Ribose

Ribose is a carbohydrate vital for the bodys manufacture of ATP, which is the major source of energy used by our cells. Quite a few studies have been done on ribose, mostly relating to its potential usefulness for individuals with heart disease. When the heart is starved for oxygen, as can occur with a heart attack or angina, it loses much of its ATP, and its ATP levels remain low for several days, even after blood flow is resumed. Scientists have found that supplying extra ribose in the blood helps restore the hearts normal ATP levels more quickly. This may therefore mean that ribose supplements can improve heart functioning and increase exercise capacity, but these benefits have not yet been proven. Ribose has also been tried for improving exercise capacity in individuals with certain enzyme deficiencies and other rare conditions that cause muscle pain during exertion. There is weak evidence that it may help people with some of these conditions—but not others—to exercise without pain. Finally, ribose has recently been touted as an important new performance enhancer for athletes. However, there is as yet no evidence at all that it works in this capacity.

Ribose is not an essential nutrient. Although it is a common sugar present in the bodies of animals and plants, food sources dont supply recommended dosages.

The dose of ribose that will improve sports performance in ordinary athletes has not been determined. Typical doses recommended by sports supplement manufacturers are 1 to 10 g per day. Participants in a study of heart disease took 60 g of ribose in water (15 mg, 4 times a day) by mouth for 3 days. In case reports, people with rare enzyme deficiencies reported benefit with oral doses of 3 to 4 g taken every 10 to 30 minutes during exercise, sometimes totaling 50 to 60 g per day. Warning: If you have either of these conditions, take ribose only under the supervision of a doctor. Typically provided as a powder to be dissolved in water or in liquid form, ribose is also available commercially in capsules. The dissolved powder has a sweetish taste that some people find unpleasant.

Ribose may be of benefit in improving exercise tolerance in people with severe coronary artery disease by helping the heart regenerate its ATP, but the evidence as yet is highly preliminary. Sports enthusiasts are more interested in ATPs effects on regular muscles than on the heart muscle. At least one animal study seems to show that skeletal muscle, like heart muscle, replenishes ATP more quickly when ribose is added to the blood. However, a small double-blind trial in humans failed to find any evidence of enhanced muscular performance or any increase in the ability of muscles to synthesize ATP. In a few case reports, ribose has increased exercise ability in people with a rare condition involving deficiency of the enzyme myoadenylate deaminase (AMPD). However, no double-blind studies of ribose in AMPD deficiency have been conducted. Small double-blind studies have failed to find ribose effective for another rare enzyme deficiency called McArdles disease, and for Duchennes muscular dystrophy.

Coronary Artery Disease Individuals with sufficiently severe coronary artery disease suffer reduced blood flow to the heart (ischemia) with exercise, and experience angina pain. One small study examined whether giving ribose can improve exercise tolerance for people with coronary artery disease. In the study, 20 men with severe coronary artery disease walked on a treadmill while researchers noted how long it took for signs of ischemia to develop. For the next 3 days, the men took either oral ribose (60 mg per day) or placebo, after which they repeated the treadmill test. Results of the final test showed that those taking ribose increased the time they were able to walk before developing EKG signs of ischemia, while those taking placebo had no such improvement. This preliminary study was too small to prove anything, but it certainly suggests that further investigation would be worthwhile.

There are no reports of lasting or damaging side effects from ribose, but formal safety studies have not yet been conducted. Reported minor side effects include diarrhea, gastrointestinal discomfort, nausea, headache, and hypoglycemia.