It’s a popular misconception that eating onions can improve vision. There is no scientific evidence that applying or consuming onions has any positive impact on visual acuity. On the contrary, direct contact with onions can be dangerous for the eyes.

Why onions don’t improve vision
Onions contain compounds that, when cut, release a gas called sulfur oxide. This gas reacts with water in the eyes, forming sulfuric acid, which causes burning, irritation, and tearing. Trying to put onions in your eyes can cause:

Severe irritation: The burning and pain can be intense.
Corneal damage: The sulfuric acid and irritation can cause minor lesions on the surface of the eye. Increased risk of infections: Exposing your eyes to an irritant can make them more vulnerable to bacteria and infections.
Proven Ways to Improve Eye Health
If you want to improve your vision or maintain eye health, there are safe and effective, science-based methods:

Healthy diet: Eat foods rich in vitamins A, C, and E, as well as omega-3s and antioxidants like lutein and zeaxanthin. Carrots, spinach, cabbage, eggs, salmon, and citrus fruits are excellent choices.
Sun protection: Wear sunglasses with UV protection when outdoors to protect your eyes from harmful rays.

Rest: Follow the 20-20-20 rule when using digital devices. Every 20 minutes, look at something 20 feet (about 6 meters) away for 20 seconds to relieve eye strain.
Regular eye exams: The best way to ensure your vision is healthy is to see an eye doctor regularly. They can identify problems early and prescribe the correct treatment or lenses.
Don’t rely on unscientific home remedies, as they can be harmful. Your eye health is precious, so always rely on medical advice and proven methods.