Insulin and it’s effects.

A presentation given by May Lauder - a third year Kevala Nutritional Therapy Student

I am going to talk today a little about the effects that the hormone called insulin has, or rather the effects that excess insulin has on our health. As you know insulin is excreted from the pancreas into the bloodstream every time that we eat and it is supposed to move the blood sugar into our cells where it is burned as fuel, but how much insulin is released depends on what we have eaten, as one of it’s roles is to regulate blood sugar.

The more natural diet that our ancestors would have eaten, which would have consisted of any meat or fish that they may have caught, along with fresh fruits and vegetables that were in season at the time would have given them a trickle charge of glucose into the bloodstream that would have just been enough to give them the energy to go about their daily activities and for finding the next meal. This trickle charge of glucose would have initiated a fairly stable insulin response.

Insulin is basically a storage hormone and so in our ancestors times it would have been used by the body to store any excess calories from carbohydrates as fat in the body in case there were times of famine, so that would in effect be the body’s reserves for when things got tough and there wasn’t so much food around.

Today our diets have come a long way from this and very rarely do we have  to deal with famines etc (not in the West anyway), the opposite is now true, we have an abundance of food and people tend to over eat, on top of which they lead very sedentary lives having little in the way of exercise. Our diets tend to consist of a lot of convenience and processed foods, which contain mostly refined carbohydrates and as these are converted very quickly into glucose it gives us a sudden surge of glucose into the bloodstream.  

Insulin is then needed to regulate the blood glucose level and keep it from getting too high which can be dangerous. If large amounts of carbohydrates or sugars have been eaten then this will cause a sudden surge of insulin as it tries to regulate this situation as quickly as possible. This sudden surge of insulin quickly brings blood sugar levels back down into the normal range but because of the rapid ness of this blood sugar levels often quickly fall down too low causing a yo-yo effect of highs and lows. These rapid fluctuations are not good for us because of the stress that they place on the body.

Can you see how the role of insulin has changed from originally being basically a storage hormone to it’s role today of trying to regulate blood sugar levels, we have not adapted to our modern diets which are very high in carbohydrates and even worse most of it is processed and fibreless which means that the conversion into glucose will be very quick.

The highs and lows that sudden surges of insulin cause is known as hypoglycaemia, the symptoms of which can be typical of the early symptoms experienced by chronic fatigue sufferers, in particular fatigue. This is because glucose is the main fuel of the body, so low blood sugar will produce symptoms of physical and mental fatigue. Insulin maintains the sugar levels within our cells where we create energy, but if we can’t get glucose into the cells because they have become resistant then we become tired more easily. I will talk a little more about insulin resistance later on.

 Insulin first encourages our tissues, especially the muscles to try and use up this glucose as it is toxic and burn it for energy, it works by opening channels on cell membranes allowing glucose to travel from the blood into the body’s cells, any excess glucose still accumulating in the blood is then taken and some of it is stored as glycogen in the liver and muscles, but this is not a lot, the amount would not even give you enough energy to see you through one active day.

The majority of it is stored as fat, in the adipose or fatty tissues. A major effect of too much insulin in the bloodstream is that it prevents you from burning fat, high levels of insulin suppress two important hormones called glucagons and growth hormones that are responsible for burning fat and sugar and promoting muscle development, respectively. So insulin in effect promotes fat storage and then also wards off the body’s ability to lose that fat!

Insulin which is stimulated by eating excess carbohydrates is largely responsible for all those bulging stomachs and fat rolls in thighs and chins that are so common in many people these days.

When insulin levels are high, lots of cell glucose channels become open which results in the blood sugar level then dropping too low. During insulin resistance the cell membranes have difficulty recognising insulin and too few channels are then opened. Therefore both insulin and glucose remain high in the blood and some cells will be deficient in glucose.

When our cells are exposed to insulin they get a little bit more resistant to it each time, so to compensate for this the pancreas just puts out more insulin to make up for it, but eventually even this will not help to store the excess sugar in the blood. Cells become insulin resistant because they are trying to protect themselves from the toxic effects of high insulin. They down-regulate their receptor activity and number of receptors so that they don’t have to be subjected to all that stimuli all the time.

High levels of insulin cause several problems for us, one of which is high blood pressure. It also causes sodium retention which in turn causes fluid retention and therefore leads to high blood pressure and congestive heart failure.

It also affects our metabolism as it can slow down our thyroid hormone conversion of T4 to T3. It affects how our muscles store sugar to burn for energy, when we burn sugar stored in our muscles before burning fat we get more muscle weakness and fatigue (which may explain what happens in chronic fatigue syndrome.)

A raised insulin level causes adrenalin to be secreted even if a person is not stressed, this can cause shakiness or tingling, pounding heart, perspiration, concentration problems which are all symptoms of reactive hypoglycaemia which can happen 2-3 hours after eating a carbohydrate meal.

It can also have a deteriorating effect on the endocrine system and cause hormonal imbalances

 Another of insulin’s roles is to assist with the storing of any excess nutrients, it plays a role in storing magnesium, but if our cells become resistant to insulin then we can’t store magnesium and gets excreted through our urine instead. Magnesium in our cells helps the muscles to relax but if we can’t store magnesium because the cells are resistant then we lose magnesium which makes the blood vessels constrict, affects our energy levels, and causes an increase in blood pressure.

The same thing applies to calcium, if calcium cannot get into the cells because they are resistant to insulin then it gets excreted in the urine or even worse gets dumped in places like the joints causing further problems.

Osteoporosis is another potential problem arising from insulin resistance. Insulin is a master hormone as it controls many other hormones such as growth hormone, testosterone and progesterone, and bone is built upon the command of such hormones. When these hormones are reduced the amount of bone building is reduced also and the amount of calcium excreted is increased.

Insulin increases cellular proliferation, which means that when we are talking about cancer that it will help cancer cells to grow. There are many studies that show that one of the strongest links to breast and colon cancers are the levels of insulin present.

Different cells respond to insulin differently. Some cells are more resistant than others, and some cells are incapable of becoming very resistant. The liver becomes resistant first, followed by the muscle tissue and lastly the fats. As all these major tissues become insulin resistant the pancreas will be putting more insulin out to compensate, but it can’t keep up with this high level of insulin production forever, once the production of insulin slows down as the pancreas is no longer functioning properly as it is exhausted, then the levels of blood sugar go up and the person becomes diabetic.

Type 2 diabetes occurs when the body no longer responds to insulin and as a result the levels of insulin in the blood become elevated over time and can raise the chances of kidney failure, blindness and heart disease.

When insulin resistance is found alongside other health problems such as diabetes, high blood pressure and heart attacks, it is called insulin resistance syndrome, or syndrome X.

High insulin levels are the biggest physical cause of accelerated ageing in man and insulin resistance is the basis for all of the chronic diseases associated with ageing – cardiovascular disease, osteoporosis, obesity, diabetes and cancer.

Fortunately insulin levels are very easily influenced by a healthy diet, along with exercise which helps to increase sensitivity to insulin. The diseases associated with insulin resistance are virtually non-existent in the primitive societies who still follow their traditional diets and have not adopted our westernised ways. Sugar and refined carbohydrates are the baddies here and need to be kept to a minimum to control the levels of insulin produced by the body.

I hope this has helped you to understand the role that insulin plays in the body and the importance of controlling its levels?