The fat hormone

If you’re one of many people currently eating a healthy diet, getting plenty of exercise and physical activity but finding yourself unable to shift body fat, a hormone may be the culprit. To understand how a hormone could make you fat, even on a very low-calorie diet, you first need to understand that your fat cells are not simply an inert garbage can that your body stuffs excess calories into.

Fat is a functioning organ just like your liver, kidneys and brain. It is the job of hormones to direct the function of these organs. What if a powerful hormone kept telling your fat cells to simply gobble up more than their fair share of calories from every meal you eat, in the same way that a tumour robs healthy cells of nutrients. Remember that calories are energy, so this would leave less energy for your brain and other organs. You are literally losing energy to your fat tissue.

A brain deprived of energy would make you feel tired and lethargic, so you wouldn’t move around too much and use up precious energy that was needed to keep your body functioning. An energy-starved brain is also a hungry brain that produces chemicals and hormones that quite literally give you the perpetual munchies. You feel hungry and unsatisfied all the time as your brain demands you feed it more energy. If you manage to get yourself off the couch and into the gym using sheer willpower, you’ll find that you feel even hungrier. That old adage about working up an appetite with exercise is quite true.

Getting fatter while starving

Calorie-restriction diets used to be called semi starvation diets until this term fell out of favour in the late 70s for obvious reasons. Yet many people willingly half starve themselves and still can’t shift that stubborn belly fat or, even worse, continue to get fatter. The phenomenon of getting fat while eating very little is not a modern one or even limited to Western developed countries where food is abundant. Researchers have noted the conundrum of malnutrition and obesity existing side by side since the early 1900s.

The following statement by Benjamin Cabellero, director of the Centre of Human Nutrition, John Hopkins University and published in a 2005 edition of the prestigious New England Journal of Medicine challenges our paradigm that obesity is simply due to gluttonous overeating: “A few years ago, I was visiting a primary care clinic in the slums of Sao Paulo (Brazil). The waiting room was full of mothers with thin, stunted young children, exhibiting the typical signs of chronic under-nutrition. Their appearance, sadly, would surprise few who visit poor urban areas in the developing world. What might come as a surprise is that many of the mothers holding those undernourished infants were themselves overweight.” Either these mothers were willing to starve their children so they could get fat or something other than simple overeating can make us fat and keep us fat.

Hormones control everything

Researcher, writer for the New York Times and author of Good Calories, Bad Calories, Gary Taubes, believes we need to change our thinking about what makes us fat. Instead of telling people that the reason they’re fat is because they’re overeating, we need to ask what it is that’s making someone overeat. If a three-metre-tall man walked into a doctor’s office, the doctors first thought would not be, “Oh he’s just tall because he eats too much.” He’d be thinking about what tests he needed to run to identify the hormone imbalance that made his body grow taller than normal. Yet for anyone to grow to the impressive height of three metres they’re going to have to eat an awful lot of food to provide the fuel and building materials for their body to keep growing. Imagine the hungriest teenage boy you know and you’ll get the idea of how much food you’d actually need to eat to grow this tall.

The hormonal havoc of puberty is another classic example of how hormones dictate body shape. Before puberty, boys and girls tend to have a very similar amount of body fat and muscle, but under the direction of sex hormones boys lose fat during puberty and gain muscle, while girls lose muscle and gain fat around the thighs, breasts and buttocks. Why don’t girls put on fat evenly all over their body? Why does fat seem to accumulate around the stomach area first and not the forehead or hands? Because hormones tell their body where the fat is to go — it’s not a random process. The primary regulator of fat metabolism is a hormone called insulin. Insulin is the culprit that puts fat into your cells and keeps it there.

Insulin: the fat hormone

Most people know of insulin only in the context of diabetes. Insulin allows sugar or glucose from food to enter your cells to be turned into fuel. If you had no insulin, the sugar would stay in your blood and your cells would literally starve to death, unable to produce energy. When your body cannot produce enough insulin or you become insensitive to insulin, you have a condition called diabetes. So what happens if you have too much insulin?

It’s been known since the 1960s that if you want to lose fat you need to lower your insulin levels. If insulin levels are too high, the hormones whose job it is to get the fat out of your cells cannot work. The ACCORD study published in 2008 in the New England Journal of Medicine found that type 2 diabetics treated with insulin actually got fatter than the control group over a 12-month period. Around one-third of the insulin-treated group gained over 10kg.

Insulin has been used in the past to treat anorexia. In the 1940s a study titled Obesity and Leanness published in the Journal of the American Medical Association found that anorexic patients gained as much as 2.7kg a week on insulin therapy.

Insulin makes us fat by opening up the channels in fat cells that allow them to absorb fat. More insulin equals more fat being absorbed into fat cells, so if your body is producing too much of this hormone you’re going to get fatter. If you eat fat in the absence of insulin, the fat cannot enter your fat cells.

What causes high insulin?

Every time you eat carbohydrates your pancreas produces insulin. More carbs equals more insulin equals more fat being stored in fat cells. In a cruel twist of fate, as a result of a modern diet high in sugar and also as a natural result of the ageing process, your cells slowly but surely become immune to the effects of insulin.

After eating a meal you have sugar in your blood that needs to be moved into your cells, but your cells are ignoring the insulin, so your poor overworked pancreas releases even more insulin to try to get the job done. More insulin opens up more channels in your fat cells and allows them to absorb more fat. Remember that high insulin also blocks the effects of the hormones that direct your cells to release fat. So you’ve got fat cells absorbing more fat and not able to release any. Pretty soon those fat cells are going to be bulging at the seams. The first step in reducing levels of insulin is to restrict, or at least change, the type of carbohydrates you eat. Start by eliminating all sugar from your diet.

Sleep deprivation can also increase insulin levels. Researchers have noted for some time that not getting enough sleep is associated with getting fatter. Insulin levels tend to be naturally higher during the day when we’re eating and storing fat ready to be used at night while we’re sleeping and insulin is lower. Most people think of sleep as a passive process, but your body is actually working extremely hard while you sleep. During sleep, your body heals, repairs, detoxifies and builds new hormones, neurotransmitters and enzymes, all of which takes a lot of energy. Since you don’t eat for energy while you’re sleeping, the very low insulin levels allow other hormones to move fat out of fat cells to be used as energy for your body while you’re sleeping. Burning the candle at both ends gives your body extra fat-storing time.

Sleep problems are often associated with metabolic syndrome or chronically high insulin. Despite your fat cells being stuffed full of energy, overly high insulin levels prevent it being released for your body to use while sleeping. If you find yourself waking at night feeling hungry despite a good-sized dinner, this is the reason why.

Alcohol does not have a direct effect on insulin levels; in fact, it’s treated by your body more like a fat than a carbohydrate, but it does speed up and increase insulin resistance. The more resistant you are to insulin, the more of it you’ll produce each time you eat carbohydrate. By becoming insulin-resistant you’ll have a big response to even a small amount of carbohydrate. Muscle loss from dieting or illness can also speed up insulin resistance.

Unfortunately, fat seems to beget fat. Remember that fat is a fully functioning organ just like your liver or kidneys. Abdominal fat in particular can secrete chemicals that impair your glucose tolerance and increase insulin levels.