Types of Body Fat

The human body possesses two distinct types of body fat, referred to as brown and white. Both forms of body fat are active, living parts of us, heavily influencing our metabolism, protecting our organs, glands and bones, and offering many other health benefits mostly from our stores of white fat. This body fat content ranges from five percent in some male athletes to more than 50 percent of total body weight in obese individuals. Brown fat makes up only about 1 percent of the total body fat in healthy adults, although it’s much more abundant at birth in healthy babies.

Brown fat helps us burn white fat; this is an important aspect of overall health. (Even in athletes, it’s an important energy source for better performance.) Without adequate brown fat, we can gain body fat and become sluggish in the winter like a hibernating animal.

There are a number of ways to increase brown fat activity.

Certain foods can stimulate brown fat and increase overall fat-burning. Eating several times a day, five to six smaller healthy meals instead of one, two or three larger ones, for example, can trigger a process called thermogenesis — an important post-meal metabolic stimulation for fat-burning. However, if caloric intake is too low, brown fat can slow the burning of white fat. This can happen on a low-calorie diet and when we skip meals.

Brown fat is also stimulated by certain dietary fats. The best ones are omega-3 fats, especially from fish oil, and olive oil (use olive to replace all vegetable oils in the diet). This works in part because a moderately high healthy-fat diet can stimulate brown fat.

Other foods that increase brown fat activity include caffeine. Tea, coffee and chocolate contain small to high amounts of caffeine.

However, if under stress, the adrenal glands become overworked, which can promote fat storage and reduce fat-burning; caffeine may worsen adrenal stress in many individuals. Also, avoid coffee, tea and chocolate products if they contain sugar, which can reduce fat-burning.

While supplements of fish oil may be the only way to obtain adequate amounts of EPA, some supplements can be harmful. A popular supplement, CLA (conjugated linoleic acid), can actually reduce brown fat activity.

Brown fat is greatly controlled by skin temperature. If you get too hot during the day, or overdress during exercise, brown-fat activity can lead to less burning of white fat. This is why exercising in extra clothes or “sweatsuits,” a common but unhealthy weight-loss routine, can be dangerous.

Even sitting in a hot tub, sauna or steam room regularly after exercise may offset some of the fat-burning benefits of physical activity. These activities can increase sweating, resulting in some water- weight loss, but the sacrifice is actually less fat-burning. Hot tubs and saunas do come with health benefits, but to avoid the reductions in fat-burning take a minute or two to cool the body in a cold shower or tub afterwards.

In contrast, brown fat is stimulated by cold. Cooling the body’s brown-fat areas can help stimulate more fat-burning. Brown fat is found around the shoulders and underarms, between the ribs and at

the nape of the neck. These are important areas to keep from over-heating and cool after exercise. (Low body temperature is associated with reduced fat-burning; this is often related to low thyroid function.)

Of course, exercise can increase fat-burning too. The best kind being the easy aerobic type, such as walking, which trains the body to burn more body fat all day and night. This issue is discussed in detail in later chapters.

Unfortunately, most research in the area of brown fat comes from the pharmaceutical industry, which is looking for a new drug to stimulate brown fat. But a healthy diet, the right exercise and other lifestyle habits already can do this!

The role of brown fat is just another of the many examples of healthy functions of fat in the body. But to make sure we have healthy, balanced fats, we must be very careful with the types and amounts of fats we consume.

It’s time to look at fat as our friend. Good fats can greatly help in the quest to improve optimal health and human performance.