Will avoiding dietary sugar prolong life?

Nobody has yet shown any way to extend the life span of humans. However, both exercise and calorie restriction (with adequate nutrients) have been shown to extend the life span of animals. Both of these measures apparently extend life by increasing the number and size of mitochondria in cells and making them turn food into energy more efficiently. Each cell in your body contains up to several hundred mitochondria which provide the most efficient chemical reactions in your body for converting food into energy.

An exciting new study on worms offers a potential method for you to prolong life and good health. When blood sugar levels rise too high, sugar enters cells in large amounts. An earlier study showed that adding sugar to the diet of the worm, C. Elegans, shortens its life (Cell Metabolism, October 2007). Now the researchers have found that preventing sugar from entering cells by altering the genes for DAF-2, DAF-16 and Heat Shock Factor-1 causes the same changes as avoiding sugar and extends the worms' life span up to 20 percent (Cell Metabolism, November 2009). These benefits could also occur in humans because we have the same three genes that control sugar entry into cells as those of the worms.

Calorie restriction and exercise probably prolong life by the same mechanism: they enlarge and activate mitochondria in cells that turn food to energy. This helps mitochondria to clear free radicals much more rapidly from the body. Free radicals can damage cells and therefore shorten life. The worms' cells responded to the absence of sugar inside cells by increasing their ability to clear free radicals from their bodies which prolonged their lives. Indeed, when sugar was allowed to again enter their cells, they still could clear free radicals faster and live longer because their enlarged mitochondria were more efficient in removing free radicals.

This research on worms questions the way doctors treat type II diabetes when they prescribe drugs to lower blood sugar levels by driving sugar into cells. The best treatment may be to develop diets and drugs that prevent blood sugar from entering cells in the first place.

For now, we know that you will shorten your life and increase risk for many diseases by allowing blood sugar levels to rise too high after meals. A diet that keeps sugar from rising too high after meals (and reduces the entry of sugar into cells) can prevent diabetes, help control all the side effects of diabetes (JAMA, December 16, 2008), cause the most weight loss, and allow many type II diabetics to safely stop their medications (Nutrition and Metabolism, January 2009). Avoid foods that cause the highest rise in blood sugar levels: sugar in liquid form (sugared drinks, fruit juices, and adding sugar to any drink); foods made from flour (bread, spaghetti, macaroni, pretzels, bagels and so forth); and foods with added sugar.

You should also exercise every day. Exercise causes muscles to remove sugar from the bloodstream at a very rapid rate and this effect lasts maximally for about half hour after you stop exercising, then tapers off until it stops completely after about 17 hours. Furthermore, since lack of vitamin D causes high blood sugar levels, you should make sure that your blood level of vitamin D3 is above 75 nmol/L. New vitamin D recommendations