Survival of the Fattest
Why do we have so many fat cells? The answer is simple - to protect our big brains. We have abundant capacity to store fat to ensure a readily available source of fuel for the brain. Human brains comprise a measly 2% of our body weight but they are energy hogs - burning 20% of the calories used by the body. Furthermore, like the heart, the brain is always on, always hard at work, even while we sleep. Fat stores are insurance that the fuel tank won’t run dry. Adequate reserves are so important that human babies are the only land animals born fat.
The Perils of Over-Packing
Our body and brain need a continuous supply of fuel but not a continuous supply of food. We eat intermittently, which means we are always either in the fed or or fasted state. In the fed state the body can is able to stockpile extra fuel in two ways -- a quick energy fuel called glycogen which is stored in the liver and muscle cells or long term fuel storage in adipose tissue (what we call fat).
You can think of glycogen stores and fat stores like an carry-on overnight bag and a great big suitcase. Because most people have access to regular meals they no longer need the backup of large fat stores. We can easily exist on what is in our overnight bag but we keep adding more pounds to that big bag as if we still lived in time when feast and famine were the usual way of life. Now we are paying the price for those overweight suitcases just as you do at the airport.
The secret to losing is to stop gaining
Although diet and exercise can result in weight loss the results are usually short-lived. Lost pounds nearly always find their way back home - often with a little extra for good measure. It’s time to discard this ultimately doomed strategy of weight loss. If we want to achieve a healthy weight that lasts a life time we must stop accumulating.
We know all about dieting but have forgotten (or never learned) how to eat. Over the course of the average human lifespan a person consumes over 30,000 pounds of food which is more than 50 million calories. We have a built in mechanism to keep our weight stable and for most of human history that is exactly what happened. Just as camels have adaptations to allow them to go for long periods of time without water, humans have an ability to eat and store a lot a fuel to get them through periods of food scarcity. The modern environment for many of us is now one of abundance --- so it’s time to change strategies. To do that we need to use that big brain. Check out my next post on “putting your cortex in control”.
