What is it?
Vitamin E consists of two groups of fat-soluble compounds – the tocopherols and tocotrienols. Eight of these substances have vitamin E activity plus a ninth closely related compound (delta-tocomonoenol) which was discovered in kiwifruit skin in 2009. Alpha-tocopherol is both the most active form and the main source of vitamin E in the UK diet.
Because vitamin E activity comes from different molecules it is often expressed in International Units (IU) rather than milligrams.
- 1 IU = 0.67 mg alpha-tocopherol equivalents
- Conversely: 1mg vitamin E = 1.5 IU.
What does it do?
It is a powerful antioxidant, and its main function is to protect fats in the body from damaging chemical reactions known as oxidation. In this role it helps to protect cell membranes, nerve sheaths, artery walls and circulating fats (cholesterol, triglycerides and free fatty acids) as well as body fat stores. It has been suggested that this antioxidant action of vitamin E may prevent or delay the onset of chronic diseases associated with oxidative stress such as coronary heart disease, arthritis and cataracts.
Where can we get it?
It is mainly found in foods containing ‘good’ fats such as wheatgerm oil, avocado, unprocessed wholegrain cereals, nuts (especially almonds) and seeds (especially sunflower seeds). Small amounts are also found in green leaves, fruit such as kiwifruit, tomato and mango, and in the fatty parts of meat.
How is vitamin E depleted?
It is relatively unstable and breaks down when food is processed so that heating destroys around 30% of the vitamin E present. Freezing foods destroys up to 80% – fresh raw foods, fortified products and supplements are therefore the best sources.
The EU recommended daily amount is 12 mg (18 IU). Average intakes from food in the UK are lower than this at an average of 9.3 mg for UK males aged 20–59 years and just 7.8 mg for females of a similar age.
Lack of the vitamin has a harmful effect on the nervous system and can produce symptoms such as lack of energy, lethargy, poor concentration, irritability, muscle weakness and poor co-ordination. Rarely, a severe, long-term deficiency (usually due to malabsorption) can lead to serious effects such as blindness, dementia and abnormal heart rhythms if not recognised and treated.
How to boost your intake
Avocado is a rich source and can be added to sandwiches, smoothies and salads as well as being used to make dips like guacamole. Nuts and seeds can be used to top yoghurt and porridge in the morning and can be being eaten alone as a snack. Drizzling olive oil over vegetables and using it in dressings can also add vitamin E to you diet. Switching to unprocessed versions of carbohydrate-rich foods such as grains, pasta and bread can also help you to increase your daily intake.
It can be difficult to meet your recommended daily intake of the vitamin, especially if you are following a low-fat way of eating, so supplements can be useful such as Healthspan Vitamin E, 90 vegan capsules £11.45.
Different vitamin E molecules have different symmetry, rather like a left- and right-hand glove. Natural source vitamin E is the most active as it only contains molecules of one symmetry and is known as d-alpha tocopherol. Synthetic alpha-tocopherol is less biological activity as it contains both left- and right-hand symmetry molecules (dl-alpha tocopherol).
Therefore, look for a supplement that supplies natural source vitamin E (d-alpha tocopherol).
Because it’s fat soluble, the absorption depends on the presence of dietary fats and oils so take supplements after food.
What to avoid
Ensure you have a good intake of vitamin C as this regenerates vitamin E after it has acted as an antioxidant so it can work again.
Do not exceed manufacturer’s stated dose except under medical advice. Despite being a fat-soluble vitamin that is stored in the body, vitamin E is relatively non-toxic. High doses can cause headache, muscle weakness, double vision, tiredness and bowel looseness, however.
The tolerable upper intake level for long-term use from supplements is suggested as 300mg (450 IU) in the EU.
Vitamin E = effective anti oxidants and good fats is the latest addition to our A to Z of vitamins and minerals – a guide by Dr Sarah Brewer, who is the Medical Director at wellbeing brand Healthspan, and Rob Hobson, a Registered Nutritionist. For more in this series visit our Nutrition channel.Tags: Rob Hobson, Sarah Brewer, Vitamin E Last modified: June 12, 2023