Tocotrienols and red palm oil have more beneficial effects than expected

Background

Tocotrienols are the unsaturated versions of vitamin E. 


Ray Peat is not very fond of them as he wrote:

"The unsaturated tocotrienols have hardly been tested for the spectrum of true vitamin E activity, and animal studies have suggested that it may be toxic, since it caused liver enlargement." - Ray Peat

I experimented with red palm oil and found it beneficial for my skin health. As red palm oil is very rich in tocotrienols, I really wondered whether this vitamin E form is that bad. 

 

(Picture Source: www.tocotrienol.org)

 

While it is true that publications on tocotrienols only form around 1% of all publications on vitamin E, I couldn't find evidence that they cause liver damage.

Studies documenting a liver protective effect of tocotrienols

• Tocotrienols ameliorate Alcohol-Induced Hepatoxicity in Rats
• Palm tocotrienol-rich fractions are hepatoprotective in rats
• Tocotrienols reduce liver cancer incidence in rats
• Tocotrienols are more effective than alpha-tocopherol in protecting the liver from lipid and protein peroxidation in rats
• Tocotrienols protected mice livers from the damaging effects of a high-carb high-fat diet.
• Oral Tocotrienols Are Transported to Human Tissues and Delay the Progression of the Model for End-Stage Liver Disease Score in human patients

Other benefits of tocotrienols

• Tocotrienols lead to a (non-significant) increase in breast cancer survival in a randomized controlled trial in humans
• Tocotrienols protected mice from UV damage more strongly than alpha-tocopherol
• Tocotrienols protected mice from gamma irradiation

Red palm oil vs. other oils

• In hamsters, red palm oil lead to significantly less aortic cholesterol deposition and lower plasma lipid hydroperoxide values than coconut oil
• In rats, palm oil caused significantly lower serum lipid peroxides than butterfat. 
• In nonhuman primates, palm olein oil caused significantly less artherosclerosis than sunflower oil or lard
• In mice, palm oil ingestion during a high-fat diet caused significantly lower endotoxinemia than sunflower oil, rapeseed oil, and (non-significantly) milk fat

Unrefined vs. refined palm oil

• In rabbits, red palm oil caused significantly less artherosclerosis than refined palm oil
• In rats, fresh palm oil lead to significantly less atherosclerotic plaques than palm oil that was reheated several times

Conclusions

The European food safety authority concluded that tocotrienols are safe. In rats no adverse effects of tocotrienols were found for doses up to 120mg tocotrienol extract/kg bw/day (which would equal 8400mg/day in a 70kg person).
In regard to humans another review concluded: "Studies in humans at levels of 50–400 mg/day (equivalent to up to 6.7 mg/kg for a 60 kg human) for periods of 2 weeks to 18 months (56 days for the 400 mg/day study) have not been reported to cause adverse effects, other than occasional transient effects. Taken together, and given the pharmacokinetics of tocotrienols including their short half-life, consumption of 3–5 mg/kg/day, and possibly higher, would not be expected to cause adverse effects." One tablespoon (10g) of red palm oil only contains 5-7mg of tocotrienols, that is much less than any of the limits above.

In summary, I question RP's claim on the toxicity of tocotrienols. Given the repeated failures of alpha-tocopherol supplements in reducing heart disease or cancer in large trials (even the natural forms), more emphasis should be put on researching the less known vitamin E forms such as gamma-tocopherols or tocotrienols.