Inosine: Benefits, Side Effects, Dosage, and Interactions

In the multi-billion dollar supplement industry, workout enthusiasts turn to performance-enhancement products to change their body shape, energy level, and muscle girth. One ingredient found in such supplements is inosine, a nucleoside found in muscle tissue.

Brought to attention by Eastern sports scientists in the 1970s, athletes have since turned to inosine to improve their strength capabilities. Potential benefits of inosine stem from its acting as a building block for DNA and RNA, helping healthy nerve branches grow from nerves damaged in the brain and spinal cord.

It may also aid in the preservation of adenosine triphosphate (ATP), the main form of usable energy in your body. However, its actual clinical benefits are still being studied. Furthermore, by increasing uric acid levels inosine can precipitate kidney stones and gout.

Health Benefits

Inosine provides health benefits and can assist with serious health ailments, which include the following:

Treating Multiple Sclerosis

Data from a study published in the Journal of Alternative and Complementary Medicine suggest that inosine can raise serum urate levels, which could benefit multiple sclerosis patients. In a double-blind trial, researchers administered inosine orally throughout a year in 16 patients with remitting multiple sclerosis. They found inosine improved both serum urate levels and disability assessed by the Kurtzke Expanded Disability Status Scale. However, 4 of the first 11 patients treated with inosine developed kidney stones.

Treating Neurologic Injuries

In a review published in Cellular Physiology and Biochemistry, the authors concluded that inosine has potential as a safe, novel, multifunctional treatment for those suffering from the systemic complications a spinal cord injury can cause, and noted that clinical studies are ongoing.

Possible Side Effects

You might experience side effects by taking inosine, although no studies provide concrete information. These include the following:

• Weight gain. Anyone looking for dietary supplements with the goal of weight loss should avoid inosine. Manufacturers market products with this ingredient to help weight lifters gain muscle. 
• Elevated uric acid levels. Inosine increases uric acid levels, and can precipitate kidney stones and gout. You should closely monitor your intake of inosine to avoid such serious complications.

Dosage and Preparation

The recommended dosage for inosine is five to six grams daily, or 1,500 to 3,000 milligrams prior to training.

What to Look For

You should purchase inosine from a reputable organization because any level of contaminants can create a significant problem for your health. You also should look out for any inosine product that claims to "change the whole industry," doesn’t show its ingredients and alleges itself an appetite suppressant.

Other Questions

Should you include inosine as part of your dietary supplements to help your cardiovascular endurance?
The research suggests inosine doesn’t work for exercise enhancement in endurance sports, despite its involvement in ATP preservation. In a study published in Medicine and Science in Sports and Exercise, researchers found no cardiovascular improvements in runners taking inosine. In fact, they found inosine impairs performance.

Using nine trained endurance runners in a double-blind study, every participant received either an inosine supplement of six grams for two days or a placebo. Everyone then performed three exercises tests involving a warm-up, three-mile treadmill run, and a maximum treadmill run. Researchers measured VO2 maximum and metabolic markers such as glucose and uric acid levels. They found that the inosine group didn’t experience any improvements. In fact, the inosine group recorded a time to exhaustion faster than with the placebo group.

In addition, research shows inosine might not work for short-term aerobic performance either. In a study published in Medicine and Science in Sports and Exercise, researchers noted no significant difference when taking inosine versus not taking the supplement within a group of competitive male cyclists. Researchers had 10 competitive male cyclists complete a bike test following five days of either 5,000 milligrams daily of inosine or a placebo. Results showed no major changes in peak power, end power, fatigue index, total work completed, body mass and post-test lactate levels between the inosine and placebo groups. Once again, the time to fatigue was actually longer for the placebo group than with the cyclists who consumed inosine. Meaning, inosine inhibited performance.

Should you include inosine as part of your dietary supplements to improve weightlifting?
Inosine might help with your weightlifting efforts. A 1993 study from the Romanian Journal of Physiology: Physiological Sciences showed that inosine can offer muscle-building potential. Researchers split 14 top weightlifters into two groups: one group received 1.5 grams of inosine for six weeks and the other group received a placebo. They found inosine evoked muscular potential and an increase in serum lipids. Some of these changes lasted three weeks after the weightlifters stopped taking the supplement. However, this study is quite old and the number of study participants was quite small. More clinical studies are needed to determine if inosine can sufficiently work for weightlifters.