Betaine Athletic Boost Not Linked to Nitric Oxide

March 23, 2011

Recent science suggests that betaine, a compound derived from beetroot and other vegetables, may increase muscle endurance in strength and resistance exercise; but new research suggests that betaine’s sports benefit is not definitely linked to nitric oxide.

Recent science suggests that betaine, a compound derived from beetroot and other vegetables, may increase muscle endurance in strength and resistance exercise; but new research suggests that betaine’s sports benefit is not definitively linked to nitric oxide.

Dietary supplements purporting to increase nitric oxide have soared in recent popularity for athletic use-based on the theory that nitric oxide increases blood flow and thereby nutrient delivery and exercise recovery. Regardless of whether or not such supplements have these effects, betaine does not-at least not in young, healthy males.

Researchers at the University of Memphis designed three studies on 8, 13, and 10 young, exercise-trained subjects. In the first study, subjects were assigned to acute betaine intake (1.25 and 5.0 g). In the second study, subjects were assigned to chronic betaine intake (2.5 g per day for 14 days). A final third study looked at chronic intake, followed by acute intake (6 g for 7 days, then one dose of 6 g). Periodic blood sampling measured plasma nitrate/nitrite as an indicator of nitric oxide levels.

In each study, researchers could not detect any statistically-significant increases in nitrate/nitrite levels. But the study’s author claims such findings conflict previous studies, which found betaine to increase those levels in older men.

“Acute or chronic ingestion of betaine by healthy, exercise-trained men does not impact

plasma nitrate/nitrite,” wrote the study’s author. “It is possible that betaine supplementation by older and/or de-conditioned individuals, or possibly by women, may result in elevated nitrate/nitrite levels in plasma.”

As for betaine’s athletic boost in young, exercise-trained men, it appears that some mechanism outside of nitric oxide is at play.

BetaPower betaine was supplied by Danisco (Copenhagen) for the study, which was funded by Danisco and the University of Memphis. The study was published online at the Journal of the International Society of Sports Nutrition.