by ICANS Editorial Team
Most people are familiar with the hormone insulin and the fact that it regulates blood sugar levels. What you might not know is that how sensitive your body is to insulin predicts how much body fat you will lose from different kinds of diets. For example, people who have higher insulin levels and greater insulin resistance will lose more body fat from a low-carb diet than a low-fat diet because carbohydrate restriction restores the cell’s sensitivity to insulin.
This tip will explain why that is and provide additional information about the two phases of insulin release so that you can successfully manage your blood glucose and achieve optimal body composition.
If you are familiar with insulin, you probably know of it as a storage hormone that regulates blood sugar levels. When you eat, carbohydrates are absorbed into the blood as glucose. The body regulates blood glucose levels by releasing insulin from the pancreas. Insulin acts as “key” binding with receptors on your cells so that they can use glucose for energy. Any extra glucose that can’t be used for energy is stored as body fat.
It is this relation between insulin and fat storage in the body that makes insulin sensitivity a primary predictor of fat loss. For example, a recent trial classified women as “insulin resistant” or “insulin sensitive” and put them on either a low-fat, calorie-restricted diet or a low-carb diet. The low-carb diet didn’t require calorie restriction due to the fact that the women in the low-carb group naturally ate much fewer calories than normal.
Among the insulin resistant women, only those on the low-carb diet lost any fat. They reduced body fat percentage by an average 2.3 percent. The women who were classified as insulin sensitive lost roughly the same amount of body fat regardless of whether they were on the low-carb or low-fat diet (the low-carb group lost an average 3.2 percent body fat and the low-fat group lost 2.7 percent, which is not a statistically significant difference).
We can make a few conclusions from this study and related research:
- If you are insulin resistant, following the traditional “diet” that is calorie restricted but high in carbohydrates will actually undermine your ability to lose body fat.
- If you are very insulin resistant, cutting carbs a little bit, or playing around with small reductions in your glycemic load probably won’t have any effect. You need a more radical approach to reset your metabolism.
- People who are sensitive to insulin have a lot more flexibility in the type of diet they use to lose body fat. This suggests that the key is to optimize insulin sensitivity first.
How can you do this?
The first step is to get your phase 1 insulin release in top notch shape. Scientists have identified two distinct phases of insulin secretion. Phase 1 insulin release involves the secretion of insulin that is already made and stored within the beta cells of the pancreas. The first phase occurs quickly, within the first few minutes after blood glucose levels rise and lasts about 10 to 15 minutes.
Phase 2 is a slower, more prolonged release of insulin that requires the pancreas to make new insulin. It takes time to get going and can’t be relied on for effective glucose management if phase 1 conks out over the longer term.
Phase 1 insulin release is extremely important because it keeps blood glucose levels in a tightly regulated range and avoids spikes and valleys. Keeping blood sugar relatively steady is important to maintain energy levels, optimize brain function, and minimize hunger between meals. It also means you will have less inflammation and allows for better body weight management and peak physical performance.
How can you know if your phase 1 insulin release is optimized?
The GlycoMark is a clinical test that is used to measure phase 1 insulin and identify if you have high glycemic variability in response to meals (large peaks and valleys in blood sugar levels).
Getting a blood glucose meter is a practical way to test your blood sugar at home before and after eating. The smaller the increase in glucose from pre- to post-meal, the better your phase 1 insulin release and glucose management in general.
Want to learn more about how to optimize blood glucose regulation? The Nutritional Medicine Profile (NMP) course teaches an integrated approach to managing glucose and insulin for long-term health and physical performance. Nutrition, exercise training, lifestyle, and supplementation strategies are covered along with diagnostic testing to monitor and assess progress.
McClain, A., et al. Adherence to a Low-Fat versus Low-Carbohydrate Diet Differs by Insulin Resistance Status. Diabetes, Obesity, and Metabolism. 2013. 15(1): 87–90.