The Little-Known Benefits Of TocotrienolsAugust 2014
By Thomas Rosenthal
If your vitamin E supplement contains only tocopherol forms, you may not be getting all of the benefits this nutrient has to offer. While tocopherols are very important, they lack many of the synergistic benefits offered by their cousins, the tocotrienols.
Few people realize that vitamin E is composed of eight different compounds. Half of these are called tocopherols, which is the most common form of vitamin E. The other half are known as tocotrienols.
Scientists are discovering that tocotrienols provide valuable therapeutic and preventive options for the diseases of aging that tocopherols alone may not provide.
For example, researchers found that tocotrienols given to mice with pancreatic cancer significantly improved their survival. Only 10% of animals in the control group survived for the study period while 70% of those taking tocotrienols survived!1 Pancreatic cancer is a particularly fast-moving and lethal form of cancer, and this study presents a promising new treatment option.
Beyond cancer, research is showing that tocotrienols have a place in reducing important risk factors for some of the most lethal chronic diseases. For example, tocotrienols have been found to promote new artery formation after a stroke, lower homocysteine levels, improve insulin sensitivity, protect vital brain circuitry, and even prevent bone loss.2-5
In addition, tocotrienols have powerful lipid-lowering, anticancer, and neuroprotective properties that tocopherols lack.6,7
These recent investigations into this overlooked form of vitamin E are providing new strategies to fend off multiple risk factors to ensure optimal health.
Tocotrienols And Cancer
For many years, studies of vitamin E produced inconsistent results regarding its effect on cancer. It is now thought that this inconsistency was likely due to the widespread use of alpha-tocopherol alone in such studies.8 We now know that alpha-tocopherol has weak anticancer activity, while tocotrienols are more potent cancer-preventive agents.8-10
In a recent finding that stunned researchers, tocotrienol supplementation was found to dramatically extend the life span of mice with pancreatic cancer.8 Pancreatic cancer is among the most aggressive and deadly human cancers, with survival times typically counted only in months.11,12 The 2013 study showed that after 16 weeks of treatment, just 10% of placebo-treated mice remained alive, while 30% survived in a group treated with gemcitabine, a standard chemotherapy drug. However, a remarkable 70% of mice had survived in the tocotrienol group. Combination treatment with gemcitabine and tocotrienols produced a remarkable 90% survival rate.1
Tocotrienols are the ultimate multi-targeting nutrient when it comes to cancer. Their actions affect virtually every step in the progression of cancer.13 They share antioxidant effects with tocopherols, but there seems to be a considerable amount of anticancer action that is unrelated to antioxidant actions.13,14
Proposed Mechanisms Of Tocotrienols In Cancer Prevention
Tocotrienols impact several factors that tumors need for their development and growth.
Tocotrienols have been shown to inhibit the growth of new blood vessels to rapidly growing tumors and inhibit growth and proliferation of cancer cells.9,15 Tocotrienols also sensitize cancer cells to the effects of standard chemotherapy, and astonishingly, appear capable of combating cancer stem cells, which are highly resistant to standard chemotherapy and contribute to cancer recurrences.9 They also blunt the impact of chemical carcinogens in animal studies.16
Tocotrienols also trigger apoptosis, which is the programmed cancer cell death that can prevent a tumor from ever getting a toe-hold in the body. Apoptosis is also vital in shrinking existing tumors, a factor that may account for the growing use of tocotrienols (alone or with conventional chemotherapy drugs) in patients with existing cancers.14,17
Tocotrienols have another rather unusual mechanism for fighting cancer. They appear to block an enzyme that cancer cells need for invasion and metastasis. This enzyme, called HMG-CoA reductase, is the same enzyme blocked by statin drugs.2 In fact, the combination of tocotrienols with the statin drug atorvastatin (Lipitor®) was recently shown to greatly increase inhibition of cancer cell growth.18
Tocotrienols For Cardiovascular Disease And Stroke
Tocotrienols offer many important complementary benefits to the tocopherol form of vitamin E, such as:
1. Improving Lipid Profiles
Tocotrienols help lower plasma cholesterol levels by blocking HMG-CoA reductase. This enzyme is a rate-limiting step in producing cholesterol, so blocking it is an effective means of lowering cholesterol levels. In fact, the common statin drugs used for lowering lipid levels also operate by inhibiting HMG-CoA reductase, although they do so by a different mechanism.4,19-21
Human research shows that tocotrienol supplementation can lower total serum lipids by up to 23%, total cholesterol by 30% , and LDL (bad) cholesterol by 42%. Not all human studies show this dramatic reduction in LDL and cholesterol.22 And animal studies demonstrate significant reductions in lipids, with the added benefit of reducing lipid oxidation; a precursor to the arterial damage that leads to stroke and heart attacks.23
Tocotrienols also can lower dangerous forms of apolipoproteins, which are lipid-carrying proteins that can increase cardiovascular risk.24 Alpha tocopherol has no effect on serum lipids.25
2. Reducing Homocysteine
Tocotrienols have also been found to reduce blood levels of homocysteine, another important contributor to cardiovascular disease.
When scientists used a tocotrienol-rich fraction in a rat study to reduce plasma homocysteine and heart oxidative stress, they discovered that it proved more powerful than folate, the standard homocysteine-reducing vitamin.2
And in rabbits, tocotrienol supplementation after a high-fat diet significantly lowered a host of markers of both inflammation and heart muscle damage.26
3. Protecting Against Ischemia
If a vessel does become blocked, tocotrienols offer potent resistance to the loss of blood flow known as ischemia, which is generally involved in the development of heart attack or stroke.26 This was powerfully demonstrated in a study of rabbits, in which supplementation not only lowered their lipids, but also protected their heart muscle from damage by ischemia induced in the laboratory. This was especially true of the alpha- and gamma-tocotrienol, which reduced the area of heart muscle damage significantly.26
4. Guarding Against Stroke-Related Brain Damage
Acute ischemic stroke (reduced blood flow to an area of the brain) remains a leading cause of death and disability worldwide.27 Oral tocotrienols have been shown to protect against and minimize stroke-related brain damage in animal models.3,6,27,28 This protection is the result of several independent mechanisms. Tocotrienols work by:
- Slowing the conversion of arachidonic acid (the most abundant brain fatty acid) into pro-inflammatory molecules, thereby reducing the inflammation that arises after an acute stroke.28,29
- Reducing the effects of specific oxidant damage-inducing molecules in brain tissue.3
- Increasing the recruitment of arterioles to rapidly restore blood flow to areas injured by stroke.4
5. Improving Metabolic Syndrome
In an exciting look ahead at what the future may hold in human studies, preclinical research has shown that tocotrienols can reverse many changes seen in metabolic syndrome, including improving lipid profiles, reducing atherosclerotic lesions, lowering blood glucose and markers of glycation, normalizing blood pressure, and inhibiting new fat deposits.30,31 At the functional level, tocotrienols improve heart muscle function, improve glucose and insulin tolerance, and reduce infiltration of inflammatory cells into heart muscle.30