Road Test: Vitamin E Supplements
Vitamin E has had a slippery ride since its discovery in 1922, when it was hailed as a virtual cure-all. Our bodies can’t make vitamin E; we have to obtain it from either food or supplements. Soya and wheatgerm oils are concentrated natural sources, and it’s also plentiful in nuts and grains, so deficiency is rare. Nevertheless, those on low-fat diets or who have trouble absorbing fats may not be getting enough.
Four tocopherols and four tocotrienols make up the vitamin E family. Foods contain all eight, whereas most vitamin E supplements contain only alpha-tocopherol, which nutritionists believe the body absorbs most (Curr Med Chem, 2004; 11: 1113- 33). The full impact of supplementing with only one member of the E family over the others is not fully known. But we may be missing out on important benefits.
For example, tocotrienols, widely available in whole grains, may have a role in preventing cancer and reducing the risk of heart disease (Biochim Biophys Acta, 1993; 1166: 163-70; Lipids 1995; 30: 1179-83). In particular, gamma-tocotrienol appears to lower blood cholesterol. Among the tocopherols, gamma-tocopherol may help prevent cancer, especially of the prostate (J Natl Cancer Inst, 2000; 92: 2018-23).
But taking alpha-tocopherol can significantly reduce levels of gamma- and delta-tocopherol, according to recent evidence (J Nutr, 2003; 133: 3137-40).
Mixed messages
Research into the benefits of vitamin E supplements is, at best, mixed (see lower box, page 2). Vitamin E, as an antioxidant and anticoagulant, should help to prevent heart disease. It can reduce LDL, the ‘bad’ cholesterol, and prevent blood from clotting (Curr Atheroscler Rep, 2002; 4: 373-80), which is why it’s not recommended for patients taking blood-thinning drugs such as warfarin or aspirin.
In the 1980s, two major studies of more than 120,000 men and women showed that high daily intakes of vitamin E resulted in 40-per-cent less heart disease than low intakes (N Engl J Med, 1993; 328: 1450-6; N Engl J Med, 1993; 328: 1444-9).
Yet, seven trials of more than 80,000 people, using dosages up to 800 IU/day, concluded that vitamin E offered no protection against either cardiovascular disease or stroke (Lancet, 2003; 361: 2017-23).
But some studies have found considerable benefit for heart-related problems. In patients with established cardiovascular disease, high-dose supplements (400-800 IU) lowered heart-attack risk and prolong-ed life by 77 per cent (Lancet, 1996; 347: 781- 6); 300 IU/day improved blood circulation in the legs (intermittent claudication) presumably by thinning the blood (Int J Vitam Nutr Res Suppl, 1989; 30: 56-68). In addition, angina, the pain due to narrowed blood vessels, was also eased by vitamin E supplementation (JAMA, 1996; 275: 693-8).
As for cancer, in general, the positive results found in the lab and in animals have not been seen in human trials. However, vitamin E can lower the risk of bladder cancer (Am J Epidemiol, 2000; 152: 1145-53).
Anti-ageing effects
Vitamin E can reduce pain in rheumatoid arthritis (Z Rheumatol, 1998; 57: 207-14) and, in one large US study of nearly 30,000 women, supplemental vitamin E was found significantly to reduce the incidence of RA (Am J Epidemiol, 2003; 157: 345-54).
In a study lasting 19 years, a daily cocktail of vitamins E (3200 IU) plus C (3 g) was able to halt the progression of Parkinson’s by about two and a half years (Arch Neurol, 1992; 32: S128-32). Here, vitamin C may be important as most later studies have failed to confirm the benefits of E alone in Par-kinson’s. Vitamins C and E can also prevent dementia (Arch Neurol, 2004; 61: 82-8). In a controlled trial of patients with moderate Alzheimer’s, 2000 IU/day of vitamin E extended life by nearly eight months (N Engl J Med, 1997; 336: 1216-22).
As the heart-disease evidence suggests, vitamin E improves blood flow, partly by thinning the blood and partly by keeping blood vessels open. This is thought to also apply to the brain, thereby helping to prevent dementia and Alzheimer’s (Nutr Rev, 2000; 58: 109-11).
The products
Our vitamin E supplements came from catalogues, the Internet, healthfood shops and supermarkets, and we were struck by how expensive they could be.
In addition to cost, we gave points for coming from a natural source, containing more than just alpha-tocopherol, infor-mative labels, and being GM-free and/or vegetarian/allergy/gluten-friendly.
Most of the products provided the minimum daily amount to derive benefit (400 IU), which is completely safe. In fact, four times that is still considered safe (Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids, Washington, D.C.: National Academy Press, 2000: 249-59).
Natural E derived from soybeans keeps the price down, but has disadvantages. The plants may be genetically modified, and soya doesn’t have the rest of the vitamin E family. Adding the other seven types may increase the health benefits.
An ideal source of full-spectrum vitamin E is palm oil, which is also GM-free. But few products on the market (and none in our survey) are made from palm oil, no doubt to keep in line with upcoming EU regulations requiring vitamin E products to contain nothing but alpha-tocopherol.
Overall, we felt that many of the available products lack credibility, and most of the labels left something to be desired.
Vitamin E 600 IU (liquid) aaaaa
Distributor: BioCare
Price: lb22.60 for 120 gel caps
BioCare was one of the first to source GM-free plant materials for its E products. This product contains 400 IU of d-alpha-tocopherol and 150 mg of gamma-tocopherol, thought to aid uptake. The vitamin E here is emulsified to allow immediate dispersal in the gut, making this especially good for those with malabsorption problems. This is a well-thought-out product at a moderate 19 p/capsule.
Natural Vitamin E-400 iu
with tocotrienols aaaa
Distributor: Holland & Barrett
Price: lb5.99 for 30 capsules
H&B has added 35 mg of tocotrienols to its 400 IU of d-alpha, and only loses a point for not stating the source of the vitamin E on the label. Costing a moderate 20 p/capsule, it’s a stand-out among the high-street brands.
E-Team aaaa
Distributor: Vitamin Research Products
Price: lb22.95 for 60 capsules
Although a relatively low dose of 240 IU of natural vitamin E (65 per cent esterified d-alpha-tocopheryl succinate and 35 per cent mixed tocopherols), each capsule also contains 13 mg of tocotrienols. It is claim-ed that these “may” make it “40 times more potent than an equivalent amount of standard vitamin E”. The most ‘complete’ of our samples, it loses a point because of the price-a whopping 38 p/capsule.
Vitamin E 400 iu mixed softgels aaaa
Distributor: Solgar
Price: lb16.25 for 100 capsules
Solgar’s offering contains d-alpha-tocopherol from soybeans. At 16 p/capsule, it is sugar-/salt-/starch-free and suitable for vegetarians, and includes 17 mg of mixed tocopherols, making it more effective than others with about the same pricetag.
Vitamin E 400 iu natural dry source aaa
Distributor: Vega
Price: lb6.49 for 30 capsules
GM-free and vegetarian, the label says d-alpha-tocopherol but, in fact, it’s a mixture of natural esterified tocopheryl acetate and succinate. Esterified vitamin E has a slightly lower activity in the body than d-alpha-tocopherol (see upper box, page 2); most of us probably don’t need it, but it is helpful for those who have a problem dig-esting fats. At 22 p/capsule, it doesn’t compare well with BioCare’s product, which is also easily digested and includes gamma-tocopherol.
Vitamin E 400 iu natural source aaa
Distributor: Healthspan
Price: lb14.95 for 240 capsules
Mail-order brings the price down. The label doesn’t declare the source of the natural d-alpha, but it’s liable to be soya. It is vegetarian and gelatine-free, but there’s no declaration about being GM or not.
Vitamin E 400 iu aaa
Distributor: ZipVit
Price: lb9.95 for 200 capsules
This no-frills mail-order product is the cheapest in our sample, and uses natural d-alpha-tocopherol, which the labelling implies is from soya. It doesn’t claim to be GM-free, but it will satisfy those consumers who require supplements free of gluten, lactose, wheat and yeast, as well as being suitable for vegetarians.
High Strength Natural Vitamin E 400 iu aaa
Distributor: Vertese
Price: lb5.19 for 30 capsules
This rings all the right bells for consumers who want GM-free, gluten-free, yeast-free and vegetarian. There’s just a tiny doubt as to its contents. Although the word ‘natural’ is on the label, it doesn’t state that it contains d-alpha-tocopherol. At 17 p/capsule, we should know more.
Natural Source Vitamin E 800 iu aa
Distributor: Boots Company PLC
Price: lb11.50 for 30 capsules
Unusually high dose for a mass-market manufacturer, this would appeal to the elderly who are looking for something to help maintain healthy brain function. Although you get double the usual dose for the price, considering these contain no other tocopherols or tocotrienols, the pricetag doesn’t seem justified.
Vitamin E 400 iu aa
Distributor: Seven Seas
Price: lb5.99 for 60 capsules
The only synthetic vitamin E product in our selection, it’s an esterified compound, but it’s vegetarian and has a low pricetag.
Some manufacturers believe that synthetic vitamin E may be useful for those who are sensitive to supplements derived from soya or wheat, or who have trouble digesting fats. If this is the case, however, BioCare’s product or a dry form such as Vega’s supplement may be better choices as they are more biologically active.
Making sense of the evidence
Even a cursory examination of the evidence shows that science has not made up its mind about vitamin E. Quite why the clinical data are so contradictory isn’t clear. One reason may be that vitamin E takes a good 20 months of supplementation to become established in body tissues (Neurology, 1998; 50: 1900-2). Some experts think five years of supplements is the minimum necessary for benefits to show up (Lancet, 1995; 346: 36-8). A second reason may be just a question of dose-the higher doses seem to have the most effect. Or it may be that some studies have used synthetic vitamin E rather than the more potent natural version.
The human factor is also important. Individual absorption of vitamin E varies from 21 to 86 per cent.
Doctors’ usual response to conflicting ‘mixed’ clinical evidence is to turn their backs on it, particularly in the case of natural medicine. Interestingly, however, a recent survey of US cardiologists found that over 50 per cent of them regularly take vitamin E supplements themselves (Free Radic Biol Med, 2000; 28: 141-64).
What type of vitamin E?
Natural vitamin E, d-alpha-tocopherol, comes from vegetable oil. Synthetic vitamin E, d,l-alpha-tocopherol, is made from petrochemicals. Both come as acetate and acid-succinate, often used in powders and tablets. As an ester, tocopherol is called ‘tocopheryl’. Tocopherol may be marginally better absorbed, while tocopheryls have a slightly better shelf life and are generally water-dispersable, so do not require a fatty meal to aid its absorption.
Each type is absorbed differently and has different activity in the body. Because of the different absorption rates, labels usually use IUs (international units) and mg (milligrams). The IU equivalent indicates how active it is in the body. As the World Health Organization chose the synthetic d,l-alpha-tocopheryl acetate as the standard for vitamin E potency, 1 mg of this form of vitamin E can be considered to have 1 IU’s worth of activity in the body.
Natural forms of vitamin E are more active, so it pays to read labels before buying. Although these figures are widely accepted, they are based on animal-feed studies from the 1940s and are only approximates. Also, they do not take into account new delivery systems such as micelles, which can make the product more bioavailable, and are not necessarily applicable to vitamin E products derived from palm oil. Finally, some scientists now believe that natural vitamin E may be twice as bioavailable as synthetic vitamin E, not 1.36-1.49 times as is generally accepted (Am J Clin Nutr, 1994; 60: 397-402).
Vitamin E compound (1 mg) IU equivalent
D-alpha-tocopherol 1.49
D-alpha-tocopheryl acetate 1.36
D-alpha-tocopheryl acid succinate 1.21
D,L-alpha-tocopherol 1.10
D,L-alpha-tocopheryl acetate 1.00
D,L-alpha-tocopheryl acid succinate 0.90
- This article first appeared in the August 2004 edition of Proof!.
