Osavi Primrose Oil with Vitamin A & E

Evening primrose oil (GLA)· evidence: Insufficient

Evening primrose oil is pressed from the seeds of the evening primrose plant. It contains gamma-linolenic acid (GLA), an omega-6 fat, usually around 8 to 10% of the oil.

It has been studied for skin conditions, breast pain and hormonal symptoms. Good-quality reviews have generally found it no better than a placebo, and the NHS no longer prescribes it. Studies have looked at it for many other uses, but the evidence is weak or inconsistent.

There are no authorised health claims for evening primrose oil or GLA. Most people get plenty of omega-6 fats from food already.

Typical dose: Products usually give 500 to 3,000 mg of oil a day, supplying roughly 40 to 300 mg of GLA.

Safety: Usually well tolerated; can cause mild stomach upset and headache. Speak to your GP or pharmacist if you take anticoagulants or antiplatelet medicines, have epilepsy or take medicines for it or phenothiazines, are having surgery, or are pregnant.

Research we looked at:
Bamford JTM, Ray S, Musekiwa A, et al. Oral evening primrose oil and borage oil for eczema. Cochrane Database Syst Rev 2013;(4):CD004416.
National Center for Complementary and Integrative Health. Evening primrose oil. nccih.nih.gov/health/evening-primrose-oil

Vitamin A· evidence: Limited

Vitamin A (as retinol or retinyl esters, or as beta-carotene that the body converts) is needed for vision, skin and the immune system. Adults need 600 to 700 µg a day in the UK, and most people get enough from dairy, eggs, oily fish, liver and orange and green vegetables. Deficiency is rare in the UK.

There is little reason for well-fed adults to take extra vitamin A, and preformed vitamin A (retinol) builds up in the body. The NHS advises that people who eat liver weekly should not take supplements containing vitamin A, and that pregnant women should avoid them.

Beta-carotene from food is safe, but high-dose beta-carotene supplements increased lung cancer risk in smokers in large trials.

Typical dose: Adults need 600 µg (women) to 700 µg (men) a day from all sources (NRV on labels: 800 µg).

Safety: Avoid vitamin A (retinol) supplements in pregnancy or if trying to conceive; too much can harm an unborn baby. The NHS advises not having more than 1.5 mg (1,500 µg) a day from food and supplements combined, as long-term excess may weaken bones in later life. Smokers and former smokers should not take high-dose beta-carotene supplements.

Research we looked at:
NHS. Vitamin A. nhs.uk/conditions/vitamins-and-minerals/vitamin-a
EFSA NDA Panel. Scientific opinion on dietary reference values for vitamin A. EFSA Journal 2015;13(3):4028.
Omenn GS, Goodman GE, Thornquist MD, et al. Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease. N Engl J Med 1996;334(18):1150-1155.

Vitamin E· evidence: Limited

Vitamin E is a group of fat-soluble compounds (tocopherols and tocotrienols); alpha-tocopherol is the form the body keeps and the one labels count. It is found in plant oils, nuts and seeds, and the NHS says you should be able to get all you need from your diet. Deficiency is very rare and usually linked to conditions that stop fat being absorbed.

Large, long trials of high-dose vitamin E have not shown benefits for heart disease, cancer or general health in well-nourished people. Some found possible harm: the SELECT trial found more prostate cancer in men taking 400 IU a day, and a meta-analysis linked very high doses to slightly higher overall mortality.

Natural vitamin E (d-alpha-tocopherol) is more potent per IU-labelled milligram than synthetic (dl-alpha). Mixed tocopherols and tocotrienols are marketed as closer to food, but there is little good human evidence that they make a difference.

Typical dose: UK guidance: about 4 mg a day for men and 3 mg for women (NRV on labels: 12 mg). Supplements often give 100 to 400 IU (roughly 67 to 268 mg natural vitamin E).

Safety: The FSA advises that 540 mg (800 IU) a day or less from supplements is unlikely to cause harm; EFSA's upper level for adults is 300 mg a day. High doses can increase bleeding risk, so speak to your GP if you take warfarin, other anticoagulants or antiplatelet drugs, or before surgery. Long-term high-dose use is not advised for smokers or men concerned about prostate health.

Research we looked at:
NHS. Vitamin E. nhs.uk/conditions/vitamins-and-minerals/vitamin-e
EFSA NDA Panel. Scientific opinion on dietary reference values for vitamin E as alpha-tocopherol. EFSA Journal 2015;13(7):4149.
Klein EA, Thompson IM, Tangen CM, et al. Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA 2011;306(14):1549-1556.
Miller ER, Pastor-Barriuso R, Dalal D, et al. Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Ann Intern Med 2005;142(1):37-46.

Cost per daily dose lets you compare packs of different sizes fairly.Worked out from our current prices.