Vitamin D is known as “the sunshine vitamin” because sunlight spurs its creation in the body. A new study suggests that one of its counterparts, vitamin A, might be the anti-sunshine vitamin — in the sense that it seems to lower the risk of one of sunlight’s potential ill effects.
Cutaneous squamous cell carcinoma is the second-most-common kind of skin cancer for those with fair skin. Though rarely fatal, it can destroy healthy tissue and affect the lymph nodes and other organs. According to a report released on Wednesday, researchers at Brown University have found that consuming high levels of vitamin A can result in a 17% reduction in risk for acquiring the affliction.
Published in the American Medical Association’s JAMA Dermatology journal, the study analyzed the results of two previous studies that between them followed some 173,229 subjects — the majority of them white, and thus at higher risk of developing skin cancer than those with darker skin — for 24 to 26 years.
Study participants, all of whom reported details of their diets on multiple occasions, were grouped into five categories according to their consumption of foods high in vitamin A. Those with the highest level of intake (consuming the equivalent of one medium baked sweet potato or two large carrots every day) were 17% less likely to get skin cancer than those with the lowest level (whose diet included the daily equivalent of a third of a cup of sweet potato fries or one small carrot).
The study found that eating foods with high levels of certain compounds other than vitamin A — like lycopene, found in watermelon and tomatoes — was also associated with lower skin cancer risk.
These findings should be of particular interest to those living in areas with above average rates of skin cancer. It’s the most common cancer in the United States, with more than 90,000 new cases of melanoma, the deadliest form of skin cancer, every year. These are the states with the most skin cancer.
In addition to its apparent preventative effect on skin cancer, vitamin A is important for good eyesight, bone and tooth health, and formation and maintenance of skin and mucus membranes.
The authors of the Brown University study warned that they had not proven a cause-and-effect relationship between vitamin A and decreased skin cancer risk, but that if it proves impractical to conduct more conclusive clinical trials, “a large-scale prospective study like this is the best alternative…”
Besides sweet potatoes and carrots and most other orange or yellow fruits and vegetables, foods high in vitamin A — or in substances that can be converted to it — include eggs, broccoli, spinach, most dark green leafy vegetables (like kale, among others), fortified breakfast cereal and skim milk, and cod liver oil. Many of these are considered superfoods — and these are the best superfoods to live a healthy lifestyle.