Obesity Overview 

• Obesity is a major modifiable risk factor for cardiovascular disease (CVD) and its adverse effects are largely mediated by dyslipidemia, high blood pressure, and even non-alcoholic fatty liver.¹  In fact, the elevated CVD risk associated with obesity and abdominal obesity disappears when information from total cholesterol, HDL, blood pressure and diabetes are included.²

• Obesity levels have risen sharply and have become a major global health problem. Even in those countries that historically had lower rates of obesity, there is now evidence of increasing overweight. Many developing countries like India face the challenges of under nutrition while confronting obesity at the same time.

• There are 400 million adults worldwide who are obese and 1.6 billion who are overweight. These numbers are expected to reach 2.3 billion and 700 million, respectively, by 2015.

• Obesity is primarily due to overeating in relation to physical activity. Globally humanity is becoming more physically inactive.³ Diets have moved from being plant-based to high-fat, energy-dense animal-based diets.

• Obesity is a risk factor for cancer, hypertension, dyslipidemia, diabetes and obstructive sleep apnea and is associated with CVD.^{4, 5} Obesity is the major contributor to the insulin resistance and metabolic syndrome, a condition of multiple metabolic abnormalities that is a precursor to diabetes, and confers a high risk for CVD events.

• The incidence of diabetes is 3-fold in men and 5-fold in women with obesity and even higher with abdominal obesity. The risk of developing diabetes in 20 years is increased by a factor of 15 in people with obesity and 30-fold in those with obesity and metabolic syndrome according to a Swedish study.⁶

• Obesity has become the most prevalent cause of preventable death in US surpassing tobacco. Obesity is strong predictor of shortened lifespan (3 years) and earlier onset of CVD and premature deaths (4-12 years).^{7, 8}

• Obese persons spend nearly four times more on medications than people and spend twice the number of days in the hospital or nursing home than normal weight people. A recent Canadian study  has  demonstrated that obesity appears to be an independent risk factor for the failure to attain the blood pressure and lipid targets.⁹

• Body mass index (BMI, a ratio of the weight to height), has long been the standard criteria for obesity, BMI is equivalent to weight in pounds divided by height in inches squared and multiplied by 703 or  as weight in kilograms divided by height in meters squared (kg/m2). Those with BMI >40 are considered extremely obese.

• BMI does not distinguish between fat and fat-free mass nor does it measure the amount or distribution of body fat.

•  Several studies have shown that BMI systematically underestimates the percent body fat and CVD risk among Asian Indians and all Asians.^10-15 As a result, the WHO (Western Pacific Region) has recommended new criteria to classify overweight, obesity and abdominal obesity in Asian Indians that are different from Europids. (Table 005).

• The BMI failed to distinguish the various types of fat depots as well as lean body mass. Percent body fat (% BF) measures total body fatness, which is composed of central and peripheral fat, estimated by waist circumference (WC) and skin fold thickness, respectively.

• Abdominal obesity measured as waist circumference is a better measure of adiposity and the better predictor of the cardiometabolic risk associated with adiposity in Indians and Europids.¹⁶ 

Sources

1. Targher G, Day CP, Bonora E. Risk of cardiovascular disease in patients with nonalcoholic fatty liver disease. N Engl J Med. Sep 30 2010;363(14):1341-1350.

2. Wormser D, Kaptoge S, Di Angelantonio E, et al. Separate and combined associations of body-mass index and abdominal adiposity with cardiovascular disease: collaborative analysis of 58 prospective studies. Lancet. Mar 26 2011;377(9771):1085-1095.

3. St-Onge MP, Keller KL, Heymsfield SB. Changes in childhood food consumption patterns: a cause for concern in light of increasing body weights. Am J Clin Nutr. Dec 2003;78(6):1068-1073.

4. George CF, Kab V, Kab P, Villa JJ, Levy AM. Sleep and breathing in professional football players. Sleep Med. Jul 2003;4(4):317-325.

5. Hurst RT. B, R. F., Wissner E, Roberts A, et al. Incidence of subclinical atherosclerosis as a marker of cardiovascular risk in retired professional football players. Am J Cardiol. Apr 15 2010;105(8):1107-1111.

6. Arnlov J, Ingelsson E, Sundstrom J, Lind L. Impact of body mass index and the metabolic syndrome on the risk of cardiovascular disease and death in middle-aged men. Circulation. Jan 19 2010;121(2):230-236.

7. Peeters A, Barendregt JJ, Willekens F, Mackenbach JP, Al Mamun A, Bonneux L. Obesity in adulthood and its consequences for life expectancy: a life- table analysis. Annals of internal medicine. 2003;138(1):24-32.

8. Madala MC, Franklin BA, Chen AY, et al. Obesity and age of first non-ST-segment elevation myocardial infarction. J Am Coll Cardiol. Sep 16 2008;52(12):979-985.

9. Bhan V, Yan RT, Leiter LA, et al. Relation between obesity and the attainment of optimal blood pressure and lipid targets in high vascular risk outpatients. Am J Cardiol. Nov 1 2010;106(9):1270-1276.

10. Misra A., Khurana L. Obesity-related non-communicable diseases: South Asians vs White Caucasians. International journal of obesity (2005). Jul 20 2010.

11. Dudeja V, Misra A, Pandey RM, Devina G, Kumar G, Vikram NK. BMI does not accurately predict overweight in Asian Indians in northern India. The British journal of nutrition. 2001;86(1):105-112.

12. Jackson A. S., Ellis KJ, McFarlin BK, Sailors MH, Bray MS. Body mass index bias in defining obesity of diverse young adults: the Training Intervention and Genetics of Exercise Response (TIGER) study. The British journal of nutrition. Oct 2009;102(7):1084-1090.

13. Deurenberg-Yap M, Schmidt G, van Staveren WA, Deurenberg P. The paradox of low body mass index and high body fat percentage among Chinese, Malays and Indians in Singapore. Int J Obes Relat Metab Disord. 2000;24(8):1011-1017.

14.  Wang J, Thornton JC, Russell M, Burastero S, Heymsfield S, Pierson RN, Jr. Asians have lower body mass index (BMI) but higher percent body fat than do whites: comparisons of anthropometric measurements. Am J Clin Nutr. Jul 1994;60(1):23-28.

15. Deurenberg-Yap M, Chew SK, Deurenberg P. Elevated body fat percentage and cardiovascular risks at low body mass index levels among Singaporean Chinese, Malays and Indians. Obes Rev. Aug 2002;3(3):209-215.

16. Valsamakis G, Chetty R, Anwar A, Banerjee AK, Barnett A, Kumar S. Association of simple anthropometric measures of obesity with visceral fat and the metabolic syndrome in male Caucasian and Indo-Asian subjects. Diabet Med. Dec 2004;21(12):1339-1345.