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Hot topic - Vitamin E linked to shorter lifespan23 November 2004 - written by BUPA's Health information team Elderly people who take more than half the recommended daily dose of vitamin E may shorten their lifespan, according to new research carried out by the Johns Hopkins University in the US.1 What did the research show?The research showed that when elderly people took vitamin E at a dose of 400 international units (IU) (approximately 270mg) or more a day, they were more likely to die at an earlier age than those who didn't take vitamin E supplements.1 The research did not show whether low amounts of vitamin E supplements (200 IU per day or less [approximately 130mg]) increased a person's chances of dying.1 Why do I need vitamin E?Vitamin E is an antioxidant. Antioxidants are substances that are thought to "mop up" molecules called free radicals in the body. Free radicals are produced by the body's normal chemical reactions. Free radicals are thought to damage body cells, which may lead to the development of diseases such as cancer. So mopping up free radicals may stop the damage they cause.2 How much vitamin E do I need?You don't need vitamin E every day because it is a fat-soluble vitamin. Fat-soluble vitamins are stored in the liver for future use if your body doesn't need them immediately. The recommended amount of vitamin E is 4mg (6 IU) a day for men and 3mg (4.5 IU) a day for women. The current upper safety limit for vitamin E is 540mg (800 IU) a day, which is double the amount found to be harmful in this study.3 How can I get vitamin E from my diet?Vitamin E is mainly found in plant products, such as vegetable oils, soybeans, broccoli and leafy green vegetables. Meat, poultry and dairy foods only contain moderate amounts of vitamin E.4 What happens if I don't get enough vitamin E?If your body doesn't get the right amount of vitamin E, you may experience symptoms such as tiredness, shortness of breath, palpitations and anaemia. Babies who don't get the right amount of vitamin E may become irritable or bloated.4 Vitamin E deficiency is rare in the UK. There are only a few situations when vitamin E deficiency may occur.5 Why do some people take vitamin E supplements?Fat from your diet is needed for the absorption of vitamin E from the stomach and intestines. Some people's bodies are unable to absorb fat from their food and these people may require a vitamin E supplement. Some premature or low-weight babies are deficient in vitamin E and may benefit from a supplement.5 Do healthy adults need to take vitamin E supplements?For most healthy adults, eating a varied healthy diet provides all the vitamins you need so there is no need to take vitamin supplements. It is generally advisable to get your vitamins from your diet rather than supplements.5 What was concluded from this research?This research does not support the use of high-dose vitamin E supplements. The researchers showed that taking high-dose vitamin E supplements was associated with an increased chance of dying.1 Why do high doses of vitamin E reduce lifespan?This research does not explain why high doses of vitamin E caused people to die earlier. One explanation may be related to the fact that vitamin E is known to increase the effect of blood-thinning drugs. This could increase the risk of bleeding, which then increases the risk of a stroke.1 Another explanation may be that at high doses, rather than mopping up free radicals, vitamin E becomes a damaging free radical itself, and damages the cells that it normally protects.1 Further research is needed to confirm whether high doses of vitamin E cause people to die earlier, and to find out the effects of low doses of vitamin E supplements.1 How much vitamin E is found in a supplement?Single vitamin tablets can provide doses of 400 to 800 IU (270 to 540mg) a day. Multivitamin tablets usually contain 30 to 60 IU of vitamin E.1 Should I take a single or multivitamin supplement?Choose a multivitamin rather than a high dose of single vitamin E, unless your doctor or registered dietitian has advised you to. This is because vitamins and minerals work in harmony and an excessive amount of one vitamin can weaken the function of others.6 This study suggests that if you are taking a multivitamin supplement, you should make sure that it contains a low dose of vitamin E.1 Are high doses of vitamin E harmful to all types of people?This study showed that high doses of vitamin E were associated with a shorter lifespan in people over 60. Many of the participants already had conditions such as heart disease. It is not known whether the risk associated with high doses of vitamin E will also apply to younger, healthier adults. More research is needed.1 How can I make sure I get enough vitamins from my diet?
How was the research carried out?The research team looked at data from 19 studies that took place between 1993 and 2004. The studies involved more than 136,000 people aged over 60 and were located in North America, Europe and China. Nine of the studies looked at people taking vitamin E alone and ten of the studies looked at people taking vitamin E in combination with other vitamins. All of the studies used dummy pills as well as real vitamin tablets so that they could compare the death rates between the two groups. The time during which the doctors followed the patients to check how they were doing varied between the studies and ranged from 1.4 years to 8.2 years.1 Further informationBUPA resources:
External resources:
References
All websites accessed on 12 November 2004
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