Without even knowing the science behind what really causes you to lose and gain weight, our Paleo ancestors ate what can be referred to as “the perfect diet.” They didn’t go to the internet and Google the latest fad diet. They didn’t count calories. They didn’t worry about balancing their energy in/energy out equation.
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Modern science has found that losing weight is much more complex than the energy balance equation predicted. The 3500 calories per week deficit that each person is instructed when attempting to lose weight simply doesn’t work. Look around you. Do the people that you know who have tried this approach lose and maintain weight? Have you ever been successful using this approach? The answer is most likely a resounding “NO!” People don’t necessarily lose weight because they determine the amount of energy or calories they consume and then forever stay under this number of calories (right or wrong) for a lifetime.
What recent research suggests is that hormones and the type of foods we eat are far more important than the amount of food we eat or the calories contained in a given meal when determining whether we gain weight or lose weight.
Fat Flows In and Out of Cells
Fat, either in the form of dietary fat or fat stored in our body, is constantly flowing into an out of our cells. Fat is either used for fuel when it is circulated in the body or it is returned to the cells. The reason that you are overweight or carrying excess fat in your body is because you are storing fat in your cells and not burning it for fuel. Our body stores fat in our cells in the form of a triglyceride. Recall from earlier that a triglyceride is formed by three fatty acids and one glycerol molecule. Triglycerides, in their capital “E” structure, are too large to freely flow in and out of your cells. They must be broken down into their fatty acid components and released into your system to be used as fuel. Fat storage in the body acts as a way for your body to deal with the excess energy you consume from your meal.
When you think about eating or feel the urge to eat your body begins a complex but predictable process. First, upon thinking about food, your body begins secreting a hormone called insulin. Insulin, which is secreted from your pancreas, is the primary hormone that controls your blood sugar or the level of glucose in your body. Insulin also acts as the gatekeeper to fat cells, determining when triglycerides will be broken down into fatty acids and released into the bloodstream to be burned as fuel or when fatty acids will be transported into the cell for storage as a triglyceride. When you think about eating a meal, insulin is secreted in your blood stream. This makes you hungry and you start eating.
Typically, your meal will consist of a mixture of carbohydrate, protein and fat. Set aside the effect of protein on your body for a second and focus just on carbohydrates and fat. Once you have started eating the body produces more insulin. Fat is digested and immediately sent to the fat cells for storage so that your body can deal with carbohydrates. Carbohydrates, in any form, are easily digested and enter your bloodstream as glucose. The presence of glucose causes your blood sugar to rise. Your body produces even more insulin because of this rise in blood sugar from the presence of digested carbohydrates.
Insulin kicks in and determines how your body will deal with the blood sugar in your system. Because too much glucose in the bloodstream can be toxic, digested carbohydrates are always dealt with first before fat or protein. Some of the glucose in your system will be immediately burned for energy by your cell. Some of the glucose will be stored in the liver and muscles. Any remaining glucose will be immediately converted to fatty acids and stored in the fat cells.
In sum, you gain fat because you have more fat stored in your cells. Insulin determines whether fat is liberated from these cells to be burned as fuel or stored for later use. The presence of glucose in the blood after eating is the primary driver behind insulin. And the level of glucose in your meal is directly determined by the amount of carbohydrates you consume.
To make weight gain equation even simpler, carbohydrates drive insulin and insulin drives fat storage.