Weight Gain and obesity have long been linked to a sedentary lifestyle. Also there has been a consensus relating all cause weight gain to excess calories intake. Considerable and extensive research suggests that weight loss mechanisms of diet control often almost relates to the belief of the person in the diet that helps him or her to follow the diet strictly to gain on weight loss regime.
It is important that before one sets self goals for weight management, one must get evaluated or consider the risk involved with overweight existence and hazards associated with it.
Overweight refers to a weight above the “normal” range. This is determined by calculating the body mass index (BMI, defined as the weight in kilograms divided by height in meters squared). Overweight is defined as a BMI of 25 to 29.9 kg/m2, obesity as a BMI of >30 kg/m2. Severe obesity is defined as a BMI >40 kg/m2 (or ≥35 kg/m2 in the presence of comorbidities).
Obesity and increased central fat are associated with increased morbidity in addition to mortality. verweight and obese individuals had a higher relative risk of:
• Diabetes mellitus
• Insulin resistance
• Heart disease
– Coronary disease
– Heart failure
– Myocardial steatosis
– ECG in morbid obesity
– Atrial fibrillation/flutter
• Venous thrombosis
• Hepatobiliary disease
• GERD/GI cancer
• Skin changes
• Respiratory system
• Endocrine changes
• Kidney disease
• Kidney stones
• Urinary incontinence
• Psychosocial function
Meta Analysis of extensive research, suggest choosing a diet or eating plan based upon patient preferences, which may improve long-term adherence.
Conventional diets are defined as those with energy requirements above 800 kcal/day.These diets fall into the following groups:
●Balanced low-calorie diets/portion-controlled diets
Fad diets (diets involving unusual combinations of foods or eating sequences) are extremely popular but only for a short period of time. Most fad diets are not sustainable in the long-term.
tailoring a diet that reduces energy intake below energy expenditure to individual patient preferences, rather than focusing on the macronutrient composition of the diet .
Behavior modification strategies are important to improve dietary compliance with any type of diet.
●If a low-carbohydrate diet is chosen, healthy choices for fat (mono and polyunsaturated) and protein (fish, nuts, legumes, and poultry) should be encouraged. If a low-fat diet is chosen, the decrease in fat should be accompanied by increases in healthy carbohydrates (fruits, vegetables, whole grains).
Side effects — Very-low-carbohydrate diets may be associated with more frequent side effects than low-fat diets. In one of the trials noted above, a number of symptoms occurred significantly more frequently in the low-carbohydrate compared with the low-fat diet group.
Although many individuals have success losing weight with diet, most subsequently regain much or all of the lost weight. Maintaining weight loss is made difficult by the reduction in energy expenditure that is induced by weight loss.
There is little consensus on the optimal mix of macronutrients to maintain weight loss. The satiating effects of high-protein, low-glycemic index diets have generated interest in manipulating protein composition and glycemic index in weight maintenance diets.
Prolonged caloric restriction improved longevity in rodents and non-human primates, but the impact of calorie restriction on longevity in humans is unknown.
It is hypothesized that the antiaging effects of caloric restriction are due to reduced energy expenditure resulting in a reduction in production of reactive oxygen species (and therefore a reduction in oxidative damage). In addition, other metabolic effects associated with caloric restriction, such as improved insulin sensitivity, might also have an antiaging effect.
In one trial of 48 sedentary, overweight men and women, six months of caloric restriction, with or without exercise, resulted in significant weight loss as expected.
In addition, calorie restriction-mediated reductions in fasting insulin concentrations, core body temperature, serum T3 levels, and oxidative damage to DNA (as reflected by a reduction in DNA fragmentation) were seen, suggesting a possible antiaging effect of the prolonged caloric restriction.