By any standard, the sumo wrestler would be considered obese. Sumo wrestlers weigh in the range of three hundred to four hundred pounds and ingest 5000 to 7000 calories a day, including a lot of fried food. While their diet is low in processed foods and sugar no one could argue that their diet is healthy.

And yet they don’t suffer from afflictions normally associated with obesity. Their plasma glucose and triglyceride levels are normal. Even their cholesterol levels are low. How is it that they can escape the health effects of excess weight in ways the rest of us can’t?

Sumo’s strict exercise regimes may set them apart.

The question puzzled doctors for years, until a study using computer tomography imaging looked at the fat deposits on sumo wrestlers. The study revealed that although the wrestlers have enormous bellies, most of their abdominal fat is stored immediately under the skin, and not behind the stomach wall within the gut or visceral area. In fact, sumo wrestlers had about half of the visceral fat of regular people with visceral obesity.

This fat distribution is crucial to understanding body fat and health. While sumo wrestlers are not what comes to mind when we think of fit athletes, their training routines are quite intense. In fact, sumo wrestlers are only protected from health risks so long as they continue their intense training. When sumo wrestlers retire and veer away from their exercise program, they almost immediately develop more visceral fat and the classic problems of obesity such as high levels of insulin, insulin resistance, and diabetes.

Evidently, the sumo’s physical exercise and diet low in sugar helps him to avoid visceral fat. So how can strenuous activity prevent sumo wrestlers from getting obesity-related ailments?

Exercise has been shown to increase adiponectin levels. This hormone sensitizes the body’s response to insulin, and guides glucose and fat molecules out of our bloodstream and into body fat, where they belong. This is important because an excess of circulating glucose and fats in the blood are precursors for diabetes and metabolic disease. It also removes from circulation toxic lipids known as ceramides, which contribute to insulin resistance, inflammation, and cell death!

The sumo’s intense physical regimen (and the release of adiponectin) enables fat to be stored in the periphery instead of in the visceral area. And when the sumo curtails this exercise regimen, unhealthy visceral fat quickly accumulates.

The tale of the sumo wrestler is just one of many that I write about in The Secret Life of Fat showing the complex interactions that occur in our bodies which are rarely covered in one-size-fits-all diet books. Whether you’re looking to lose weight or learn more about one of the bodies most mysterious organs, follow along as I expose fat!