The vitamin E family consists of four tocopherols and four tocotrienols each designated as alpha, beta, gamma, or delta based upon slight differences in attached molecules. Of these naturally occurring vitamin E compounds, alpha-tocopherol (alpha T) has emerged has the most potent of these compounds in terms of vitamin E activity. However, newer information indicates that for other activities including antioxidant, cholesterol lowering, and anti-cancer effects that the tocotrienols (T3s), especially delta-tocotrienol (delta T3) exert more profound effects.1 So, while in terms of vitamin E activity the order of potency would be:
alpha T > beta T > gamma T > alpha T3 > delta T > gamma T3 > delta T3
The order of potency for acting as an antioxidant, cholesterol-lowering agent, and in cancer prevention may be just the opposite:
delta T3 > gamma T3 > delta T > gamma T > alpha T3 > beta T > alpha T
What is the difference between a tocopherol and a tocotrienol?
The difference is that the tocotrienol has 3 double bonds within the main body of the molecule. Just like as in polyunsaturated oils, the presence of these double bonds give the tocotrienols greater fluidity and make it much easier for the body to incorporate them into cell membranes, especially delta-tocotrienol.2 Differences between the various individual members of the tocopherol and tocotrienol family are due to different molecules found at the R1, R2, and R3 positions.
What are the health benefits of tocotrienols?
In comparing the health benefits of the tocopherols vs. the tocotrienols I will limit the discussion to the following areas: antioxidant effects, anticancer effects, cholesterol lowering effects, and effects on other aspects of cardiovascular disease. Do not misunderstand me. I am NOT saying that vitamin E (alpha-tocopherol) is not important. It possesses the greatest physiological vitamin E activity and is an important component of any nutritional supplementation plan. However, when some specific or additional support is needed then the tocotrienols, especially delta-tocotrienol, appears to offer even greater benefit.
While vitamin E is generally regarded as the most important fat-soluble antioxidant, alpha-tocotrienol has been shown to be 40 to 60 times more potent than alpha-tocopherol in the prevention of lipid peroxidation. Even more potent is delta-tocotrienol - by far the most powerful antioxidant of the entire vitamin E family. Tocotrienols may prove more valuable in protecting the interior cell membranes, such as those that surround the cell nucleus and mitochondria, because of their greater ease in being incorporated into cellular membranes.1,2
Tocopherols have virtually no cholesterol-lowering activity, but numerous clinical studies have shown tocotrienols, specifically gamma-tocotrienol and delta-tocotrienol, to inhibit the manufacture of cholesterol within the liver.3 Specifically, these tocotrienols inhibit the liver enzyme HMG-CoA reductase - the same enzyme inhibited by the statin drugs and red yeast rice. Although clinical studies have yielded inconsistent results with tocotrienol preparations in lowering cholesterol, that is easily explained by taking a closer look at the types of tocotrienols used in the study and their dosage.
Commercial sources of tocotrienols
There are three commercial sources of tocotrienols - rice bran oil, palm oil, and annatto bean (DeltaGOLD™). It is important to understand the shortcomings of the first two to truly appreciate the differences in the results achieved in the clinical trials on lowering cholesterol.
Ratios of tocopherols and tocotrienols in commercial sources
There are a couple of very important points to make when looking at the results:
When these factors are taken into consideration it is easy to explain why certain studies were positive and others were negative.1,5-9 Tocotrienol concentrates with higher amounts of gamma- and delta-tocotrienols, and lower alpha-tocopherol have produced reductions of total cholesterol of 15% and an 8% reduction in LDL levels within the first four weeks of use.
Additional cardiovascular benefits
Tocotrienols have been shown to exert additional benefits to the cardiovascular system including an ability to decrease in the amount of cholesterol plaque in arteries, lower the level of the extremely damaging lipoprotein (a), prevent the aggregation of platelets, and inhibit the expression of cellular adhesion molecules.1,10 All of these factors are extremely important in the development and progression of atherosclerotic plaque. Delta-tocotrienol has been shown to be the most active of the tocotrienols.
Summary of benefits of delta-tocotrienol
Anticancer effects of tocotrienols
The anticancer effects of tocotrienols have garnered a lot of attention. In addition to their important antioxidant effects, several other mechanisms have been proposed. For example, one of the innate protectors against cancer is a process known as "apoptosis." Basically, apoptosis is an encoded suicide program designed to protect cells from becoming cancerous. When this process does not work cancer develops. Tocotrienols are effective promoters of apoptosis with delta-tocotrienol being twice as potent as gamma-tocotrienol.11 Another anticancer mechanism involves inhibiting enzymes within cancer cells that stimulate them to replicate. Gamma-tocotrienols was shown to be three times more potent in inhibiting growth of human breast cancer cultured cells than chemotherapy drug tamoxifen.12
What are the dosage, drug interactions, and safety information
Tocotrienols are extremely safe and no side effects have been reported.13 Given the effects on platelet aggregation, you will need to inform your physician of their use if you are going in for surgery, or taking the blood thinning drug Coumadin® (warfarin) or anti-platelet drugs like Ticlid® (ticlopidine).
Tocotrienols enhance the cholesterol-lowering effects of statin drugs and, presumably, red yeast rice extract.7
Michael T. Murray, N.D., is widely regarded as one of world's leading authorities on natural medicine. A prolific author, Dr. Murray has written over 20 books on health and nutrition including the best-selling Encyclopedia of Natural Medicine and his latest book The Encyclopedia of Healing Foods. Dr. Murray is also Director of Product Development and Education for Natural Factors one of the leading manufacturers of natural products.