I heard they are now saying fat comes in white and brown and the white kind is what leads to joint arthritis. Is this really true?

It is true that scientists have made some remarkable discoveries about fat in the last 10 years. Brown adipose tissue (BAT) (or “brown fat”) and white adipose tissue (WAT) or “white fat” are real phenomenon in the body.

Brown fat is found in larger amounts in new born babies and hibernating mammals. Its main purpose is to generate body heat in animals or newborns because they do not shiver. The brown color comes from a higher number of mitochondria that contain iron.

White fat cells are found in abundance in obese adults. It serves as a storage unit for energy but has also been discovered to be a powerful endocrine gland (producing hormones). These hormones are proinflammatory causing a low-grade inflammation throughout the body (not just the joints). This proinflammatory state of the obese body is also suspected as a contributing cause of hypertension, insulin resistance, and high cholesterol levels.

As a result of these discoveries and this new knowlege, joint osteoarthritis is no longer considered just a “wear-and-tear” type of arthritis. Obesity and the excess weight and load associated with obesity are major factors. But now we know there are inflammatory effects of adipose (fat) tissue that also contribute to joint destruction. Weight loss and exercise aren’t always easy solutions but they are the most successful in addressing all of the local and systemic effects of obesity.