Red onions are a nutritious vegetable containing vitamin C, antioxidants, and sulfur-containing plant compounds. Adding them to your diet can contribute to an overall healthy eating pattern, but the claim that eating raw red onion can restore vision, remove cataracts, or eliminate the need for glasses is not supported by reliable medical evidence.
Vision problems have many different causes. Nearsightedness, farsightedness, astigmatism, cataracts, glaucoma, retinal conditions, and other eye diseases require different forms of evaluation and treatment. Eating onions cannot reverse these conditions.
That said, onions can still have a place in an eye-friendly diet. Their antioxidants contribute to overall nutrition, while a diet containing a variety of vegetables and fruits provides nutrients important for maintaining normal eye function.
A simple way to enjoy raw red onion is to add a small amount to salads, sandwiches, beans, tomatoes, or homemade salsa. If the flavor is too strong, soaking sliced onion briefly in cold water can make it milder.
