This paper reviews insulin resistance and obesity in humans. Excessive adipose tissue is a risk factor of cardiovascular disease, diabetes mellitus (type 2) and hypertension. More than 50% of the U.S. population is overweight (Body mass index > 25). Around 20% is obese (BMI > 30). Insulin resistance is a predictor of those 3 syndromes, and it is reduced with weight loss. The authors, after several studies over several years, propose a more effective clinical approach to the overweight/obese human patients.