medications are approved for long-term use compared to older drugs, which are approved for short-term use less than one month.

Use of these weight loss medications leads to an average decrease in weight of 2.3 to 10 kg. Studies have shown that weight loss with some medications may decrease blood pressure, and decrease cholesterol and triglyceride levels.9 Long-term use of these drugs may also help keep lost weight off as well.9

As with all medications, patients should be warned of potential adverse effects. Orlistat may produce gastrointestinal symptoms such as cramping or discomfort, flatulence, diarrhea, and leakage of greasy stools. These side effects can be mild and temporary, but often are exacerbated with foods with high fat content. Also, patients taking Orlistat should be counseled to take a multivitamin at least two hours before or after taking the drug because of potential interference with dietary vitamin absorption. 9

Patients taking Sibutramine may notice increased heart rate and blood pressure as well as headache, dry mouth, constipation, and insomnia9. Because of the cardiovascular effects of this drug, it should not be prescribed to patients with poorly controlled hypertension or heart disease.

Bariatric Surgery
For those patients with the most severe cases of obesity, gastric bypass surgery may be considered. Patients with body mass indices of 40 kg/m2 or greater or 35 kg/m2 or greater with obesity-related conditions such as type 2 diabetes, heart disease or sleep apnea may be candidates for surgical intervention.

These procedures are of two types, restrictive and a combination of restrictive and malabsorptive reconstruction of the gastrointestinal system. Restrictive procedures include adjustable gastric banding and vertical gastric banding in which a hollow rubber band, or band and staples are used to greatly reduce the dimensions of the stomach and subsequent volume capacity to induce a feeling of fullness with smaller food quantities.

Advantages to the banding techniques include the possibility of being performed laparoscopically, with less morbidity and recovery time for the patient. The disadvantages of these procedures are that patients who undergo banding surgery lose less weight and are less likely to maintain the weight loss than those undergoing combination procedures.

At ten years after surgery, as few as 20 percent of patients will be successful in keeping off the weight which they lost as a result of the surgery. Most patients gain weight by eating soft foods which pass through the pouch created by the stomach banding. Risks of the procedure include vomiting secondary to overeating, and slippage of the rubber band as well as infection or bleeding.10

The more common procedure performed today for severe obesity combines restriction of the stomach with redirection of the small intestine to decrease the amount of food absorbed into circulation. The most common and successful procedure performed in the United States is the Roux-en-Y procedure, which involves the creation of a small pouch from the stomach, which is then attached to the distal portion of the jejunum. This creates a feeling of fullness and reduces the amount of food ingested as the banding procedures. Because a large portion of the small intestine is bypassed, the amount of calories absorbed is greatly reduced.10

In contrast to banding procedures, combined restrictive/malabsorptive procedures have the advantage of patients losing more weight than in banding-only surgery. These procedures also allow patients to more effectively keep the weight off. At ten years or greater after surgery, many patients maintain 60-70 percent of the weight originally lost after surgery.10

Patients undergoing combined procedures are at risk of nutritional deficiencies. Decreased calcium absorption may lead to osteoporosis. Menstruating women may be deficient in Vitamin B12 after the procedure. Patients are prescribed vitamin supplements after surgery. These patients may also experience “dumping syndrome” characterized by nausea, bloating, abdominal pain, and diarrhea after eating meals high in carbohydrates.

Because of the more invasive nature of the combination surgeries, patients undergoing these procedures can experience potential complications of infection and bleeding, but also abdominal hernias (as great as 28 percent), ileus, or death (in less than one percent).

How To Keep It Off
Perhaps the most important aspect of weight management is how to maintain a healthy weight after weight loss occurs. Many patients are successful at weight loss through a variety of means, but only a small portion of these patients keep weight off over time. It has been estimated that only about 20 percent of people who lose at least 10 percent of their initial body weight maintain the loss for at least one year.11 This is a sobering statistic in light of the dangers of obesity in the United States and globally.

As part of the National Weight Control Registry, Dr. Wing and Dr. Hill have followed more than 4,800 patients who have lost at least 13.6 kg (30 lbs) and have kept it off for at least one year. These patients have lost an average of 33 kg and have maintained the minimum weight loss of 13.6 kg for an average of 5.7 years.11 Fifty-five percent of these patients lost weight with the help of either a commercial program or guidance with a nutritionist, while the rest of the patients lost weight entirely on their own. A reported 89 percent of patients used both diet and exercise to lose weight.12
Most pertinent were six factors that all successful patients had in common (see table 5). The patients engaged in a high level of exercise. Men in the study reported expending an average of 3,293 kcal/week and women expended and mean of 2,545 kcal/week. Patients in the study consumed an average of approximately 1,800 kcal/day and ate a consistent diet through the week and through holidays.

These patients also consistently ate breakfast, which usually consisted of some type of cereal and fruit. More than 44 percent of these patients weighed themselves on a daily basis and 31 percent weighed in at least once a week. Finally, patients in this study considered even a slight weight gain as qualifying them as being overweight.11

As part of the registry, Dr. Wing and Dr. Hill also reported factors associated with weight regain. The most powerful predictor of whether a patient maintained weight loss was time, that is, the longer a patient had kept it off, the more likely they were to keep it off. Another predictor was the amount of weight gained. The more weight regained, the less likely the patient was to keep the initial weight lost off.

Psychological Rewards
One other finding from these patients was significant. Weight loss led to improvements in energy levels, physical mobility, mood, self-confidence, and overall physical health.13

Conclusions
Obesity is a significant problem facing physicians today and the illnesses associated with overweight and obese patients are well documented. Data suggest that obesity is increasing in prevalence in the United States and its effects on the population and economy are profound. Intuitively, preventive medicine policy and interventions should be designed to effectively address this epidemic, and by doing so can greatly reduce the morbidity and mortality associated with obesity.

Evidence exists that obesity may have a significant genetic component. Patients should be educated about the dangers of obesity, and its probable genetic components focusing on the benefits that await those who do lose weight and keep weight off (see figure 5).

Not only does weight loss produce increased energy, better mood, and more self confidence, it produces measurable changes in markers for cardiovascular and other diseases. As patients seek advice regarding weight loss, our counsel should focus on these benefits at least as much as the dangers of keeping unhealthy weight.

There are many ways in which patients can lose weight. The method of choice in most cases should be correlated with measures of obesity, such as the body mass index (see table 6). Whatever method of weight loss is chosen, it should be one that will encourage adherence to that program not only throughout the initial period of weight loss, but throughout the patient’s lifetime.

Perhaps the most important principle for patients is how to maintain a healthy weight after they have lost unwanted pounds. Patients successful at keeping weight off seem to follow six habits. These patients eat a low-calorie, low-fat diet, and follow that diet consistently over time. They eat breakfast regularly. They engage in high levels of physical activity and monitor their weight regularly. Finally, these patients catch weight gain before it becomes too great.

Physicians have the opportunity to play a significant role in educating patients on how to successfully lose weight, and keep weight off.

Acknowledgment
The author is grateful for the expertise and contribution of Richard Harvey, PhD.

Dr. Harvey is a graduate of the Arizona College of Osteopathic Medicine and is currentlly a Neurosurgery resident at BroMenn Regional Medical Center in Bloomington, Illinois.

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