What is obesity?

Obesity is an emerging health problem in India and is now recognised as a chronic illness.

Definition of obesity is based on the degree of excess fat. More than a general accumulation, the distribution of fat around the abdomen is now considered to be more harmful than fat around the hips. Accumulation of fat around abdomen indicated by higher waist circumference is considered as a risk factor for various diseases.

In general, BMI ranging from 18.5 to 25 is considered to be normal. However, for Asians it is recommended that the BMI should be between 18.5 and 23, since, they tend to have higher percentage body fat even at lower BMI compared to Caucasians and Europeans, which puts them at higher risk of chronic non-communicable diseases.

Classification of Overweight and Obesity by BMI, Waist Circumference, and Associated Disease Risk.[1]

The underlying cause of obesity is an energy imbalance between calories consumed and calories expended. Multiple factors control food intake and body weight including genetic factors, hormones, sleep deprivation, psychological factors, environmental factors, physical inactivity etc.

Around 60-90% of all people with type 2 diabetes are obese.[2][3]

A strong relationship between obesity and the onset of diabetes has been reported in a number of studies.

Further since in an Indian, the body fat percentage is significantly higher than a western counterpart with similar BMI and blood glucose level. It has been hypothesized that excess body fat and low muscle mass may explain the high prevalence of hyperinsulinemia and the high risk of type-2 diabetes in Asian Indians.[4] The risk of diabetes increases exponentially as BMI increases above about 25[5]

What is Body Mass Index (BMI)?

Body Mass Index (BMI) is a measurement of a person’s weight with respect to his or her height. It is more of an indicator than a direct measurement of a person’s total body fat.

Weight Loss Goals

Weight loss of 5–10% of baseline body weight is recommended as an initial goal of treatment, and this amount of weight loss is associated with a 0.6–1.0% reduction in A1C and numerous other health improvements[6].

However, weight loss of as little as 2–5% also produces a clinically meaningful reduction in fasting blood glucose (20 mg/dL)⁵. The American Diabetes Association (ADA) recommends that patients with prediabetes lose 7% of baseline body weight to avoid developing diabetes[7].

There is no single regimen for weight reduction; it has to be individualized. Weight reduction should be gradual.

Remember the following points to lose weight in a healthy manner:

• Weight reduction diets should not be less than 1000 Kcal/day and provide all nutrients.
• A reduction of half a kilogram body weight per week is considered to be safe.
• Extreme approaches should be avoided and use of drugs may be dangerous.
• In children, obesity should be controlled by increasing physical activity rather than restricting food intake.
• Modifications in dietary habits have to be incorporated into one’s lifestyle along with adequate exercise to keep the body weight within the normal limits.
• As fat contains more than twice the calories (9Kcal) per gram compared to protein (4Kcal) and carbohydrate (4Kcal), weight reducing diets should limit the fat intake.
• Refined sugars (4Kcal) and alcohol (7Kcal) provide empty calories and should be avoided.
• Refined carbohydrates which promote fast absorption of glucose also need to be restricted.
• Plant foods that provide complex carbohydrates and fibre may be preferred as they reduce blood glucose, cholesterol and triglycerides.
• Weight- reducing diets must be rich in proteins and low in carbohydrates and fats.

To lose weight, experts recommend that at least 60 minutes of moderate- to  vigorous-intensity physical activity be taken on most days of the week.

There are two basic levels of physical activity:

Moderate:

This includes walking briskly (about 5-6 KM in an hour), climbing, gardening/yard work, dancing, walking short distances for fetching milk and vegetables, bicycling (about 16 KM in an hour), and weight training (a general light workout), playing with children etc.

Vigorous:

Examples are running/jogging (7 KM in an hour), cycling (> 16 KM in an hour), swimming (freestyle laps), aerobics, brisk walking (6 KM in an hour), weight lifting (vigorous effort), competitive sports and heavy yard work, such as digging, cutting wood.

If a physical activity does not increase the heart rate, it is not intense enough to be counted in the category of “45 minutes of exercise a day”.

Conclusion:

Obesity and diabetes which have become major health problems in India as well as globally are closely linked together. Obesity serves as a major risk factor for type 2 diabetes and weight management can reduce the risk of diabetes to a large extent. Urbanisation, changing life style & food habits are the main reasons for increasing obesity in India and consequently responsible for increasing incidence of diabetes. Increasing physical exercise, eating healthy and maintaining ideal weight can lower the chances of developing diabetes.

References:

[1] 1998 Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults–The Evidence Report. National Institutes of Health. Obes Res 6 Suppl 2:51S-209S

[2] Halpern A, Mancini MC. Diabesity: are weight loss medications effective? Treat Endocrinol. 2005;4:65–74.

[3] Stumvoll M, Goldstein BJ, van Haeften TW. Type 2 diabetes: principles of pathogenesis and therapy. Lancet. 2005;365:1333–1346

[4] Pandya H, Lakhani JD, Patel N. Obesity is becoming synonym for diabetes in rural areas of India also – an alarming Situation. Int J Biol Med Res. 2011;2(2):556–560.

[5] Chan JM, Stampfer MJ, Ribb EB, et al. Obesity, fat distribution and weight gain as risk factors for clinical diabetes in man. Diabetes Care. 1994;17(9):961–969.

[6] American Diabetes Association . Standards of medical care in diabetes—2016: abridged for primary care providers. Clin Diabetes 2016;34:3–21