The optimal maintenance of one’s weight, especially if you are overweight or obese by your BMI, patients requires a combination of diet, exercise and behavioral modification. In addition, some patients eventually require medication or surgery. Whether you ever achieve your weight health goals if you are overweight or obese a loss of 5-7% of body weight carries numerous health benefits and should be sought as an initial weight loss goal. Weight loss of more than 5% can reduce risk factors for cardiovascular disease, such as high cholesterol, high blood pressure, arthritis, joint disease, cancers, gall bladder disease, fatigue, and diabetes.
On any diet plan your rate of weight loss is directly related to the difference between an individual’s energy intake and energy expenditure. Reducing caloric intake below expenditure should result in a predictable initial rate of weight loss that is related to the deficit. However, prediction of weight loss for an individual can be difficult because there is a range of weight loss that varies between individuals and diets. Factors that predict response to a diet include dietary adherence, medication, and genetic factors influencing body composition and energy expenditure.
The more lean body mass (muscle) you have, the higher your energy expenditure (calories burned) is. Metabolic rate (metabolism) declines by approximately 2% per decade. There are several ways of formally estimating energy expenditure including body composition testing and the WHO criteria, and we can help you test, but simple criteria are by calculation. Women 31-60 years = (0.0342 x weight in kg + 3.5377) x 240kcal/day x activity factor (1.3-1.7) = total energy expenditure. For example, a 35 year old women whom weighs 180# or 81.8kg whom is largely sedentary would require 1,976 kcals/day to maintain her weight.
Keeping a food journal for a few days to count your baseline calories, An average deficit of 500kcal/day should result in an initial weight loss of approximately 1 pound per week. After a period of weight loss, energy expenditures should be recalculated to avoid plateaus and allow for continued weight loss.
General recommendations for a healthy diet including elimination of all caloric beverages and processed foods. Focus on portion control. Self-monitor food intake by journaling. Adopt a healthy, life-long approach to eating. Identify behavioral triggers that cause poor food choices or overeating. There is possibility that highly processed foods, nonnutritive sweeteners and other artificial additives may impact body weight beyond the calories they contain, by directly or indirectly changing the gut microbiome. This is an area of continued research. We do encourage all of our medically supervised dieters to actually pick a type of diet to increase weight loss.
Types of diets:
- Balanced low-calorie diets and low-calorie versions of healthy diets such as DASH or Mediterranean Diet. Planning this diet means selecting a caloric amount and then choosing foods to meet this intake. It is desirable to eat foods with adequate nutrients in addition to protein, carbohydrates and essential fatty acids. The term Mediterranean diet refers to a dietary pattern that is common in olive-growing areas of the Mediterranean. They include a high level of monosaturated fat relative to saturated fat; moderate consumption of alcohol, mainly as wine; a high consumption of vegetables, fruits, legumes and grains; a moderate consumption of milk and dairy; and a relatively low intake of meat and meat products. It appears to be associated with several health benefits including cardiovascular disease and diabetes prevention. The DASH diet is comprised of 4-5 servings of fruit, 4-5 servings of vegetables and 2-3 servings of low fat dairy per day and less than 25% of intake from fat. This diet can lower blood pressure.
- Sirtfood diets. Focus on foots that will activate your sirtuin genes. Foods such as apples, citrus fruits, parsley, capers, blueberries, green tea, soy, strawberries, turmeric, olive oil, red onion, and kale are the focus of the diet. It would be similar to eating Mediterranean type diet and can have some chicken and fish. The focus is more on anti-aging and healthy eating than weight loss.
- Low-fat diets are another standard strategy to help patients lose weight. A low fat dietary pattern with healthy carbohydrates (fruits, vegetables, whole grains) is not associated with weight gain. Many experts recommend keeping calories from fat below 30% of total calories.
- Low-carbohydrate diets similarly to the low fat diets focus on your carbohydrate intake. If a low carbohydrate plan is chosen, healthy choices for fat (mono or polyunsaturated) and protein (fish, nuts, legumes, poultry) should be encouraged because of the association between saturated fat intake and cardiovascular disease. Restriction of carbohydrates leads to glycogen mobilization and if carbohydrate intake is less than 50g/day, ketosis will develop. Rapid weight loss occurs, primarily due to glycogen breakdown and fluid loss, rather than fat loss. In addition, very-low carbohydrate, ketogenic diets are associated with a small increase in energy expenditure that wanes over time. Low-carb diets with healthy choices for fat and protein may have beneficial effects on diabetes prevention, cardiovascular disease and some cancers. Very low carb diets may be associated with more frequent side effects than low-fat diets including constipation, headache, halitosis, muscle cramps, diarrhea, weakness and rash.
- High-protein diets have been recommended for the treatment of obesity because they are more satiating and stimulate thermogenesis and may improve weight maintenance.
- Ketogenic Diets
- Very low calorie diets are diets with energy levels between 200 and 800kcal/day. The basis for these diets was the notion that the lower the energy intake, the more rapid the weight loss. They have not been shown superior to conventional diets for long term weight loss. Side effects of this diet include hair loss, thinning of skin, coldness. There is also an increased risk of gallstones. Generally exercise restriction is recommended with these diets. These diets should be reserved for individuals who require rapid weight loss for a specific purpose, such as surgery. Close monitoring is advised. The weight regain when the diet is stopped is often rapid.
- Alternate day fasting has been proposed as a strategy to produce weight loss. This approach alternates fasting days (25% of energy needs) with feeding days (125% of energy needs). The weight loss with this approach is similar to a diet of overall caloric restriction (75% energy every day) but may be easier for some patients to follow.
The general consensus is that excess intake of calories from any source, associated with a sedentary lifestyle, causes weight gain and obesity. The goal of dietary therapy, therefore, is to reduce the total number of calories consumed. Diets which emphasize reductions in refined carbohydrates, processed meats, and foods high in sodium and trans fat; moderation in red meats, poultry, eggs and milk; and high intake of fruits, nuts, fish, vegetables, vegetable oils, minimally processed whole grains, legumes and yogurt are preferred. A principal determinant of weight loss appears to be the degree of adherence to the diet, irrespective of the particular macronutrient composition. It is important that patients select a diet that they will be able to adhere to. The optimal mix of macronutrients for long term weight loss or weight maintenance is unclear. In addition to a patient-selected diet, behavioral modifications are also helpful to improve compliance and may have the greatest impact on long-term weight loss.