Foods such as black beans, carrots and sweet potato contain فيتامين أ, which is associated with a healthy immune system. Vitamin A can also help the heart, lungs, kidneys and other organs work properly.

Whilst vitamin A's benefits have been known for a while, prior studies on its link to سرطان الجلد have been mixed.

Research, led by Dr Eunyoung Cho, at Brown University, looked at the data of 121,700 women from 1984 to 2012, and over 50,000 men from 1986 to 2012.

The results showed people with the highest vitamin A intake were 17% less likely to get cutaneous squamous cell carcinoma (the second most common form of skin cancer) compared to those in the category with the lowest vitamin A intake.

Nearly 4,000 people developed squamous cell skin cancer during more than 25 years of follow-up.

Those with higher levels of vitamin A tended to be older. They also exercised more and were less likely to consume الكحول أو الكافيين. The women in the study with higher levels of vitamin A were more likely to use HRT after menopause.

The researchers also found that eating high levels of other plant-based pigments similar to vitamin A, such as lycopene in tomatoes and watermelon, was associated with decreased risk of skin cancer.

Cho said: "Our study provides another reason to eat lots of fruits and vegetables as part of a healthy diet. Skin cancer, including squamous cell carcinoma, is hard to prevent, but this study suggests that eating a healthy diet rich in vitamin A may be a way to reduce your risk, in addition to wearing sunscreen and reducing sun exposure."

The study, however, did not account for vitamin A supplements, as well as the fact that excess consumption can lead to nausea, liver toxicity, increased risk of osteoporosis and hip fracture.