Could your diet be stopping you from reaching your goals?
Losing weight and looking more toned is one of the most common goals of people going to the gym. Maybe it’s in preparation for a big event like a wedding or family event, maybe it’s in preparation for the summer. For some people losing the weight is much easier than it is for others. Some people may lose a few pounds then hit a wall, while some people have been stuck at the same weight for what seems like forever and are wondering why they can’t seem to lose weight. They exercise, they heavily restrict calories and still the scale doesn’t move and the waist line doesn’t change. To understand why this happens it is important to understand the process your body goes through when on a diet. Every change to your diet has a corresponding effect in your body.
Our bodies are wonderful machines that have many chemical reactions going on at any given time. They really are works of art. The complexity of these processes are enormous. Many of these processes are necessary for our survival and these processes can sometimes work against us. Our body stores excess calories within fat cells in order to provide us energy when we need it (during times of starvation). Due to our society’s general decrease in overall activity and the existence of very tasty high calorie, heavily processed food it is easy for us to end up storing a lot of energy. In order to get the body to use this energy we need to intake less and burn more through activity. So many people will begin restricting the amount of food they eat and will begin exercising.
However, when we restrict food and begin burning more energy than we are taking in a number of changes happen within our body that ultimately can work against us. Let’s start with the hormone Leptin. Leptin is produced by fat cells. Essentially the more fat you have the higher the leptin levels in your blood will be. This provides feedback to your brain (more specifically the hypothalamus) telling it how much stored energy you have. When Leptin levels are high appetite tends to be suppressed although some people with a large amount of excess adipose tissue may become leptin resistant. If someone develops leptin resistance it throws off the body’s way of monitoring stored energy, causing people to feel hungry when normally leptin would be signaling the body that it has eaten enough.
When you begin to burn fat through diet and exercise Leptin levels drop, the brain realizes that the body is burning through its energy stores and many changes start to take place in order to try and conserve as much energy as possible. When dieting there are a number of hormonal changes that take place. Leptin levels lower as does testosterone, insulin, and thyroid hormones. Hormones that elevate are cortisol, ghrelin, growth hormone and catecholamines. These are all important hormones for regulating the human body and its composition.
Ghrelin: Is a hormone (along with others) that play a role in both hunger and appetite. Raising ghrelin levels tends to make people get hungry and stay hungry, leading to you thinking about food constantly.
Cortisol: Is a catabolic hormone that enhances protein breakdown as well as stimulating the conversion of protein to glucose in the liver. Cortisol breaks down both dietary protein and protein contained within muscles. Want to be a smaller, fatter version of yourself? Cortisol will help with that.
Testosterone: Helps maintain a lean body and may have a positive effect on both cardiovascular and diabetes risk profile.
Thyroid Hormones: The hormones we are focused on are T3 and T4. High blood fatty acid levels tend to impair the uptake of T4 into the liver. There are also changes that happen in liver metabolism that impair the conversion of T4 to T3 (active thyroid). The resulting drop in T3 levels help contribute in combination with the other drop in hormones to slow down metabolism.
Insulin: Regulates blood sugar and promotes the storage of glucose for use as energy later. A drop in insulin promotes fat mobilization (for use as energy) but it can cause other problems. Insulin is anti-catabolic to muscle and helps prevent muscle breakdown. Also, a reduction in insulin results in testosterone being able to bind with sex-hormone binding globulin better. This lowers testosterone levels.
All these adaptations are your body’s attempt to slow the rate of fat loss and to prime the body to put weight back on at an accelerated pace. Numerous studies have shown that often people put back on all their original weight and often even more weight following a diet. Other studies show that extremely low calorie diets are particularly bad when it comes to maintaining weight loss. This could be due to the numerous hormonal changes that take place in combination with excessive restriction leading to overindulgence.
So is dieting hopeless? Impossible? The answer is of course No. However, fad diets, crash diets and many of the popular diets that have been commercialized by supplement companies will often ultimately end up in failure. When executed poorly or without proper oversight and advice they can lead to changes within your body that make your goals difficult if not impossible to obtain. For long term success emphasize altering your lifestyle to make healthier choices will eventually reach your goals and maintain them without the negative side effects. Remember that old story about the turtle and the hare? Slow and steady wins the race. Be consistent, don’t look for a silver bullet it doesn’t exist. It will take time, but with the right combination of exercise and diet choices you can get there and if you need help, we can help you get there.
To your success,
Keegan Marshall CPT, CES, FNS
1 Klok, M. D., Jakobsdottir, S. and Drent, M. L. (2007), The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review. Obesity Reviews, 8: 21–34. doi:10.1111/j.1467-789X.2006.00270.x
2 Britt Edén Engström, Pia Burman, Camilla Holdstock, and F. Anders Karlsson, Effects of Growth Hormone (GH) on Ghrelin, Leptin, and Adiponectin in GH-Deficient PatientsThe Journal of Clinical Endocrinology & Metabolism 2003 88:11, 5193-5198
3 Mårin, P., et al. “The effects of testosterone treatment on body composition and metabolism in middle-aged obese men.” International journal of obesity and related metabolic disorders: journal of the International Association for the Study of Obesity 16.12 (1992): 991-997.