Obese individuals are more likely to develop type II diabetes, cardiovascular disease, hypertension (high blood pressure), and osteoarthritis 8,9. Other afflictions obese individuals are prone to develop include infertility, birth defects, carpal tunnel syndrome, gallbladder disease, impaired immune system, liver disease, pancreatitis, sleep apnea, and end stage renal disease 9. Also, cancers including colorectal, renal, breast, esophageal, gastric cardia, and endometrial are more likely to occur in the obese population 12 .
Obesity is associated with negative effects on cardiovascular health. For example, research implies that obesity may exhibit a strong effect on lipoprotein metabolism (cholesterol metabolism) 43. Increased weight tends to elevate low-density lipoprotein cholesterol (LDL-C; “bad" cholesterol) and lower high-density lipoprotein cholesterol (HDL-C; “good" cholesterol) 40. Such an occurrence increases the likelihood for developing heart disease 38. This is due to LDL-C accumulation through damaged endothelial layers (the cell layer that lines arteries) and inadequate HDL-C which can transport LDL-C away from the endothelial surface 38. Hypertension, which increases shear stress on vessels, is associated with obesity 3. Increased shear stress augments vascular wall injury providing greater area for LDL-C to accumulate and possibly form plaques in arteries 38 . Adiposity level is a predominant factor underlying increased coronary risk among men. Excess body weight plays a dominant role in predicted coronary heart disease risk 53.
Many individuals have difficulty performing daily activities because of pain. There is a strong association between the amount of pain-related activity-difficulty and impaired health-related quality of life. Specifically, the more difficulty there is performing activities because of pain, the lower the health-related quality of life. Obesity and smoking are two factors that are strongly associated with an increase in the number of days an individual experiences difficulty performing activities because of pain 72.
A variant of the MC4R gene is associated with physical activity levels of an individual. This gene variant may contribute to the tendency of some individuals to be more sedentary than others 50.
Obesity is listed as a component of the metabolic syndrome 27,29. In literature originating from the 1980’s, obesity is also referred to as syndrome X. Metabolic syndrome involves hypertension, dyslipidemia (abnormal cholesterol profile), obesity, and insulin resistance 26,27,29. Insulin resistance may be the result of the latter three components and can eventually lead to insulin dependent type II diabetes 26 . Recent studies identify six components of the metabolic syndrome that relate to cardiovascular disease 26 . These include abdominal obesity, atherogenic dyslipidemia (dyslipidemia that contributes to plaque formation in arteries) , raised blood pressure, proinflammatory state, prothrombotic (pro-clot formation) state, and insulin resistance with or without glucose intolerance 26. Abdominal obesity is noted because it is the type of obesity that is associated most frequently with metabolic syndrome 23,29. Children who were large for their gestational age and were birthed from mothers with maternal obesity are at two times the risk of developing metabolic syndrome 7.