Why Antioxidants Are So Vital For Diabetes Sufferers

| April 17, 2012

One of the biggest advances in medical science in recent years has been the growing appreciation that ageing, chronic inflammation, obesity and diseases such as cancer, heart disease and diabetes all share a common cause. This is the phenomenon known as oxidative stress.

Normal biological functions naturally produce highly reactive molecules called free radicals, also called “reactive oxygen species”. These molecules have toxic or damaging effects in the body, which are counteracted by antioxidants that the body produces or that are present in foods. There is a constant war going on between the free radical “bad guys” and the antioxidant “good guys”. When there is insufficient antioxidant capacity to balance out the effects of the free radicals, the result is oxidative stress. Many scientists now believe that almost all of the disease processes in the body involve oxidative stress as a “final common pathway”.

The three ways oxidative stress makes diabetes worse

In diabetes, oxidative stress is involved in three main ways: damaging the insulin-producing beta-cells in the pancreas; contributing to insulin resistance; and causing changes to blood vessels that result in diabetic complications (heart disease, kidney damage and eye problems). It is also involved in obesity and high blood pressure, two conditions that frequently accompany diabetes.

High levels of blood sugar and blood fats cause oxidative stress in the pancreatic beta-cells, which produce insulin. The beta-cells are especially vulnerable to this kind of damage, which results in lowered output of insulin and increased cell death. This means that the pancreas cannot always produce sufficient insulin to deal with the level of sugar in the blood, leading to chronic high sugar levels which are in turn a cause of further oxidative stress. In this way a “vicious cycle” of damage to the pancreas is set up.

Oxidative stress also interferes with the way in which insulin acts in the body. Like other hormones, insulin provides chemical signals to cells to instruct them to act in particular ways. In the case of insulin, the instruction is to make changes to the cell membrane in order to allow glucose or fat to pass through into the cell. Oxidative stress changes the structure of specific proteins that are key to the way this insulin signalling system works. The outcome is that the cells no longer respond to insulin, a condition called insulin resistance and the underlying cause of type 2 diabetes.

The third way in which oxidative stress is relevant to diabetes is in causing many of the complications associated with it. Oxidative stress is a direct cause of vascular dysfunction, an abnormal condition of the blood vessels that leads in turn to plaque formation in the arteries and consequent risk of cardiovascular disease. It also damages blood vessels in the kidneys and eyes, causing diabetic nephropathy (kidney disease) and retinopathy (loss of vision).

To avoid oxidative stress and its damaging and degenerative effects, the balance between free radicals and antioxidants has to be loaded in favour of the “good guys”. This means eating foods and taking supplements that either provide antioxidants directly or stimulate the body to make its own. Top of the list is a compound called glutathione, which the body produces as its primary antioxidant. However, people with diabetes have low levels of glutathione because they are unable to manufacture enough of it.

Take these antioxidant supplements and eat a high-antioxidant diet

The raw materials for producing glutathione are the amino-acids cysteine, glutamic acid and glycine. Until recently, the best way to boost glutathione levels was to take a supplement of a form of cysteine called N-acetyl cysteine, or NAC. Glutathione could not be used directly as a supplement because it is very poorly absorbed by the digestive system and is rapidly broken down before it reaches the bloodstream. But now a new, stable form of glutathione has been developed, called S-acetyl-L-glutathione, and it is available as a supplement in the UK. I would advise anybody with diabetes to give it a try.

Vitamin C is another essential antioxidant that has been shown to both reduce the risk of developing diabetes and to reduce blood sugar and cholesterol levels in people with the condition. In a recent clinical trial, supplementing 1000 mg of vitamin C a day resulted in significantly lower fasting blood sugar and glycosylated haemoglobin (a measure of long-term blood sugar control) readings in people with diabetes who were also taking the medication metformin.

For vitamin C to work properly and to be recycled back into an active form after performing its antioxidant function, it needs another antioxidant, called alpha lipoic acid. This brilliant substance also protects your arteries, kidneys, nerves and eyes from the damage caused by too much sugar in the bloodstream. Clinical trials have shown clear benefits of taking additional alpha lipoic acid for people with type 1 and type 2 diabetes, particularly in treating diabetic neuropathy (nerve damage).

In my view, taking supplements of these major antioxidants provides a big benefit in the management of both type 1 and type 2 diabetes. In addition, it is important to get as much antioxidant benefit as possible from your food and drink, so make the following a regular part of your diet:

• Blueberries, cherries, raspberries and other “summer fruits”;
• Broccoli, kale, red cabbage and garlic;
• Kidney beans, lentils and chick peas;
• Walnuts, pecans and pistachio nuts;
• Apples, pears, oranges, grapefruit and plums;
• Dark chocolate (70 per cent cocoa solids or higher);
• Coffee, black and green tea;
• Red wine (in moderation!).

A diet that contains plenty of fruit and vegetables not only provides essential antioxidants, it also gives you plenty of fibre, which has its own benefits for people with diabetes. I shall be telling you more about that in my next blog post.

Wishing you the best of health,

Martin Hum
PhD DHD Nutritionist
for Real Diabetes Truth

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Bear in mind we are not addressing anyone’s personal situation and you should rely on this for informational purposes only. Please consult with your own physician before acting on any recommendations contained herein.


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