HOW INSULIN IMPACTS YOUR HEALTH
When you are looking to optimize your health or are dealing with blood sugar problems, one word that comes up constantly is insulin .
This hormone has a HUGE impact on your metabolism and therefore on your overall health.
However, the concepts of "sensitivity" or "resistance" to insulin, mixed with terms related to blood glucose, can sometimes be confusing, and that is what we will clarify here.
WHAT IS INSULIN?
Definition
Insulin is a hormone produced by the pancreas that regulates the level of glucose (sugar) in your blood.
It acts like a kind of key , a signal : it allows glucose to leave the bloodstream to enter the cells of your body and be used as energy.
Without insulin, your blood glucose level therefore remains high, which has several bad consequences for your health .
When circulating sugar exceeds what your body can use, it converts it into fat .
Furthermore, you will have more difficulty burning these fats and using them as an energy source.
High blood sugar slowly damages proteins and tissues, which accelerates certain aspects of internal and external aging.
Excess sugar overloads highly sensitive cells such as those of the nerves , eyes , and kidneys .
This can cause tingling or loss of sensation, gradually weaken vision and wear out the kidneys more quickly.
Excessive blood sugar gradually damages blood vessels, making them more rigid and disrupting circulation, which in the long term increases the risk of cardiovascular problems or diabetes .
Simply put : insulin is essential because it allows your body to convert sugar into energy and prevent hyperglycemia.
ROLE IN YOUR BODY
How does insulin work?
After a meal, insulin increases and signals different cells (muscles, liver, adipose tissue, etc.) to capture glucose to make energy .
Insulin helps to convert glucose into glycogen , an energy reserve that your muscles use when you exert yourself.
They account for 70–80% of glucose elimination after a meal.
Insulin also helps to produce glycogen to create a reserve of sugar available when your blood sugar drops, especially several hours after a meal.
Insulin allows the conversion of excess glucose into fat , in order to store excess energy when other reserves are already full.
After this active phase, insulin levels must decrease rapidly to avoid prolonged hyperinsulinemia . This is only possible if blood glucose returns to normal levels quickly enough.
In a healthy person, insulin lowers blood glucose levels in approximately 2 hours.
SENSITIVITY AND RESISTANCE
What does that mean?
Insulin sensitivity is the ability of cells to respond to the insulin signal.
- If a cell is very sensitive , a small amount of insulin is enough to allow glucose to enter.
- If it is not very sensitive , it needs much more insulin to achieve the same effect.
Insulin resistance therefore corresponds to a very low sensitivity of the tissues.
If we return to the image of the key , insulin resistance would correspond to a rusty lock that prevents the channel from being opened.
Consequences of resistance
As a reminder, muscles account for 70–80% of glucose elimination after a meal.
When they become resistant, a large part of the released glucose therefore remains trapped in the blood !
This causes the pancreas to react by secreting more insulin to force glucose into the body.
Since your muscles are not receptive, it is your liver and adipose tissue that end up managing the excess: they transform the excess glucose into fats .
Especially since, when insulin is high, your metabolism uses fats less efficiently as an energy source.
So there is a double effect : you store more fat and you burn less.
This is why having consistently high insulin levels leads to weight gain.
Even if your fat and liver recover the excess unabsorbed glucose, the amount is too large to clear the glucose from your blood => your blood sugar increases.
There is also a double effect here: when you become insulin resistant, your liver continues to release glucose even though your blood sugar is already high, making the situation even worse.
In summary
Insulin resistance has the following consequences:
Which causes fat storage, inflammation and appetite disturbances, facilitating weight gain.
Which causes, among other things, premature aging, weakened immunity and an increased risk of cardiovascular disease.
FACTORS IMPACTING INSULIN
The major factors that will have a significant influence on your insulin and metabolism
Exercise, and in particular the development of muscle mass, is one of the most effective ways to improve your sensitivity.
The muscles used increase their ability to capture glucose, and, even without weight loss, a workout makes cells more responsive to insulin for several hours .
This is surely the most important factor.
Foods with a high glycemic index (sweets, breads, refined pasta, etc.) cause sharp rises in blood sugar and put a lot of strain on insulin, which, over time, can reduce sensitivity.
Conversely, a varied diet, with a moderate dose of carbohydrates and rich in fiber (fruits, vegetables, whole grains, legumes) stabilizes blood sugar and promotes good sensitivity.
This is one of the main reasons for the growing popularity of ketogenic/low-carb diets.
Chronic stress raises hormones like cortisol, which keep blood sugar high and weaken insulin sensitivity.
Lack of sleep tends to facilitate stress, cause appetite disturbances (you end up eating more, more sugar) and disrupt your circadian rhythm (indirectly impacting insulin).
Good sleep therefore facilitates the management of hormones, stress and appetite.
MONITOR YOUR INSULIN
In summary
Bi-optimizing your insulin allows your metabolism to function at its best.
It facilitates your performance and recovery thanks to a better distribution of glucose in your muscles.
This ensures better management of your body fat , which will indirectly impact your health and longevity.
FAQ
Simple tests such as fasting blood glucose , fasting insulin and the HOMA-IR index provide a good indication.
The higher the fasting insulin level is for a normal blood sugar level, the more it suggests that your body is working harder to manage sugar, a sign of the beginning of resistance.
No.
Although its main function is the regulation of blood glucose, insulin also influences the metabolism of fats and proteins : it promotes the synthesis of fatty acids and inhibits their breakdown, and it participates in the production of new proteins in various cells.
Insulin is an anabolic hormone: it facilitates the storage of nutrients in cells, including amino acids in muscles.
It doesn't build muscle on its own, but it creates an environment conducive to recovery and growth. Proper insulin sensitivity therefore indirectly helps optimize muscle gain.
Yes.
Sport, especially weight training and high-intensity efforts , increases the muscles' ability to absorb glucose without even needing insulin.
In the long term, this greatly improves insulin sensitivity, even without dietary changes.
No.
Carbohydrates stimulate insulin the most.
Proteins make it rise a little, especially to promote muscle recovery.
Fats , on the other hand, trigger very little insulin.
This is why a carbohydrate-free meal maintains stable blood sugar levels and avoids a significant insulin spike.
Because even without meals, the liver naturally releases some glucose into the blood to fuel the brain and vital organs.
In people who no longer produce insulin (as in type 1 diabetes), this glucose accumulates: they therefore need a small dose of basal insulin to maintain stable blood glucose.