Vitamin E

Vitamin E (tocopherols)

Tocopherols occur in nature as oily liquids. Chemically speaking, tocopherols are chroman derivatives with an isoprenoid side chain (phytol) in the 2-position. Tocopherol belongs to the group of terpenoids.

Task/function

The most important naturally occurring compound with vitamin E activity is α-tocopherol. γ-tocopherol, which is mainly found in soy products, shows only low activity. One of its most important functions is that of a lipid-soluble antioxidant, which is able to protect polyunsaturated fatty acids in membrane lipids, lipoproteins and depot fat from destruction by oxidation (lipid peroxidation). Free radicals would attack the double bonds of the fatty acids in the cell and organelle membranes. Tocopherol acts as a radical scavenger by itself becoming an inert, mesomerically stabilized radical: Vitamin E has a function in the control of the gonads in some animals and is therefore also known as an antisterility vitamin. The human body can store it so that a single dose can be effective for a long time. Vitamin E is also said to protect against heart attacks, cancer and Alzheimer's, slow down the ageing process, protect red blood cells, strengthen muscles and nerves, act in the metabolism of steroid hormones, improve blood circulation and prevent vascular deposits. When preparing food, the average cooking loss is 10%. When frying fat is reheated, the remaining vitamin is destroyed.

Potential health benefits of vitamin E

As an antioxidant, vitamin E is often touted for its ability to fight oxidative stress that damages cells over years and decades. Some health practitioners believe this can prevent or delay some age-related conditions including heart disease, diabetes, Alzheimer's disease and cancer. It is also believed that these effects can delay the aging process when vitamin E is applied to the skin as a skin lotion or cream (2).

Other potential health benefits include the following:

Vitamin E may prevent pregnancy complications

Vitamin E is commonly used in the late stages of pregnancy to reduce the risk of pre-eclampsia - a devastating complication caused by a rapid rise in blood pressure. However, a study review published in 2015 found insufficient evidence to support this type of use (3).

Vitamin E could have a positive effect on the nervous system

Vitamin E supports the transmission of electrical signals between nerve cells in the brain and body. For this reason, some believe that vitamin E could help in the treatment of nervous system disorders such as Alzheimer's or epilepsy. However, the scientific data on this is mixed. Although there is some evidence that vitamin E can slow memory decline in patients with moderately severe Alzheimer's disease, there is little to no evidence that it can prevent disease progression or even lead to an improvement in the disease state (4). One area where vitamin E supplements may be helpful is in the treatment of ataxia - a congenital movement disorder associated with severe vitamin E deficiency. Vitamin E supplements are a standard treatment for this condition and have been shown to improve mobility in some cases (5). Vitamin E has also been shown to be helpful in preventing drug-induced peripheral neuropathy. There is evidence that vitamin E supplements can prevent the destruction of the insulating protective layer of nerve cells known as the myelin sheath by the long-term use of certain drugs including HIV drugs or chemotherapy drugs such as cisplatin (6). However, a 2016 meta-analysis suggested that vitamin E was not helpful in preventing peripheral neuropathy due to chemotherapy (7).

Vitamin E could be helpful for eye diseases

Vitamin E is an integral part of eye health, supporting the repair of the retina, cornea and mid-skin (the pigmented part of the eye). A 2015 review concluded that vitamin E supplements are associated with a reduced risk of age-related cataracts (8). Vitamin E supplements are also used to treat an eye condition known as retinopathy of prematurity. However, a 2003 study review concluded that giving vitamin E to newborns may help, but could also increase the risk of life-threatening conditions (9). On the other hand, excessive doses of vitamin E may increase the rate of vision loss in people with retinitis pigmentosa (10).

Vitamin E could help with liver disease

Vitamin E can neither prevent nor treat liver disease, but it can help slow its progression. According to a 2015 study, supplementation with 800 IU per day slowed the rate of fibrosis (scarring) in patients with non-alcoholic fatty liver disease and non-alcoholic steatohepatitis (11). However, vitamin E has little to no effect on alcohol-related liver disease. Vitamin E may also be helpful in the treatment of certain types of chronic hepatitis B.

Heart disease and cancer

The long-held belief that vitamin E can reduce the risk of heart disease and cancer is still not scientifically proven. A 2005 study review that analyzed over 135,000 patient shares concluded that there is no link between vitamin E supplementation and the risk of heart disease or cancer (12). High doses of vitamin E (400 IU or more) were even associated with a slightly reduced lifespan compared to a placebo. This may be related to the increased risk of hemorrhagic stroke that some researchers associate with vitamin E supplementation (12). There is also evidence that high-dose vitamin E supplements may increase the risk of prostate cancer (13).

Skin diseases

Vitamin E is aggressively marketed by cosmetic manufacturers as an anti-ageing compound, although current data has shown that claims such as these are exaggerated. It has also been suggested that vitamin E may help heal scars by hydrating the skin, inhibiting collagen production and reducing inflammation that can lead to tissue damage.

A study published in 1999 largely disproved these claims. This study concluded that vitamin E does nothing to reduce the appearance of scars. In addition, 33% of users developed an allergic skin reaction called contact dermatitis (14).

Occurrence

Tocopherol is mainly found in plant foods: Grains, nuts, seeds and vegetable oils, especially sprouted oils and good quality cold-pressed edible oils. Olive oil, milk and eggs are frequently mentioned as the main sources of vitamin E for humans, as well as many types of fruit and vegetables and green salads.

Particularly rich sources of vitamin E are

Wheat germ oil (174-176 mg/100 g)
Linseed (57 mg/100 g)
Sunflower oil (50-62 mg/100 g)
Walnut oil (39 mg/100 g)
Maize germ oil (31-34 mg/100 g)
Safflower oil (29-44 mg/100 g)
Sesame oil (28 mg/100 g)
Hazelnuts (27 mg/100 g)
Soybean oil (17-25 mg/100 g)
Peanut oil (25 mg/100 g)
Almonds (25 mg/100 g)
Palm oil (25 mg/100 g)
Sunflower oil (25 mg/100 g)
Margarine (14 mg/100 g)
Olive oil (12 mg/100 g)
Black salsify (6 mg/100 g)
Linseed oil (5.8 mg/100 g)

Due to its antioxidant effect, vitamin E is also added as an additive (E 306-309) to foods, cosmetics (sunscreens) and paints.

Deficiency symptoms (hypovitaminosis)

Deficiency symptoms in humans are not yet known, as all forms of vitamin E are apparently sufficiently present in the diet. The following are suspected

dry, wrinkled skin
concentration problems
poor performance
tiredness
irritability
Poorly healing wounds.
Promotion of arteriosclerosis

Consequences of an overdose (hypervitaminosis absorption of vitamin A and vitamin K)

Nausea, vomiting, gastrointestinal complaints
Exhaustion, muscle weakness
Deterioration of blood clotting (occasionally in very high doses)
Vaginal bleeding (vaginal bleeding)
Worsening of diabetes mellitus, high blood pressure and angina pectoris (coronary artery disease and associated sudden pain behind the breastbone)
Danger to life

Possible side effects

Vitamin E supplements rarely cause side effects if the recommended daily dose is not exceeded, but this no longer applies if the dosage exceeds 300 IU per day. A 2010 study showed that taking 300 to 800 IU of vitamin E per day can increase the risk of hemorrhagic stroke by up to 22% (15). And even at lower doses, side effects such as nausea, vomiting, stomach pain and diarrhea can occur (16). Vitamin E can slow down blood clotting and should only be supplemented by people taking blood thinners such as Coumadin (warfarin) or Plavix (clopidogrel) in consultation with their doctor (1). For the same reasons, vitamin E supplementation should be stopped two weeks before planned surgery to avoid excessive bleeding. Vitamin E supplements should be avoided by people with a history of heart attacks, strokes, bleeding disorders and cancers of the head and neck (17). In addition to blood thinners, vitamin E supplements may also interact with certain other medications including the immune function reducing drug Sandimmune (cyclosporine), certain chemotherapy drugs, statins such as atorvastatin and tamoxifen (18).1

Requirement

5-30 mg per day. Recommended daily dose for adults: 12 mg (women)/14 mg (men) per day. Pregnant women and breastfeeding mothers have an increased requirement. The German Nutrition Society recommends a daily intake of 22 International Units (IU) of vitamin E for both men and women. Among foods, vegetable oils, nuts and green salads are particularly rich in vitamin E.

Requirements in sport

Vitamin E supplements are recommended for athletes because they help to limit the muscle damage caused by training, which speeds up the regeneration process. My recommendation is to take a supplement of 200-600I.U. a day with a meal.