Tocotrienols are fat-soluble substances closely related to vitamin E. Like vitamin E, they have
, and help protect fatty substances in the body from being damaged by free radicals. In the 1990s, antioxidant supplements were thought to offer great potential for preventing a variety of diseases, including cancer and heart disease, and on this basis tocotrienols were offered on the market as healthful supplements. Tocotrienols have also been proposed for reducing cholesterol. However, subsequent studies have tended to pour cold water on all these hopes. At present, there is no reliable evidence that tocotrienols offer any meaningful health benefits.
Tocotrienols are not essential nutrients. They occur naturally in the oil extract of barley, palm fruit, rice bran, and wheat germ. Most commercially available supplements are made from rice bran oil or palm oil.
A typical recommended dose of tocotrienols is 200 mg daily.
open human trials
seemed to suggest that tocotrienols can correct
properly designed studies failed to find benefit.
Test-tube and animal studies, as well as one double-blind human trial have found promising hints that tocotrienols may help prevent cancer.
The double-blind study among these specifically found that tocotrienols might help prevent DNA damage, which could, in theory, help prevent many disease associated with aging, not just cancer.
However, none of this evidence rises above the level of "highly preliminary."
The hypothesis that tocotrienols can prevent heart disease simply by virtue of their antioxidant actions has lost favor, since the same hypothesis proved incorrect with
The bottom line: The health benefits of tocotrienols, if there are any, remain to be established.
Tocotrienols are thought to be safe substances. However, maximum safe doses have not been determined.
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Mustad VA, Smith CA, Ruey PP, et al. Supplementation with 3 compositionally different tocotrienol supplements does not improve cardiovascular disease risk factors in men and women with hypercholesterolemia.
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Mensink RP, van Houwelingen AC, Kromhout D, et al. A vitamin E concentrate rich in tocotrienols had no effect on serum lipids, lipoproteins, or platelet function in men with mildly elevated serum lipid concentrations.
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Ajuluchukwu JN, Okubadejo NU, Mabayoje M, et al. Comparative study of the effect of tocotrienols and -tocopherol on fasting serum lipid profiles in patients with mild hypercholesterolaemia: a preliminary report.
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2007 Sep 19. [Epub ahead of print]
Last reviewed December 2015 by EBSCO CAM Review Board
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