Vitamin E - like all vitamins - plays an essential role in the body. Stored in adipose tissue, it has significant antioxidant properties and is a highly-effective free radical scavenger. It protects the body’s cells from harmful oxidative stress and degeneration, thus fighting the effects of aging. It is also involved in many metabolic processes (neuromuscular, for example) as well as in regulating cell growth.
As a result of the very many studies conducted on vitamin E, we now know that it protects against cardiovascular disease by preventing the formation of blood clots and reducing levels of ‘bad’ LDL-cholesterol. It may thus lower the risk of heart attack and stroke. Other studies have demonstrated vitamin E’s benefits in preventing certain forms of cancer (such as prostate cancer in smokers), and infectious diseases (via the immune system). Last but not least, a study published in the report of the American Psychiatric Association suggests vitamin E has a mildly preventive effect in early Alzheimer’s disease.
Vitamin E is readily available from the diet – vegetable oils such as sunflower, rapeseed and olive oil are all good sources. It is also present at beneficial levels in nuts such as almonds and hazelnuts and in dark green leafy vegetables, particularly cabbage. What is important in ensuring a good intake that meets your daily requirements (12mg/day for adults) is to eat a variety of foods rich in vitamin E. By way of example, one tablespoon of sunflower oil (approx. 15ml) provides 6mg of vitamin E, and the same quantity of wheat germ oil provides 21mg.
Relatively rare in humans, vitamin E deficiency is generally only seen in people with gastrointestinal malabsorption diseases (for example, Crohn’s disease). That doesn’t mean, however, that everyone else is consuming enough vitamin E to meet their needs. A study conducted in the US and Canada, published in the Journal of the Academy of Nutrition and Dietetics, showed that the vitamin E requirements of Americans were not being totally met by their diet. Deficiencies can manifest as muscular and neurological problems.
The term ‘vitamin E’ actually covers eight different compounds: four tocopherols (alpha-, beta-, gamma- and delta-tocopherol) and four tocotrienols (alpha-, beta-, gamma-, and delta-tocotrienol). Tocotrienols are distinguished by their three double bonds. With a greater number of unsaturated bonds, they penetrate more easily to the heart of the body’s cells. These double bonds also increase the molecules’ antioxidant capacity.
Of all the forms of vitamin E, alpha-tocopherol is the most abundant in the body. However, in order to fully benefit from the vitamin, we need to ingest all its different compounds. Though tocotrienols are less well-known than tocopherols, research suggests their properties may be highly beneficial for our health. An American study from 1995 showed that tocotrienols may reduce the risk of atherosclerotic blockage in the carotid artery. According to several studies conducted in the 1990s, they may also be able to control and reduce cholesterol produced by the liver, a property not shared by tocopherols. The problem is that tocotrienols are much rarer than tocopherols and are therefore less available in supplement form.
Vitamin E is available in two forms – natural (as provided by the diet and by supplements) or synthetic (provided by supplements only). The natural form is better absorbed by the body – its bioavailability is up to twice that of its synthetic counterpart. You’d need to take 1.5-2 times more synthetic vitamin E to obtain the same effects. Note too that most of the vitamin E in capsule form – whether natural or synthetic – consists primarily of tocopherols, particularly alpha-tocopherol. It’s therefore well worth reading the labels of vitamin E supplements carefully to establish the exact composition. Ideally, they should contain all eight compounds, or at least all four tocopherols. Another point worth noting is that vitamin E acts synergistically with other antioxidants and it is therefore beneficial to combine it with vitamin C.
A senescent cell is one whose life cycle has come to a permanent end. In the normal scheme of things, such cells are eliminated from the body by the immune system. But in some cases, this fails to happen and they accumulate in tissues, with potentially serious consequences for health.