The National Health Assessment and Nutrition Examination Survey for 2009 through 2010 found that more than 65% of American adults were overweight and more than 35% were obese. Adult aged 60 and over were more likely to be obese than younger adult. Obesity is one of the most important risk factors for osteoarthritis of knees. The association between obesity and OA of hip is not as strong as OA of knees.

Recent studies found that adult who are overweight or obese were significantly more likely to have disc degeneration than those with a normal body mass index (BMI). Elevated BMI is associated with a significant increase in the extent and severity of disc degeneration. Weight gain, physical loading on the disc and/or a chronic low-grade inflammation from the fat cells may play a role in disc degeneration. Overweight and obese also increase the risk of lower back pain. Overweight may cause excessive mechanical stress to all spinal structure including joints, disc, ligaments and muscles, which may aggravate back pain.

Except for osteoarthritis and disc degeneration, overweight and obese have also related to other musculoskeletal problems. Obese people are two time more likely to develop carpal tunnel syndrome than are people of average weight, and women are three times more likely to develop it than are men. The pain, numbness, and tingling of the fingers characteristic of carpal tunnel syndrome are the result of compression of the median nerve. This can result when the carpal tunnel become narrowed or when the tendons become enlarged. In obese people, adipose tissue can compress the median nerve. When obese people arise from a chair, they generally have to move their feet closer under their body and use their arms to push out of a chair. This extends weight-bearing wrists, which may put additional pressure on the median nerve and rotator cuff tendons of the shoulders.

In one study, the risk of rotator cuff tendinitis was 25% higher for overweight patients, 80-120% higher for moderately obese patients, and 300% higher for patients who body mass index (BMI) was 35 or above. The contribution to shoulder problems may due to not only adaptive movements described above but decreased blood flow to the rotator cuff tendons due to atherosclerosis which is common in obsess people. Rotator cuff tendons, lack of adequate blood supply, are vulnerable to trauma.

It may be oversimplification to say that the excess weight caused the problems and that losing weight will solve it. Sometimes, a causative relationship between musculoskeletal problems and excess weight has very difficult to establish. However, weight loss can not only make a substantial difference in most musculoskeletal problems but offer benefit for cardiovascular fitness and other healthy reason.