In Part 1 of this 4-part series, we discovered that symptoms of aging are linked to two main causes: cell division – the more rapidly cells divide, the more rapidly they age – and accumulated damage to cells. Continuing our exploration of conditions that trigger these two causes, this article looks at insulin mismanagement.
Insulin’s main role has long been perceived as storage of excess nutrients. However a second role is now being recognized, that of lifespan regulator with insulin often credited as being a major accelerant of aging. This stems partially from the one “lifespan marker” common to various studies of centenarians: insulin sensitivity.
This is hardly surprising when you consider how powerful insulin is. It influences other hormones, such as lowering the muscle-developing GH and the catabolic glucagon. It affects many bodily systems, such as cholesterol and triglyceride manufacture, and stimulation of the sympathetic nervous system (the resultant arterial spasm explains why heart attacks are 2-3 times more likely to occur after a high-carb meal). Its effects on aging cannot be overemphasized.
Let’s look at two of the reasons for this: insulin resistance and cell division.
As a mytogenic hormone, insulin causes cell proliferation and division, leading to one of the major diseases of aging: cancer. Studies have confirmed a strong correlation between cell division and breast and colon cancer, for example.
Cornering 22.8% of mortalities, cancer is one of the top three conventional causes of death in industrialized countries, according to the National Vital Statistics Report (October 2004), from the U.S. Department of Health & Human Services. However, although the most common cause is cardiovascular disease, if we look only at deaths under the age of 85, cancer takes the lead.
Excess insulin further accelerates aging through its promotion of insulin resistance.
Cells develop insulin resistance to protect themselves from the toxic effects of high levels of insulin. Insulin resistance starts with liver and muscle cells and means these cells are less able to accept insulin and sugar, forcing sugar to fat cells and so increasing body fat. (Forty percent of dietary carbs are converted to fat in a normal person; this percentage is expected to be much higher for someone who is insulin resistant.) When fat cells themselves become resistant, blood sugar levels elevate, prompting the pancreas to counter with increased insulin production. This is known as hyperinsulinemia. Insulin resistance and hyperinsulinemia are associated with Syndrome X and diabetes.
Insulin resistance has far-reaching health repercussions. Consider for example the vicious circle of magnesium deficiency and insulin resistance. Magnesium is necessary for the production and performance of insulin and so every rise in insulin depletes the body’s magnesium. However, insulin resistance blocks the storage of magnesium while at the same time causing hyperinsulinemia, and so magnesium demands increase as supplies dwindle. Over time, we become deficient in magnesium, which only serves to increase insulin resistance -- magnesium relaxes muscles and its deficiency constricts blood vessels, impeding glucose and insulin from reaching tissues and compounding insulin resistance.
The increased blood pressure as a result of low magnesium levels also raises the risk of heart disease. And since intracellular magnesium is essential for all energy-producing reactions in cells, magnesium deficiency reduces energy.
Looking for Signs
How can you tell if you are insulin resistant? Aside from the fact that it is very prevalent and increases with age and every exposure to insulin, insulin resistance has the following tangible effects: it makes people feel tired: it provokes brain fog that inhibits concentration, memory and creativity; it causes sugar or caffeine cravings; it elevates body fat; it increases blood pressure – hypertensive people are routinely insulin resistant; and it triggers depression as a result of the natural “downer” effect of carbs.
As a final interesting note about insulin resistance: some researchers believe determination of insulin resistance begins at the point of fetal fertilization. And that furthermore, if a pregnant woman has a high-carb diet, she increases the insulin resistance of her fetus, particularly if a female.
To learn how oxidation and glycation develop and how they contribute to aging diseases, please stay tuned for Part 3 of our anti-aging series.
Anna Kukhta specialises in peri-menopausal lifestyle and fitness training. She is located in London, England, and is contactable through Bernhardt@Amarantos-Fitness.com . She is presently completing her level 2 PICP certification.