Animal study: octacosanol is an endurance sports supplement

Octacosanol is found in wheat germ oil, but far higher concentrations of the substance are to be found in sports supplements. The ergogenic effect of the compound was demonstrated in studies done decades ago, but there's a more recent Korean study that confirms this – and shows exactly how octacosanol works.

The chemical structure of octacosanol [shown here] is simple: it's a long chain of carbon atoms with a hydroxyl group at the one end. Octacosanol and its chemical relatives are often found on the outside of fruit, grains and leafy vegetables. They form Octacosanol the waxy layer that protects plants from the outside world.

In 1972 the swimming champion and sports scientist Thomas Kirk Cureton [who died in 1992] [nytimes.com 1992/12/24] published The Physiological Effects of Wheat Germ Oil on Humans in Exercise, in which he described the performance-enhancing effects of wheat germ oil on athletes. They gained more stamina, and the muscles in their lower arms and upper body gained strength.

Scientists first thought that these effects were due to the vitamin E analogues in wheat germ oil. But when they tested one of these – alpha tocopherol – on athletes and got disappointing results, mainstream science wrote wheat germ oil off. That might have been a too hasty reaction: later studies have shown that it's not vitamin E, but the aliphatic alcohols like octacosanol that improve athletes' performance.

Nutritionists at Yonsei University in Seoul, South Korea, set up this animal study to see whether there is a good reason for athletes to use supplements containing concentrated octacosanol. By the way, the Korean ministry of agriculture financed the study.

The researchers gave a group of rats a diet that contained 0.75 percent octacosanol [EO] for four weeks. A control group got feed with no additives [EC]. The researchers got the animals in both groups to run in a treadmill five times a week for the length of the experiment. The training programme is shown below. A second control group was given no exercise and no octacosanol either [SC]. At the end of the four weeks the researchers made the rats run to the point of exhaustion. As the figure below shows, the octacosanol supplement enhanced the endurance capacity by a factor of 1.8.