Intermittent Fasting – A Tool for Weight loss?

By Caroline Cederquist, M.D.

Over the past few years there has been some buzz about a pattern of eating called intermittent fasting. Advocates of intermittent fasting recommend that you go anywhere from twelve to twenty-four hours without eating any food or drinks other than water. Various recommendations suggest fasting for anywhere from sixteen hours every day, and eating all other meals during a shorter time frame such as between 8 AM and 4 PM, to recommendations to fast completely every other day, and everything in between.

Intermittent fasting is not a diet but a pattern of eating that allows for eating whatever you want, but only at certain times or on certain days. Advocates state that this pattern of eating allows for both fat loss and gaining of muscle mass. One popular website states that fasting helps you lose weight because it decreases the amount of time your body is in the “fed” state. After eating (the fed state), your body secretes insulin in order to move glucose into your cells for energy. After several hours, glucose and insulin decrease and if more energy is needed, glucose is liberated from storage sites in your liver, your muscles and from your fat tissue. Proponents of fasting feel that the more you are in the fasting state, the more you will break down fat to meet your energy needs.

The problem with this explanation is that an important metabolic phenomenon occurs in the majority of people who are overweight. As a weight management physician who actively monitors glucose and insulin levels, I find evidence of this metabolic issue in 90% of my patients.

If you gain weight, especially belly weight, your metabolism becomes dysfunctional and your cells no longer respond the same way to insulin. Medically, we say that your cells become resistant to the action of insulin. Even though you are making insulin, when it attaches to your cells, it does not produce the changes in the cell that allows glucose to enter. Your body responds by secreting much more insulin at all times, whether you are in the fed or the fasting state. Many of my patients have very high insulin levels, sometimes even ten times the normal level, despite a twelve hour fast.

What I have found to be highly effective in reversing this metabolic dysfunction, is to place my patients on a structure of eating where they will eat lean protein every 3-4 hours along with low glycemic carbs and healthy fats. It is the opposite of fasting as I recommend more frequent but smaller meals.

Proponents of intermittent fasting do not recommend any specific balance of nutrients be consumed at the two meals people may eat per day. For someone with insulin resistance, I can assure you that eating higher carbohydrate meals without a focus on adequate protein within any time window, will lead to weight gain and fat gain.

I also must take issue with the claim of intermittent fasting to cause muscle growth. Your body does not have any capacity to store protein. The only place it exists is within your own muscles. Even after a normal overnight fast when you are sleeping, your body is breaking down muscle tissue to obtain needed amino acids that you need to replace from your diet. This process, called protein turnover, is always occurring. Ensuring the regular intake of lean protein allows muscle to be maintained even within the weight loss process. If you fast, even if your diet contains quality protein, you will be breaking down muscle for the majority of the day. This will of course be intensified if your diet quality is not as good and is deficient in protein.

A further concern with intermittent fasting for weight loss is that it can set up disordered eating patterns in some people vulnerable to this. Some people can do well with the longer periods of food restriction recommended with intermittent fasting but others may develop binge-like behavior in the hours when food is allowed.

Through years of clinical experience, I have found that the pattern of structured eating of the right amounts of nutrients is the most effective strategy for long term weight management. After as soon as six weeks on a meal plan with the regular intake of lean protein and a controlled amount of carbohydrate, fat and calories, my patients usually show significant improvements in both insulin and glucose levels which indicate a more healthy, functioning metabolism. We are also able to monitor muscle mass with a body composition analyzer which shows that muscle is retained while fat is lost.

There is however, a role for intermittent fasting in healthy weight management. Once blood sugar and insulin levels are controlled, going longer periods without food, such as a fast from 7 PM at night to 9 AM in the morning allows a 14 hour fast where the body is able to take a break from metabolizing food and allow the clean up process called autophagy which allows our bodies to get rid of damaged cells. Also, once blood sugar and insulin levels are stabilized, moving to three meals a day within a ten-hour period of time is both convenient and effective for long term weight management as long as the diet quality of lean protein, complex and healthy carbs and healthy fats is maintained.

Cederquist Medical Wellness Center

239-734-4486
1575 Pine Ridge Road, Suite 19

Naples, FL 34109