Insulin’s job is to take sugar out of the bloodstream and feed it to the cells which use the sugar as fuel. When there is more sugar in the bloodstream than can be actively used immediately, the sugar is stored as fat for future use in case of starvation. Insulin also stores protein in muscle cells, so it can be considered an anabolic hormone. And insulin stores magnesium, an important mineral that aids in keeping blood vessels dilated and muscles relaxed. The bad news is that chronic problems with insulin have DEVASTATING effects on our health, but the good news is that insulin is one of the easiest hormones for us to control. We have all kinds of hormones that raise blood sugar - cortisol, glucagon, epinephrine, aldesterone etc., but insulin is the ONLY hormone that lowers blood sugar, so our body has no back-up system if insulin stops working. Why would that be, do you think? Does it not strike you as odd that in the fabulous system that is our body there is no back-up system for insulin, when our body tends to have all kinds of fall-back plans if something should fail?
Perhaps it is worth looking at the question through the eyes of primitive humankind. Not having lived at that time I can’t be certain, but I would imagine that there would have been times of limited food, and being able to increase blood sugar levels would have been critically important in order to fuel the body when there was very little or no food being consumed. Just like many other animals, in the spring and summer when fruit, plants and grains were available, it was advantageous to have insulin store some fat to aid chances of survival through the lean winter months. Fruit would be dried, and other foods
fermented, but especially in the colder climates, people would rely on wild animals or fish for most of their food in the winter. Meat and fat do not induce a big insulin response. So, perhaps in the body’s wisdom, it did not think it needed more than one method to lower blood sugar,as high carbohydrate (plant food) diets simply did not happen day in day out all year round except possibly in tropical climates. I think it is very interesting to note that Weston A. Price, who traveled the world examining the diets of primitive cultures before they came in contact with "white man’s food", found NO vegetarian peoples, even in the tropics. All the cultures he studied had no signs of the chronic diseases that plague our society, (even those that ate extremely high fat diets!) had excellent bone structure, and very few cavities.
Fast forward to today’s world, a blink of the eye in evolutionary time, and suddenly, even in colder climates, we have access to carbohydrate (another word for sugar) all year round in huge quantities, much of it highly processed and far sweeter than would have been consumed in primitive times. We are being told that eating large amounts of grains in the form of breads and cereals is healthy, and practically every processed food in the supermarket has some form of sugar in it - no wonder our insulin is having trouble coping! It was never meant to deal with this amount of sugar! On top of that, we are told to eat low fat, so there is frequently nothing to slow the sugar into the bloodstream, which makes insulin’s job even harder. When genetically one’s body is built to handle relatively few carbohydrates, and instead we are eating far more than our body can handle, it is no surprise that disease is a result. The Inuit are a perfect example. Having moved away from their traditional diet high in seal blubber, salmon, sea weeds, and cranberries when in season, to a diet high in processed carbohydrate all year round, they are currently dealing with rampant type 2 diabetes. Biochemical individuality plays a huge role in how well our bodies can cope with carbohydrates.
Eating large amounts of high glycemic foods (foods that turn into sugar in the body quickly) is problematic on many fronts. High blood sugar causes large amounts of insulin to be secreted into the blood, and insulin is very hard on the arteries, damaging them, and causing the body to call on cholesterol to try and fix the problem. High insulin levels also increase blood pressure by increasing sodium retention and increasing sympathetic tone. High insulin decreases T3 production affecting the job of the thyroid, suppresses glucagon and growth hormone levels, and decreases DHEA levels, which in turn decreases progesterone and testosterone levels. If insulin levels are chronically high, the body starts ignoring insulin, down-regulating the receptors on the cell surfaces, and now, because insulin is no longer working, blood sugar levels are also too high (insulin resistance or pre-diabetes). High blood sugar also damages arterial walls through glycation creating Advanced Glycation Endproducts increasing arterial inflammation, and once again, cholesterol is summoned to repair the damaged arteries. Frequently the sugar in the blood glycates with cholesterol, making the situation worse. This is how type 2 diabetes and heart disease are linked.
So, insulin has a direct affect on the thyroid hormones, and the sex hormones. Guess what hormone has a direct affect on insulin? You guessed it - cortisol. Cortisol decreases insulin secretion as well as insulin sensitivity, which is logical, because if you are stressed, it is not helpful to have insulin remove the sugar that you need to help you fight or run! So, if the reason you are stressed is you are sitting in a traffic jam, that increased blood sugar is not being used - it is just damaging your arteries. This is another way stress causes heart disease. As far as I can tell so far, cortisol is the kingpin hormone. I have found no other hormone yet that suppresses cortisol. If I find one, you will be the first to know! So, decreasing stress levels in order to control cortisol will have the biggest impact on our health, and lowering insulin levels is not far behind!
There are two ways to lower insulin levels:
1) Avoid eating foods that cause a large insulin response, like all products that contain any form of sugar, flour products, starchy below-ground vegetables, and fruit juice. Avoid all processed food. If you are insulin resistant, pre-diabetic or already have type 2 diabetes or heart disease, it may also be a good idea to limit whole grains and fruit for the time being, and eat lots and lots of above-ground, colourful veggies and sea vegetables as your carbohydrate source. Make sure that you add a little quality fat (butter, ghee, olive oil) to your veggies so you can absorb the vitamins and minerals in them.
2) Exercise uses up the sugar in the blood stream so it does not get stored as fat. Resistance exercise or weight training is particularly useful, as it increases insulin-receptor sensitivity. If you set up your weight-training program in a circuit format and move quickly between exercises you will keep your heart-rate up as well, so additional cardiovascular exercise is unnecessary.
Sugar, the disease generator
How hormones, neurotransmitters and steroids work
Type 1 diabetes - a new discovery
Another “healthy heart guide” that got it wrong
Cortisol, our stress hormone
Stress and cardiovascular disease
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Copyright 2007 Vreni Gurd