Can't Lose Weight? Blame A Caveman

One of the oddities of growing older, if you happen to have the genes for it, is the phenomenon of ectopic fat deposits. Ectopic fat deposits can make you a literal fathead. But we mean that only in the nicest possible way.

Ectopic Fat Deposits, an Inheritance from the Neanderthals

In some people's bodies, fat doesn't just accumulate on the hips, around the waist, or thundering on the thighs. About the age of 40, some people start accumulating fat deposits between their vital organs, forming what is known as an omentum, and even in their vital organs, such as the heart, liver, and brain. 

In 2010, scientists recovered a 50,000 year-old toe bone from a dig in the Ural Mountains on the western edge of Siberia. Tens of thousands of years in a natural deep freeze had preserved the DNA in the toe bone, giving researchers their first opportunity to analyze the complete sequence of Neanderthal DNA. Neanderthals, an ancient relative of modern human beings, went extinct about 30,000 years ago, but not before intermarriage with the ancestors of modern human beings.

These matings between Neanderthals and humans occurred in the ancient Middle East after the ancestors of today's Africans and Asians had migrated to other parts of the globe, so it is primarily people of European ancestry, rather than Asian, African, Native American, or Native Australian ancestry, who carry Neanderthal genes. Most contemporary people of European descent have between 1 and 4% Neanderthal DNA.

Differences in Fat Metabolism, Too

Modern people who carry the Neanderthal genes are prone to accumulation of fat in odd places. It can grow inside bones. It can grow inside the heart and the liver. And it can grow inside the brain.

Because fat cells generate inflammatory compounds, these misplaced fatty tissues can wreak havoc in the tissues in which they grow. When these fat cells finally "get the message" that they are in the wrong tissue and self-destruct, the chemicals that destroy them can also destroy healthy cells of the tissues around them. 

And unlike the soft, jiggly fat that can accumulate directly below the skin, the visceral fat called the omentum can "strangle" vital organs and hasten the diseases of aging. But could there possibly be anything good about the biology that turns you into a literal fathead?

See Also: Suprising Problem Foods For The Paleo Diet

Perfectly Adapted to a Severe, Cold Climate

What the Neanderthals had going for them that they passed on to their offspring with humans was a superb ability to withstand the cold and starvation. All those fat cells provided the tissues around them with ready energy when food was in short supply. Brown fat cells even acted as little heaters to keep the body warm. People who have European genetics still tend to stand up better to extreme cold, and certain metabolic conditions that are more common among people of European descent, such as diabetes, high cholesterol, and high blood pressure, are not as severe during cold weather.

Making Your Neanderthal Genes Work for You When You Lose Weight

So, for better or for worse, if you are stuck with some ancient Neanderthal's genes for fat storage, how can you make them work for you to help you lose weight? The secret may be working with your genes rather than against them.

Brown Fat, White Fat, Working Fat, Storage Fat

Your body has two kinds of fat cells, white fat cells and brown fat cells. White fat cells primarily store fat. Brown fat cells primarily burn it. Your brown fat cells are activated by a signal from your vagus nerve when you experience cold. Without the signal from the vagus nerve, they don't kick into overdrive burning fat to keep you warm. Your vagus nerve has to be intact and functional to send the right signals for burning fat.

Brown fat is activated by your sympathetic nervous system, the part of your nervous system that powers your fight or flight responses, your conscious, intentional muscle movements. Your brown fat burns more calories when you are alert, awake, and calmly in control.

Cold to Trigger Fat Burning

How cold do you have to get to trigger fat burning? A series of clinical experiments have found that cold exposure just short of the level that causes shivering is needed to activate brown fat. This can be accomplished by cooling the skin without lowering room temperature; many of the experiments measuring fat burning in volunteers exposed to cold used chilled mattresses but kept room temperature relatively warm, 25 degrees C/77 degrees F. 

Exposure to the cold needs to be nearly constant. Just a few hours of warmth stops extra burning of calories by brown fat. But constant exposure to cold raises the basal metabolic rate and burns fat.

How Much Difference Does Cold Make in Losing Weight?

How much fat? One study found that applying enough cold to lower the temperature of the skin (not the body core!) 6 degrees C/10 degrees F increased basal metabolic rate by 7 joules per second. In terms of "calories," that's about 150 to 200 calories per day for most people. 

See Also: The Truth About Paleo Diets

For even faster results, become a polar bear, and make a habit of swimming in cold water. Or just splashing around in cold water. If you keep on swimming outdoors even as the weather changes, you almost certainly will lose weight easily. The author of this article once managed to lose 25 pounds over winter by continuing to swim outdoors all winter long in northern California.

Cold exposure will help you lose weight even if you don't have Neanderthal ancestors. It will help you lose weight even more quickly if you do.