Can Your Diet Help Prevent Skin Cancer?

The major cause of skin cancer is ultraviolet (UV) rays from the sun or from tanning machines.

About 90 percent of non-melanoma skin cancers and 86 percent of melanomas are associated with solar UV.

UV exposure generates free radicals, unstable, nasty little oxygen molecules that produce inflammation and damage cell function and your skin’s DNA.

This DNA damage can cause changes in your genes called mutations that lead to skin cancer.

Studies have shown that substances called antioxidants, including vitamins and other nutrients, may help fight off free radicals and prevent the damage they do that can cause skin cancer.

A 2002 study in the Journal of Investigative Dermatology found that UV exposure depletes antioxidants in the body. So, it makes sense that replacing these protective substances could bolster the weakened defenses.

More dermatologists than ever now advise patients to feast on foods high in these nutrients. Many also suggest applying topical products containing them, including sunscreens.

While both foods and supplements can aid in disease prevention, most nutritionists stress foods, since the interaction between different nutrients in foods is what makes them most effective.  

Vitamin C, E and A, zinc, selenium, beta carotene (carotenoids), omega-3 fatty acids, lycopene and polyphenols are among the antioxidants many dermatologists recommend including in your diet to help prevent skin cancer. 

Beta carotene in carrots
Diets high in beta carotene-rich fruits and vegetables, such as carrots, may reduce the risk of some cancers. Beta carotene also boosts the immune system’s ability to fight disease.
This nutrient can give you certain health benefits by converting to vitamin A in the body. While supplements have not proven to help prevent skin cancer, diets high in beta carotene-rich fruits and vegetables may reduce the risk of some cancers. Beta carotene also boosts the immune system’s ability to fight disease.

Where to find it: Look for orange-colored vegetables and fruits, including carrots, squash, sweet potatoes, cantaloupe, apricots and mangoes.

Lycopene
The same red pigment in lycopene that helps protect the tomato against sun damage may also help protect your skin against sun damage. A 2010 study in the British Journal of Dermatology that tracked patients regularly eating tomato paste against a control group that didn’t found that, after 10 weeks, the lycopene eaters were 40 percent less likely to be sunburned. Several reports have linked lycopene to a lower risk of various cancers.

Where to find it: This red-pigmented antioxidant is in tomatoes, watermelon, guava, papaya, apricots, pink grapefruit, blood oranges and other foods.

Omega-3 Fatty Acids
These nutrients inhibit COX-2, a chemical that promotes skin cancer progression. They are also thought to reduce inflammation. Several cancers, including skin cancer, have been strongly linked to chronic inflammation.

Where to find it: Fatty fish such as salmon, sardines, mackerel, herring and albacore tuna are chock full of omega-3s. Walnuts and flaxseed are good vegetarian sources.

Polyphenols in Tea
Studies have shown that drinking green or black tea can help prevent skin cancer. But the evidence for green tea is stronger, with numerous studies pointing to its benefits. The polyphenols in green tea are plant chemicals with powerful antioxidant, anti-inflammatory and tumor-inhibiting properties, and have been found to repair DNA in UV-exposed skin, reducing cell damage. In the lab, green tea either consumed or applied directly to the skin has helped prevent UV-triggered skin cancer by absorbing UV damage and scavenging free radicals. A recent study concluded that tea’s polyphenols may reduce your skin cancer risk significantly if you drink four to six freshly brewed cups a day.

Where to find it: In freshly brewed green or black tea.

Selenium
A recent major review of 16 studies involving more than 144,000 people reported that those with a higher intake of selenium have a 31 percent lower risk of cancer at any site and a 40 percent lower risk of cancer deaths.

Where to find it: Just one to two Brazil nuts a day provide all the selenium you need. Meats such as chicken and grass-fed beef are also rich in this mineral.

Vitamin C
Long ago, scientists discovered that some properties of vitamin C make it toxic to cancer cells. While no one has turned up convincing evidence that it prevents skin cancer or cuts skin cancer deaths, general studies have linked higher blood levels of the vitamin with a lower overall risk of cancer deaths.

Where to find it: Get your C from oranges, lemons, limes, strawberries, raspberries and certain vegetables, including leafy greens, broccoli and bell peppers.

Vitamin D
The best-proven benefits of vitamin D are bone-building and immune-boosting, but a 2011 study from the national Women’s Health Initiative found that women with a history of nonmelanoma skin cancer who took low levels (400 international units, or IU) of vitamin D plus calcium supplements reduced their melanoma risk.

There have been similar findings with breast, colon and rectal cancer. The skin produces vitamin D in response to sun exposure. But since unprotected sun exposure causes skin damage, you should use food and supplements to get your optimal level of Vitamin D. Look for vitamin D3, the most effective form of the vitamin. Early and late sun exposure is fine but it needs to be before 10 am and after 3 pm adjusted to daylight saving times.

Where to find it: If you can stomach the taste, one tablespoonful of cod liver oil has more than twice the recommended daily allowance of vitamin D. Fatty fish such as salmon, mackerel and tuna are excellent sources as well. 

Vitamin E
In the diet, this vitamin has many abilities that could make it an effective skin cancer preventive. A proven antioxidant, it helps prevent damage from free radicals, absorbs energy from UV light, has potent anti-inflammatory effects and improves the ability of skin and veins to act as protective barriers. 

Where to find it: Rich sources of vitamin E include almonds and other nuts, sunflower and other seeds, spinach, soybeans and wheat germ.

Zinc
It helps keep the immune system functioning efficiently to fight cancer and other diseases. It also helps activate certain antioxidants in the body. A small 2017 study of men in The American Journal of Clinical Nutrition found that just a modest increase in dietary zinc helped replenish antioxidants and restore immune functions in the body. It increased the level of proteins involved in DNA repair.

Where to find it: You can find high amounts of zinc in beef and lamb, shellfish and legumes such as hummus, chickpeas, lentils and black beans.

Nicotinamide (also known as niacinamide) is vitamin B3. Several studies have revealed that nicotinamide reduces the rate of new skin precancer, basal cell carcinomas and squamous cell carcinomas by 23 percent in patients with a history of these lesions. When UV damages the skin, DNA repair enzymes in the skin launch into repairing the damage, but never fix all of it. The remaining damage can lead to skin ageing and skin cancers. However, both oral and topical nicotinamide replenish energy supplies in the skin that get depleted by these repairs. In this way, they bolster the immune system’s ability to fix the damage. Also, UV radiation itself suppresses the immune system, and nicotinamide reduces this suppression.

Where to find it: yeast, meat, fish, milk, eggs, green vegetables, beans, and cereal grains

Polypodium leucotomos: This antioxidant, which comes from a fern, is the key ingredient in several products, and perhaps the most prominent example of so-called “edible sunscreens” on the market today. Studies have shown that it helps prevent both UVA- and UVB-induced toxicity and DNA damage and reduces free radicals, those potentially cancer-causing oxygen molecules caused by UV exposure. A recent study showed that 240 mg of the supplement twice daily suppressed sunburn, and it has been found to extend the time outdoors before your skin starts to tan. It is also an anti-inflammatory and increases a molecule known to suppress tumours. In Central and South America, it is used in traditional medicine.

Last word: It’s important to remember that the main skin cancer [prevention is to keep your skin shielded from direct sunlight by seeking shade outdoors and wearing wide-brimmed hats, UV-filtering sunglasses and other sun-protective clothing along with sunscreen.