Sunscreens and Cancer: Your Options

Now that summer is in full force and the sun is brutal most of the time, especially here in Houston, many of us feel we need to cover our bodies with sunscreen every day before we go out. But is that really such a good idea? And will it really prevent cancer?

I have always found it intriguing that while humans evolved under the sun – not in caves – the sun is increasingly blamed for skyrocketing skin cancer rates. If the sun was truly the culprit, and sun block a major defense, wouldn’t rates of skin cancer be dropping and not rising?

The facts, however, tell a different story. Today skin cancer is more common in the United States than all other forms of cancer combined. Its incidence is also growing faster than all other cancers, increasing by 6-7% each year.

To understand the possible role of the sun in this epidemic and how sunscreens may be playing into it, consider that life evolved under a variety of different conditions that could be
both beneficial and harmful, developing complex relationships with the environment. Nothing illustrates this point better than our relationship with air: while we die in minutes without it, oxygen is also a source of free radicals, now known to cause aging and cancer. To counter this, the body developed the ability to use certain pigments and other components of food
– today identified as antioxidants – to protect itself from the harmful effects of oxygen.

Likewise, ultraviolet rays in sunlight are known to cause aging and damage to the skin – yet they are also the primary source of vitamin D, which has been shown to have major immune-regulating effects and to prevent a range of cancers including colon cancer, breast cancer and melanoma.

The most common form of skin damage resulting from exposure to the sun is raised and sometimes scaly brownish patches of skin known as actinic keratoses. These appear in areas that have had repeated exposure to the sun and are common in people over the age of forty. While benign, they are known to be precancerous lesions that, in about 20% of cases, evolve to a form of skin cancer known as squamous cell carcinoma (SCC). SCC rarely metastasizes and is therefore not considered to be a major threat to life, but it cannot be ignored or it will eventually turn deadly.

Another form of skin cancer that is also generally thought of as resulting from sun exposure is basal cell carcinoma (BCC). Like SCC, BCC is also relatively benign in its course and the difference between the two pertains mainly to the appearance and the layer of skin in which they develop.

The type of skin cancer everyone worries about, of course, is melanoma. This one is far from harmless. It is aggressive, has a tendency to metastasize to other parts of the body, and often recurs after treatment, sometimes years later. While there is probably a relationship between melanoma and the sun, it is a more complex relationship than for other types of skin cancer because melanoma does not simply result from sun damage to the skin.

In fact, melanoma often appears in areas of skin that are rarely or never exposed to the sun. It affects office workers more than outdoors workers, and its rate has been skyrocketing especially in countries like Norway, where the sun is a rare commodity. Though not conclusive evidence of harm, rates of melanoma are highest in developed countries where sales and use of sunscreen are also the highest. The thinning of the ozone layer, which had been suspected of being a contributing factor, has been ruled out since it has been shown that, aside from the hole in the ozone in the Antarctic, the ozone layer in the atmosphere has not changed.

Among factors that have been shown to correlate with the risk of melanoma, the ability of skin to tan was found to reduce the chance that a person may develop the disease. This is
interesting because it suggests that tanning itself protects from melanoma and, if this is the case, inhibition of tanning through sunscreens could increase the risk. Of even greater interest is the finding that among people who were treated for melanoma, those who spent time in the sun had the lowest recurrence rates.

Sunscreens have been proven to be most beneficial in delaying the onset of actinic keratoses and SCC. However, when it comes to BCC the research starts to become fuzzy and does not show clear evidence of benefit from sunscreen. For melanoma, results are decidedly mixed. Most studies are neutral and show that there is no benefit – but also no detriment – to using sunscreen; yet what is remarkable is that there are more studies showing that sunscreen use increases the rate of melanoma than there are studies showing a beneficial effect.

There are two possible explanations for this: one is that sunscreens inhibit the skin’s ability to synthesize vitamin D, which has been shown to protect against melanoma; and the second is that they prevent tanning, which (as noted above) may be protective.

Another potential problem with sunscreens and cancer is that all chemical sunscreens block UVB to a far greater extent than UVA, regardless of what labels may lead you to believe.

UVA and UVB are the two major forms of ultraviolet light that come from the sun. While both can cause aging of the skin and cancer, only UVB causes tanning … hence the major focus on blocking UVB. However, UVB is also what gives us vitamin D. Therefore, it is conceivable that sunscreens leave us exposed to harmful levels of UVA while inhibiting the tanning and vitamin D that protect us.

Incidentally, the only types of sunscreen that protect equally against UVA and UVB are the traditional ones containing titanium or zinc oxide. Therefore, my recommendation is to limit time in the sun but not avoid it completely. If you are going on vacation and are planning to spend extended periods of time under the sun, then use a sunscreen with titanium or zinc.

For a comprehensive and entertaining review of the pros and cons of sunscreens for melanoma, watch this video:

An interesting study that came out last December showed that a form of vitamin B-3 called niacinamide can protect from actinic keratosis, SCC and BCC better than any existing sunscreen. This study was of particular interest to me because I have long suspected that changes in our diet, and other nutritional factors, could be causing the skin cancer epidemic to a far greater extent than the sun. You can read about the study here:

The best way to benefit from niacinamide for skin health is to apply it directly in gel form to areas of the skin that have sun damage or are exposed the most. Incidentally, topical niacinamide has long been known to help the skin and, even before its benefit for cancer was known, research had shown it to be equally effective as antibiotics in clearing acne. A topical niacinamide product providing the concentration used in studies, called Metazene, is available from my office or can be ordered online from

The medical management of BCC and SCC involves surgical removal. This works, but does not prevent recurrence, which is common, and causes scarring that can become unsightly especially after repeated procedures.

Though few people know about it, there is a natural alternative to surgery that has been proven effective, is non-invasive and does not lead to scarring. It is a cream made from an
eggplant extract called BEC-5 or Curaderm. When applied as directed, this cream causes the patch of skin containing a lesion to look progressively more like dead skin, until it finally falls off within a couple of months to reveal healthy skin – not scar tissue – underneath.

Although there is research proving the effectiveness of this product, it does not work when there is a recurrence of skin cancer under scar tissue from a previous procedure. This is because the cream penetrates readily through skin but through not scar tissue.

In the U.S. Curaderm is considered an unapproved drug and it is likely to remain this way because it cannot be patented given that it is natural, and the manufacturers will not invest the millions it takes to gain FDA approval. Nevertheless it is legal to order it from a foreign provider as long as it is for personal use. Here is one reliable source: .

When it comes to melanoma the situation is far more complex, but if you are concerned about it, and especially if you have had it and want to do everything possible to prevent a recurrence, it makes sense to screen your levels of vitamin D on a regular basis through a blood test that is available from my office. If you are not achieving optimal levels of vitamin D from the sun alone, the next best choice is to take it as a supplement.

In addition, research has shown that two very simple nutrients help prevent melanoma and even inhibit its growth when present: the mineral selenium and an extract of the vegetables of the brassica family. It may therefore be a good idea to take 200 mcg a day of selenium and to eat broccoli, cauliflower or a related vegetable on a daily basis. If you really hate these vegetables, you can now find brassica extract as a supplement though the ideal protection seems to be achieved from eating the vegetables regularly.

In summary, here is my advice for dealing with sun exposure:

1) To protect your skin and at the same time enable your body to make optimal amounts of vitamin D, enjoy regular short periods of unprotected sun exposure. For most people a few minutes are enough, and this can be monitored by testing your vitamin D levels.

2) If you are going on vacation and are planning to spend extended periods of time in the sun use a traditional sunscreen containing zinc or titanium oxide. These are the only sunscreens that block UVA and UVB equally.

3) If you are concerned about melanoma and optimal immune system health, have your vitamin D levels checked regularly. This is a simple blood test available from my office. If your levels are low or if you are not getting regular sun exposure, consider supplementation.

4) If you have sun-damaged skin, including actinic keratosis, or if you have been diagnosed with basal cell or squamous cell carcinoma and would like to avoid surgery, consider ordering Curaderm (BEC-5) from the site given above.

5) To prevent these same types of skin cancer consider applying niacinamide in a gel called Metazene to your skin. This product is available from my office and can be ordered from

6) Take a selenium supplement on a daily basis.

7) Don’t forget to eat your broccoli!

Comments are closed.