Beta-III & Me

Dear DOCTOR Owen:

I am three-quarters Native American and overweight. Most of my family is also overweight. In fact, my entire tribe is overweight. We had a recent tribal gathering, which looked like a convention of Sumo wrestlers. I have heard that Native Americans have a higher incidence of obesity. Is that true and why?

Poca Out

Dear “Poca”:

You are correct about the incidence of obesity in Native Americans—especially those who live in the United States. If you live in the southwestern United States, your cousins down in Mexico are much less likely to be obese, which suggests that both genetics and environment are playing a role in your obesity.

Pima Indians are now the prototypical obesity study population on the planet. This is because Pima Indians living in the mountains of Mexico, away from civilization, are thin. Their first cousins who live in cities, however, are universally obese. Immediate family members who live in the United States, right across the border, are even fatter. (Cola consumption was found to be the greatest variable for the U.S. obesity.) Because Pima members do not usually breed outside of their tribe, they offer a good “lab” of obesity research. Is obesity due to the environment or genetics? The answer is both!

It has been shown that Pima Indians, and perhaps many Native Americans as well, have a calm nervous system. They seem to make less adrenaline-like chemicals in their nervous systems. For example, when people get an “adrenaline” rush, they become nervous and take action—fight or flight! A part of the nerve cell that attaches, or “captures,” the adrenaline is called the “Beta receptor.” Once “captured,” the adrenaline excites the nerve fiber and causes action. If on a muscle, the Beta-receptor nerve causes a “fidget” or a firing of the muscle and burns a tiny amount of energy.

While there are at least four types of Beta receptors, Type III has been shown to cause fat to readily burn in animals. The brain, through the Beta-III system, controls hibernation—fat and seasonal fat stores in animals. When activated, Beta-III receptors break down fat, even if calorie deprivation is not present. As you might guess, there is much research interest in Beta-III stimulation. If present in humans, this could be an excellent way to stimulate metabolism without extra dieting.

Researchers at the University of Buckingham, England, reporting in the International Journal of Obesity, Vol. 23, 10, 1057–1066, found a new method to detect Beta-III receptors. So far, Beta-III appears to be present in muscle, the heart, and intra-abdominal fat deposits. And, it may be present throughout the body. This is important because low levels of Beta-III could cause increased risk of obesity, diabetes, and even the impaired metabolism of certain drugs. Increased alcoholism in Native Americans could even be related to findings such as this.

Asthma medications, caffeine, and the dietary stimulant Ma Haung (ephedrine, as in pseudoephedrine) stimulate the Beta receptors and make people feel as if they are experiencing an adrenaline surge. Most of us have experienced surges of adrenalin, which make us jittery and nervous, and may cause cardiac rhythm disturbances. However, they do not seem to stimulate the Beta-III receptor very much. If such an agent is found and proven to be safe and useful, it may play a role in weight—and even diabetes—management. Most over-the-counter diet supplements contain caffeine and Ma Haung and are, therefore, harmful.

A Beta-III agent has been invented, and studies of its effect on humans will soon begin. In fact, my clinic is being considered as a study site for this agent. It may be 10 years before a drug such as this could make it to market, but for the young and for those struggling with familial obesity, it could be a future player. Of course, if it causes any complications, the company will not have enough money to fend off the lawyers and bankruptcy. So, it will be slow in coming, expensive, and available everywhere else on the planet first (please forgive the editorializing here).

In the meantime, you may be able to stimulate Beta-III receptors every day: by exercise.