D-Ribose

D-ribose (referred to as ribose in this article) is a type of sugar made with five carbon atoms known as a pentose.^[10][11] Ribose forms the backbone of RNA, the genetic material involved in translating genes into protein.^[10][11] Ribose is also a component of molecules involved in energy metabolism, including ATP, coenzymes such as nicotinamide adenine dinucleotide hydride (NADH), and vitamins such as niacin (vitamin B3) and riboflavin (vitamin B2).^[10][12][11]

Ribose is naturally produced in the body via the pentose phosphate pathway,^[10][12][13] but small amounts can also be obtained from the diet, because it is found in meats, vegetables, and soy-containing products.^[14][15][16] Ribose is also sold as a dietary supplement, marketed to enhance energy levels and recovery in athletes.^[15]

Potential benefits for heart health

Several review papers claim that ribose can treat heart failure in people with coronary artery disease;^{[17][18][19][20]} however, much of the evidence comes from preclinical studies in rodents.^{[21][22][23][24]} That said, some randomized controlled trials (RCTs) have found that supplementation with ribose (in addition to heart failure medications) can improve the symptoms of heart failure,^[1][2][3] including increased left ventricular ejection fraction and exercise capacity, both of which are impaired in people with this condition.

Despite these possible benefits in heart failure, there are few clinical studies, outcomes are variable between studies, and potential risks need to be examined in more detail (see What are ribose’s main drawbacks?). Therefore, well-designed large-scale RCTs are needed to understand ribose’s efficacy in people with heart failure before it can be considered for widespread clinical practice.

Potential benefit for exercise recovery

Some RCTs show that supplementation with D-ribose can reduce feelings of muscle soreness and markers of muscle damage and oxidative stress following exercise,^[5][6] while increasing the resynthesis of ATP in skeletal muscle.^[7] However, the recovery of muscle strength is not improved,^[5] and other studies find mixed outcomes or that ribose has no benefit on recovery.^[8][9][25] Furthermore, RCTs have found that ribose has no benefit on exercise performance during either aerobic^[26] or anaerobic^{[27][7][28][29][9]} exercise tests. Therefore, ribose might assist with recovery, but it does not improve exercise performance. That said, studies in this field include fewer than 10 participants and only include men, which highlights the need for higher-quality research.

Although some studies report minor side effects following ribose ingestion, such as nausea and diarrhea,^{[30][31][15][4]} regulatory bodies like the European Food Safety Authority (EFSA) state that ribose is generally considered safe for consumption at a daily intake level of up to 36 milligrams per kilogram of body weight.^[31][15][4] This is equivalent to approximately 2.5 grams per day in a person weighing 70 kg (154 pounds).

One drawback emerges from research showing that ribose can react with proteins in the body via process called glycation, leading to the formation of endogenous advanced glycation end products (AGEs),^[32][33][34] molecules that can damage cells and cause health complications. Furthermore, evidence from preclinical studies in rodents shows that high doses of ribose can cause cognitive decline,^[35] possibly via the accumulation of AGEs.^[35][34] These findings raise an important question concerning the potential adverse effects of long-term ribose supplementation. This concern is further emphasized by the lack of thorough dose-response and pharmacokinetics studies in humans. A full understanding of ribose’s safety profile in humans is lacking.

Another drawback is that the evidence underpinning the effects of ribose on heart failure and exercise performance and recovery (see What are ribose’s main benefits?) has a moderate to high risk of bias because there are few studies, small sample sizes, and a high level of between-study heterogeneity.

Ribose is used in the body to form RNA (the genetic material that helps translate genes into proteins)^[10][11] and molecules involved in energy metabolism, including ATP, nicotinamide adenine dinucleotide hydride (NADH), niacin (vitamin B3) and riboflavin (vitamin B2).^[10][12][11] These functional abilities to increase protein synthesis and energy metabolism might explain how some studies have found that supplementation with ribose can reduce symptoms of heart failure,^[1][2][3] increase the resynthesis of ATP in skeletal muscle following exercise,^[7] and reduce postexercise muscle soreness and muscle damage.^[5][6] See What are ribose’s main benefits? for more details.