Cardiovascular system

Increased risk of sudden death, Cardiac Arrhythmias, increased risk of atherosclerosis, abnormal lipid profile with decreased levels of HDL, and increased levels of low density lipoproteins. Prevalence of hypertension is also increased.
A waist circumference above 100 cm in men and above 90 cm in women is associated with increased levels of triglyceride and reduced levels of HDL cholesterol.

Diabetes Mellitus

Type 2 diabetes mellitus [non-insulin- dependent diabetes mellitus] has direct relation with abnormal weight of an individual. Diabetes is almost nonexistent in individuals with a BMI below 22.

Cancer

Obese men – higher incidence of cancer of prostate, colon and rectum.
Obese women – higher incidence of Uterus, Overies and Gal Bladder cancers.

24% of all cancers are linked to obesity

Gall Bladder Disease

Gall Bladder disease with formation of cholesterol stones also increases with obesity.

Respiratory system

Sleep apnoea occurs with excessive obesity.

Joints

Ostheoarthritis and gout is associated with obesity.

Skin Problems

Acanthosis nigricans, manifested by darkening of the skinfolds on the neck, elbows, and dorsal interphalangeal spaces. Fungal and other skin infections in the skin folds.

Endocrine system

Insulin resistance leading to hyperinsulinemia is a uniform feature and is directly related to the degree of obesity. Testosterone levels may be reduced in extreme obesity in men. Obesity leads to an earlier onset of menarche, and greater frequency of irregular and anovulatory cycles, and to earlier menopause.