How to Improve Your Insulin Sensitivity
Recently, a lot has been written about the role of insulin sensitivity in weight gain and weight loss with many attributing it as a key to health, longevity and enhanced mental and physical well-being. Insulin is a hormone secreted by the pancreas and its main function is to facilitate the entry of glucose into the cells where it is stored for future use. This helps lower and maintain blood glucose at a stable level that is important for the smooth functioning of all the body process. Below we will detail some of the key things to know about insulin sensitivity and why it is important to your health.
Insulin sensitivity refers to the ability of the body to use the insulin produced by the pancreas in the most effective manner. High insulin sensitivity ensures that the body responds to minimal levels of insulin and is able to successfully maintain blood glucose levels in the normal range. It also means that all the cells in the body are being supplied with adequate quantities of glucose to carry out their respective functions.
How does Insulin function?
Insulin has several functions, the main among them being the metabolism of carbohydrates. When you eat food high in carbs, the digestive system breaks it down into glucose and releases it into the blood stream. The raised glucose levels in the blood trigger the secretion of insulin by the pancreas to help the excess glucose enter the cells to be stored for future use. Insulin does this by attaching itself to receptors on cell walls, increasing the cell’s receptivity to glucose, thus allowing it to enter. This clears the excess glucose from the blood, restoring the levels of glucose and insulin to normal levels.
Why is insulin sensitivity so important?
If the body shows resistance to insulin, the pancreas will have to produce the hormone in abnormally high quantities to bring down the blood glucose levels. This occurs when insulin, for some reason cannot attach itself to the cell receptors, or encounters fewer cell receptors than are required. This drastically affects the capacity of cells to take in the glucose, leaving them wanting in nourishment. As the glucose cannot be pushed into the cells, its levels in the blood begin to spike. This in turn triggers the release of more insulin to control the glucose levels. That is how lowered sensitivity to insulin leads to high levels of glucose and insulin in the blood which becomes a potentially dangerous combination for the body to handle.
Clues to determine your Insulin Sensitivity
- On high-carbohydrate intakes, do you find yourself getting pumped and full or sloppy and bloated? If the former, you have good insulin sensitivity; if the latter, you don’t.
- When you eat a large carbohydrate meal, do you find that you have steady and stable energy levels or do you get an energy crash/sleep and get hungry about an hour later? If the former, you probably have normal/low levels of insulin secretion; if the latter, you probably tend to over-secrete insulin which is causing blood glucose to crash which is making you sleepy and hungry.
What are the risks associated with low insulin sensitivity?
Decreased insulin sensitivity could result in hyperinsulinemia and hyperglycemia. The excess insulin in the blood stream can damage the blood vessels, increase risk of heart disease, blood pressure, obesity accelerated ageing and even cancer. The high glucose levels can cause blood clots, kidney malfunction, nerve damage, eye disease and compromised cardiovascular health. Resistance to insulin is the characteristic of type 2 Diabetes but can be a feature of type 1 diabetes too leading to what is known as “double diabetes”.
The possible causes of reduced insulin sensitivity
The most universal cause of insulin resistance is believed to be aging but other lifestyle factors such as poor dietary habits and lack of physical activity also play a role. Following are some of the main causes of reduced insulin sensitivity:-
- High intake of refined sugar and processed food
- A high carb diet
- Excessive consumption of alcohol
- Sedentary lifestyles
Improving Insulin sensitivity
You can see from the graph below (adapted from Dilman and Bobrov) that insulin sensitivity decreases with age.
The good news is that you can improve insulin sensitivity by adopting specific measures associated with diet and exercise. Key steps are highlighted below.
Have Carbs with low glycemic index
Glycemic index is a measure of how a particular food impacts blood glucose levels. Foods that result in a rapid rise in blood sugar levels, triggering the secretion of excessive insulin, are said to be high glycemic. Foods with a low glycemic index, on the other hand, do not cause a sudden spike but promote a steady, controlled release of glucose and insulin. Prolonged and regular consumption of high glycemic foods causes the cells to develop resistance to the huge quantities of insulin secreted, which means that still more insulin is required to bring down the blood glucose levels. To counter this tendency, eating low glycemic foods as part of your diet would help to improve insulin sensitivity and facilitate absorption of the glucose by the cells.
|Glycemic Index of Select Foods (With Glucose as the Standard of Comparison)|
|White rice, instant||91|
Non starchy foods that are rich in fibre and a diet rich in protein and fats would make for good a dietary choice.
Diets that are extremely low in carbohydrates such as the Atkins diet are believed to bring about a reversal of hyperinsulinism and promote fat loss. This happens because of a shift in the body’s energy supply from a glucose based one to a fat based one –where the body utilises its stored body fat (lipolysis). The insulin levels drop within two days leading to the metabolic shift. Triglycerides are converted into free fatty acids and then further broken down into compounds known as Ketone bodies to be used as fuel by the brain and muscles.
Incorporate exercise into the lifestyle
Exercise improves the ability of muscle cells to store glucose without the help of insulin. This increases insulin sensitivity and promotes better metabolism of glucose. The best type of physical activity that would give great results would be to combine aerobic activities such as cycling, jogging, swimming etc with weight training. The former helps to improve cardiovascular fitness and the latter (weight training) build muscles which in turn increases possible insulin receptor sites and uses glucose while exercising. Many studies have clearly shown how even 30 minutes of moderate activity effectively improved insulin sensitivity in just six months.
Include Omega 3 Fatty acids in your diet
We need an equal ratio of omega 3 and omega 6 fatty acids in order to improve insulin sensitivity and lower triglyceride levels, but modern western diets have a skewed ratio of 20:1 in favour of omega 6. Make sure you consume foods like salmon, tuna, walnuts, flax seeds and eggs to even out that ratio.
The higher the fibre intake, the lower the insulin resistance and risk of diabetes. Fibre lowers the glycemic index of the food, providing the body with a slow and steady supply of glucose.
Limit fructose in your diet
Fructose, better known as fruit sugar is also present in processed food sources containing high-fructose corn syrup. The liver is responsible for metabolising of fructose, however in large quantities, fructose leads to accumulation of triglycerides, in turn resulting in decreased insulin sensitivity. It’s the fructose from processed foods that is usually the culprit so you don’t really need to cut down on your consumption of fresh fruit.
Avoid processed, instant foods
These foods almost always cause insulin resistance, leading to weight gain, increasing susceptibility to diabetes.
Add Vitamin E and K to your diet
Vitamin E enables absorption of glucose, thus promoting insulin sensitivity. Nuts and seeds are rich in the vitamin and you do not really need to supplement it artificially. Vitamin K is also known to play an important role in insulin metabolism by slowing the tendency of insulin resistance. (http://www.nutraingredients.com/Research/Vitamin-K-help-for-diabetes)
Other ways to improve insulin sensitivity are weight loss, sufficient sleep, stress and medication.
To summarise – recent research has revealed that low insulin levels in the body give rise to amazing health benefits from delaying aging, increasing energy and vitality and promoting cardiovascular health. Improving insulin sensitivity could be key to preventing not only diabetes but many other ailments that have stemmed from lifestyle related causes.