Can vitamin supplements help maintain your vision?

Photo of a woman reading a newspaper

Dietary supplements containing , vitamin C or vitamin E can neither prevent age-related cataracts nor slow the progression of the condition.

Dietary supplements are often marketed using a lot of health-related claims. They are available over the counter in pharmacies, supermarkets, drugstores or on the internet. They come in many different forms, including tablets, capsules, powder or liquids. Dietary supplements contain nutrients that also occur naturally in our food, such as vitamins and minerals, but in a concentrated form and often at a higher dose. Some of these products are claimed to be especially good for your eyes and vision.

Cataracts develop when the lens of the eye gradually becomes cloudy. Your eyesight becomes increasingly blurry, as if you were looking at things through a veil or fog. In industrialized countries, cataracts are more common in older people.

According to one common theory, substances called free radicals develop in the cells of the eyes, where they can damage the tissue. Some vitamin supplements are believed to stop this damage, thereby supposedly preventing cataracts from developing, or slowing down vision loss.

Studies on preventing and treating cataracts with dietary supplements

Researchers from an international research group called the looked into the benefits of vitamin supplements for cataracts. They looked for special studies called randomized controlled trials that compared these products either with each other or with a fake supplement (placebo). They checked whether taking supplements could prevent cataracts or slow their progression.

The researchers analyzed nine studies involving a total of almost 120,000 people between the ages of 35 and 85. The participants used products with vitamin C, vitamin E and/or – that is, products thought to be especially good for your eyes – for up to twelve years.

Vitamin supplements have no benefit

The results of the studies clearly show that vitamin supplements are not effective against cataracts. People who had taken these products – in some cases for many years – developed cataracts just as often as people who had been taking a placebo. The supplements also didn't slow down the progression of the cataracts, and they didn't have any effect on eyesight. But some products had side effects: Depending on the study, between 7 and 16 out of 100 people who took had their skin turn yellowish-orange. This is a sign that they had taken too much .

Although vitamins are important for the body, a normal, balanced diet usually provides enough vitamins. So there's no reason to take dietary supplements to try to prevent or slow down cataracts. The Cochrane researchers considered the results to be so clear that they see no need for further research in this area.

Mathew MC, Ervin AM, Tao J et al. Antioxidant vitamin supplementation for preventing and slowing the progression of age-related cataract. Cochrane Database Syst Rev 2012; (6): CD004567.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

Comment on this page

What would you like to share with us?

We welcome any feedback and ideas - either via our form or by We will review, but not publish, your ratings and comments. Your information will of course be treated confidentially. Fields marked with an asterisk (*) are required fields.

Please note that we do not provide individual advice on matters of health. You can read about where to find help and support in Germany in our information “How can I find self-help groups and information centers?

Über diese Seite

Updated on November 22, 2022

Next planned update: 2025


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

How we keep you informed

Follow us on Twitter or subscribe to our newsletter or newsfeed. You can find all of our films online on YouTube.