Effects of oral D-ribose supplementation on anaerobic capacity and selected metabolic markers in healthy males.
Kreider RB. Int J Sport Nutrition Exerc Metab. 2003.
Oral D-ribose supplementation has been reported to increase adenine nucleotide synthesis and exercise capacity in certain clinical populations. Theoretically, increasing adenine nucleotide availability may enhance high intensity exercise capacity. This study evaluated the potential ergogenic value of D-ribose supplementation on repetitive high-intensity exercise capacity in 19 trained males. Subjects were familiarized to the testing protocol and performed two practice-testing trials before pre-supplementation testing. Each test involved warming up for 5 min on a cycle ergometer and then performing two 30-s Wingate anaerobic sprint tests on a computerized cycle ergometer separated by 3 min of rest recovery. In the pre- and post-supplementation trials, blood samples were obtained at rest, immediately following the first and second sprints, and following 5 min of recovery from exercise. Subjects were then matched according to body mass and anaerobic capacity and assigned to ingest, in a randomized and double blind manner, capsules containing either 5 g of a dextrose placebo or D-ribose twice daily (10 g/d) for 5 d. Subjects then performed post-supplementation tests on the 6th day. Our results indicate that oral ribose supplementation (10 g/d for 5 d) does not affect anaerobic exercise capacity or metabolic markers in trained subjects as evaluated in this study.

Effects of ribose supplementation on repeated sprint performance in men.
J Strength Cond Res. 2003.
After familiarization, subjects performed 2 bouts of repeated cycle sprint exercise (six 10-second sprints with 60-second rest periods between sprints) in a single day. After the second exercise, bout subjects ingested 32 g of ribose or cellulose (4 x 8-g doses) during the next 36 hours. After supplementation, subjects returned to the laboratory to perform a single bout of cycle sprinting (as described above). After a 5-day washout period, subjects repeated the protocol, receiving the opposite supplement treatment. Ribose supplementation lead to statistically significant increases in mean power and peak power in sprint 2 (10.9 and 6.6%, respectively) and higher (although not significant) absolute values in sprints 1, 3, and 4. In conclusion, ribose supplementation did not show reproducible increases in performance across all 6 sprints. Therefore, within the framework of this investigation, it appears that ribose supplementation does not have a consistent or substantial effect on anaerobic cycle sprinting.

No effects of oral ribose supplementation on repeated maximal exercise and de novo ATP resynthesis.
J Appl Physiol. 2001.
A double-blind randomized study was performed to evaluate the effect of oral ribose supplementation on repeated maximal exercise and ATP recovery after intermittent maximal muscle contractions. Muscle power output was measured during dynamic knee extensions with the right leg on an isokinetic dynamometer before (pretest) and after (posttest) a 6-day training period in conjunction with ribose (R, 4 doses/day at 4 g/dose) or placebo intake. Oral ribose supplementation with 4-gram doses four times a day does not beneficially impact on postexercise muscle ATP recovery and maximal intermittent exercise performance.

I am a health food store owner in Sacramento, CA. I saw an ad by a company called Valen Labs, Inc.. The claims were "Patented, all-natural Bioenergy Ribose has been clinically proven to dramatically speed energy recovery. Strenuous exercise, had work, and many clinical conditions rob cells of energy. Bioenergy Ribose restores energy needed to minimize fatigue and reduce pain, stiffness and cramping. What is your opinion on ribose?
   I personally have not seen any studies that confirm that using it is helpful for those who exercise. Perhaps Valen Labs is familiar with research on this topic that I am not aware of.

D-Ribose improves diastolic function and quality of life in congestive heart failure patients: a prospective feasibility study.
Eur J Heart Fail. 2003.
Patients with chronic coronary heart disease often suffer from congestive heart failure (CHF) despite multiple drug therapies. D-Ribose has been shown in animal models to improve cardiac energy metabolism and function following ischemia. This was a prospective, double blind, randomized, crossover design study, to assess the effect of oral D-ribose supplementation on cardiac hemodynamics and quality of life in 15 patients with chronic coronary artery disease and CHF. The study consisted of two treatment periods of 3 weeks, during which either oral D-ribose or placebo was administered followed by a 1-week wash out period, and then administration of the other supplement. Assessment of myocardial functional parameters by echocardiography, quality of life using the SF-36 questionnaire and functional capacity using cycle ergometer testing was performed. The administration of D-ribose resulted in an enhancement of atrial contribution to left ventricular filling, a smaller left atrial dimension and a shortened E wave deceleration by echocardiography. Further, D-ribose also demonstrated a significant improvement of the patient's quality of life. In comparison, placebo did not result in any significant echocardiographic changes or in quality of life. This feasibility study in patients with coronary artery disease in CHF revealed the beneficial effects of D-ribose by improving diastolic functional parameters and enhancing quality of life.

How safe would D-ribose be for someone with atrial fibrillation?
   I have not seen any studies testing the influence of this sugar supplement on atrial fibrillation so I don't know at this time.

Fatigue and fibromyalgia
The use of D-ribose in chronic fatigue syndrome and fibromyalgia: a pilot study.
J Altern Complement Medicine. 2006. Teitelbaum JE, Johnson C, St Cyr J. Fibromyalgia and Fatigue Centers, Dallas, TX, USA.
This open-label uncontrolled pilot study was done to evaluate if D-ribose could improve symptoms in fibromyalgia and/or chronic fatigue syndrome patients. Forty-one patients with a diagnosis of fibromyalgia and/or chronic fatigue syndrome were given D-ribose at a dose of 5 grams three times a day for a total of 280 g.  D-ribose supplements improved all five visual analog scale categories: energy; sleep; mental clarity; pain intensity; and well-being, as well as an improvement in patients' global assessment. Approximately 66% of patients experienced significant improvement.

I suffer from fibromyalgia and recently read an article stating that ribose can "cure" it. Have you any information indicating that ribose cures fibromyalgia or that if not a "cure" can at least be helpful?
   I have seen one small study that showed a benefit.

How is this sugar supplement available?
Ribose supplements are available as a pill, liquid or powder. For the time being I don't see any major advantages of one form over another.

Ribose side effects, testimonial
My daughter and I took D-Ribose for help with chronic fatigue. It seemed to help, but at a doctor's appointment which took place one month after starting to use D-Ribose both of our blood pressure readings were 150/100 each three reading attempts. D-Ribose was the only change to our supplements and we discontinued using it. After discontinuing, I realized I had been cognitively hazy while using it, which I did not notice since I was congnitively hazy while using it. Two months later, at another doctor's appointment, my blood pressure was back to my usual 120/70. My daughter's blood pressure also returned to normal. The dosage we were using was at most a quarter of the recommended dose. I read up on D-Ribose before using it and found no references to any serious side effects. After the high BP experience, I dug deep into forums and found many people reporting an intolerance to it. None of them had any testing done while trying it. The only clinical reference to negative reactions I could find was by a Dr. Cheney who reported that a third of his CFS patients could not tolerate using D-Ribose. I downloaded the FDA approval for D-Ribose. All of the human studies done on D-Ribose were very short, as in a few weeks. Animal studies were much longer, of course. None of the studies mentioned taking blood pressure readings, though only the study abstracts were contained in the FDA approval document. I cannot find any evidence that any study has examined negative side effects of D-Ribose. I think a BP elevation of 30 points is very significant, am certain it was due to the use of D-Ribose in my case, and hope you will include this ancedote on your website.
   A. To confirm the relation to high blood pressue it would be interesting to repeat usage to see if it occurs again.

Questions
Does taking D ribose supplement have any negative effect on type 2 diabetes?
    I suspect low amounts would not have much of an impact, but, as of 2012, I have not come across any human trials with ribose supplements in those who have diabetes.

Why would i take a multivitamin for energy when ribose is available?
    There are many, many ways the human body produces energy, not just with ribose. You may ask why eat all kinds of different foods since bread alone can give calories.

Through my personal research and experience, I have found great relief with the use of d-ribose. Increased energy and reduced procrastination was a very pleasant effect for over a year. I began the regime (skeptically) with the recommended 3 tsps per day (1 tsp 3x per day) for 3 weeks, reducing it to 2 tsps for 3 weeks and finally to 1 tsp per day. This included the 6 days on, one day off for the entire time. Now, more than a year later, even one teaspoon once a week causes cardiac discomfort. My heart pounds like it wants to pop out of my chest. It appears that the highest dose I could risk is about a quarter tsp per week. Have you come across such a reaction in your experiences? Would you be able to cite any research which might help alleviate this reaction? I am currently 54 and I take many other supplements also. I have tried eliminating all supplements and only taking d-ribose over the course of a month with these reactions. Also, as a side note, I have a similar reaction with vitamin E. I can only tolerate about 50 IU per week, so I've removed it from my regime, many years ago.
    I don't have enough experience with use of daily d ribose supplement intake to know whether it causes cardiac issues. I have not had any previous reports from users that indicate cardiac problems. There are many supplements that can cause heart rhythm disturbances or increased heart rate.