Somewhere along the way insulin got a really bad rap. The world is now blaming the “insulin fairy” for fat gain & suboptimal metabolism. Let’s take a second to unpack what insulin really is, why we need it, and how this affects how we should eat.
Insulin is an anabolic hormone secreted in the pancreas. It circulates through the blood and acts as a key that allows glucose into the cells of the body to be used as energy. Abnormally high circulating levels of insulin are unhealthy, but insulin in general does not make you fat and is not a “fat hormone” but a “nutrient storage hormone”. Without it, there is no energy and for sure no muscle building. We want healthy levels of insulin and insulin sensitivity, not insulin resistance.
Insulin resistance (IR) is a condition where the body’s cells are not as responsive to insulin, causing circulating glucose to remain in the bloodstream. A caloric surplus leading to fat gain will cause fat cells to increase in size & become more resistant to insulin. Increased levels of free fatty acids accumulate in the blood, becoming the body’s preferred energy source (resulting in glucose not being used properly). Glucose and insulin levels in the blood rise. The body’s glycogen stores are not properly replaced, which can lead to greater appetite and continue the cycle. IR can eventually lead to Type 2 Diabetes, but it is important to note that IR does not lead to weight gain in the absence of a caloric surplus, though it can alter one’s fuel usage and energy production.
Many people assume that eating a higher-fat, lower-carbohydrate diet will help with weight loss due to the decreased need for insulin secretion. Truth is- any calorie deficit will lead to weight loss, and weight loss improves insulin sensitivity!
So how can you improve your insulin sensitivity?
-Stay active with weight training and cardio
-Build more muscle
-Get adequate sleep (at least 7hrs/night)
-Work to reduce stress in your life
-Avoid constant snacking
-Maintain a caloric deficit for weight loss if appropriate
-Katy Hair, RD, LDN, CPT
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