Category Archives: Cancer


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Sunscreens Prevent Cancers — And Wrinkles

I’m usually quite proud of my Irish ancestry, but one unfortunate vestige of that heritage is pasty white skin that sunburns quite easily. When my mother was pregnant with me and my twin brother, the doctors discovered a large melanoma on her leg which required immediate surgery. Fortunately everyone turned out just fine, but my family history and skin color certainly put me at higher risk of developing melanoma and other skin cancers. In fact, studies have shown that getting painful blistering sunburns during childhood is a major risk factor for melanomas, squamous cell carcinomas and basal cell carcinomas later in life. This is why it’s up to parents to protect their children from the sun’s harmful effects.

Sunscreen UVA UVB broad spectrumWhat are the essentials for sun protection? For infants under 6 months of age, the American Academy of Pediatrics doesn’t recommend any direct sun exposure, as their skin is especially pale and vulnerable. For most children and adults, a combination of sunscreens, proper clothes, and avoidance of peak times from 10am-4 PM (or following your local UV Index) are the major ways to avoid damage.

How effective are clothes? These should be a first line of defence for all ages, but a plain white t-shirt only has a Sunburn Protection Factor of 7, so you could still burn quite easily through this. Most other clothes, if thicker and darker, would offer a more protective SPF 15 or higher. But I still know all too painfully well that even a dark t-shirt won’t be enough if I’m out all day swimming and playing outside.

This is when sunscreens come in handy. A good sunscreen has been shown to decrease risk for skin cancers, most impressively with squamous cell carcinomas. One Australian study showed a 40% decrease in these cancers when using a broad spectrum SPF-16 sunscreen. The evidence for protection against the much deadlier melanomas actually isn’t so strong, with the best study published in 2010 in the Journal of Clinical Oncology. This randomized controlled trial followed 1,600 persons over 10 years in Australia, a region with the world’s highest rates of skin cancers. Those who routinely used sunscreen had a 73% reduction in invasive melanoma, although the accompanying editorial questions its statistical significance. Still, I agree with their conclusion that, “the question of its efficacy with respect to melanoma prevention should no longer deter scientists or clinicians from recommending sunscreen use…In addition to sunscreen use, excess exposure to ultraviolet rays should be avoided, clothing should be used to shield skin from the sun, and sun-safe environments should be used for outdoor recreation. In addition, sunscreen use should be paired with regular self-examination of the skin.”

Sunscreen also helps prevent wrinkles and aging of the skin, as was just proven for the first time. This study followed 903 Australians for almost five years, and those who used daily broad spectrum SPF-15 had no detectable increase in skin aging.

But what exactly defines a good sunscreen? Right now your local market probably has an entire wall selling dozens of brands in bright plastic, offering a range of SPF and customized for babies, women’s faces, men… on and on, a confusing mess for us consumers. We can cut through a bit of this with the basics:

Buy a broad-spectrum: just because it says SPF-50 or even 70 doesn’t mean it’s wonderful, as the SPF rating system only measures sunburns from UV-B sunlight and not UV-A sunlight. UV-A rays don’t cause your classic lobster-red burn but it is much more sinister, penetrating deeper into your skin layers and causing more subtle and permanent precancerous DNA damage. This is why it’s crucial to buy sunscreen that follows the US FDA’s new rules and literally says “broad spectrum” on the label. This means it contains ingredients covering both UV-A and UV-B

Get SPF 30, and don’t waste your money with SPF-50 and higher: SPF-15 is a good start since it blocks 93% of UVB, but I agree with the American Academy of Dermatology to use SPF-30 as a standard. SPF-50 and above may seem impressive but clinically offer miniscule extra protection over SPF-30. SPF-30 already blocks 97% of UVB and SPF-50 only one percent more, at 98%. In fact, it’s so misleading for consumers that the EU has banned any labels over SPF-50, and the US FDA is also finalizing this long overdue limitation.

Use more than you think is enough: Research has shown a large percentage of us don’t use enough each time we apply it, and thus aren’t getting the proper protection. A typical adult should be using 1 ounce (30 ml) each time for head to toe protection.

Don’t stay out longer: Many doctors are concerned that people, especially children, stay out in the sun longer after applying sunscreen and actually increase their risks for melanomas, forgetting to reapply as directed or not using enough in the first place.

Use it all year: this may surprise many, but the AAD also recommends this. Ultraviolet rays are much weaker during other times of year but can still add up to skin damage. You should at least consider always using a daily facial moisturizer which also has at least SPF-15 and apply on your face, ears and neck. I’ve used daily facial aftershave with SPF-20 since my college days, in winter or in summer.

Sunscreens also have many approved chemicals to choose from, which further confuses your consumer choices. Some groups, especially the Environmental Working Group, claim that two common ingredients in sunscreens, oxybenzone and retinyl palmitate (from vitamin A) are harmful to health and thus should not be included in sunscreens. For example, on their web page describing oxybenzone’s dangers, they state toxic issues with “hormone disruption; reproductive effects and altered organ weights in chronic feeding studies; high rates of photo-allergy; limited evidence of altered birth weights and increased odds of endometriosis in women.” However, not one governmental FDA bans these substances, and no major medical organization agrees with their warnings. The majority of research the EWG cites are done on animals or in test tubes and not on humans, and no major research with humans has shown serious dangers. Both of these chemicals have been, and continue to be, approved as safe by the US, the EU and Canada even after more than 20 years of usage. The American Academy of Pediatrics’ position statement on sunscreens has no specific warning against these or any other FDA approved chemicals for sunscreens. The American College of Dermatology published an updated statement last summer restating their support of these two ingredients.

Fortunately, even if you still remain concerned about these ingredients, there are hundreds of sunscreens available which don’t have either of these and can offer excellent broad spectrum coverage for both you and your children. Oxybenzone isn’t even as effective as other chemicals such as avobenzone, so you could search for that instead. And you don’t need retinyl palmitate because it doesn’t even block sunlight and is only added to allegedly help with photo-aging. The American Academy of Pediatrics specifically recommends products with with zinc oxide or titanium dioxide, as they are physical barriers and don’t get absorbed. If you want more consumer guidance, you can read the independent test results from Consumer Reports or also the sunscreen ingredients guide from Consumer Search, which also reviews natural sunscreens.

Getting Some Sun — Without The Cancer

Did you know that as much as 80 percent of your lifetime exposure to sunlight happens before the age of 18? This early sun exposure slowly causes DNA damage and puts us at risk for skin cancer later on. One of the biggest risk factors for developing melanomas is the frequency of sunburns as a child. In other words, your lifetime risk factors for skin cancer can be largely predicted even before you leave high school!

The obvious solution is to use protective sunscreen or clothes at all ages – but especially in childhood. Most parents are great at protecting babies and toddlers from the sun, but only 25 percent of teens use sunscreen. Appeal to your teen’s vanity by telling them that daily sunscreen use prevents wrinkles; if greasiness is the main “ick” factor, I recommend the Neutrogena line of sunscreens (including the men’s aftershave). They absorb into the skin with a dry, light feeling. Parents should also lead by example by putting on sunscreen every day during the summer months; don’t forget the oft-neglected ears and toes. After all, it only takes 20 minutes to get sunburned in midday.

Parents and teachers can find kid-friendly educational material at SunWise (, a website created by the US Environmental Protection Agency. Studies from countries with thinner ozone layers, such as Canada and Australia, showed that regular use of SPF 30 sunscreen over several years lowered children’s risk of forming moles – an early stage in the development of melanomas. Another study showed a 50 percent drop in melanoma rates among adults who regularly used sunscreen.

However, don’t go overboard with SPF ratings. Supermarkets are now filled with expensive sunscreens outdoing each other: SPF 70, 90, even 100! Is higher better? “Definitely not,” say most doctors, including dermatologists. Any SPF over 50 is overkill and a waste of money; at SPF 30, you’re already eliminating the majority of ultraviolet rays. Last year, the US Food and Drug Administration (FDA) decided to ban any sunscreen labels over SPF 50, forcing manufacturers to simply print “SPF 50+.”

That being said, a bit of sunlight is essential to good health. People who constantly use sunscreen may actually have low levels of vitamin D, which can cause a whole other set of health issues. I generally recommend vitamin D as a supplement for both kids and adults.


(This article was originally printed in Beijing Kids magazine, where I am a contributing editor. You can click here to read the rest of my BeijingKids “The Doc Is In” columns.)

Men, Don’t Forget Sunscreen!

Sunscreen SPF protection skin cancerWe’ve already reached the summer solstice, and the sun is now the strongest it will be all year. So now’s a good time to remind everyone to use sunscreen anytime you go outside for more than 30 minutes. Even if you’re almost fully clothed, you still need to protect your face, ears and tops of your feet. Why? Because these are common “hot spots” for developing skin cancers later in life, including the deadly melanomas. I address my comments mostly to men, as I’ve noticed that men use sunscreens a lot less than women, especially as women are much more proactive in preventing wrinkles and much of their facial moisturizers already contain some SPF protection.

You could definitely argue that men have been ignored by skincare companies and thus we are thus relatively ignorant consumers. There’s some truth to that, but not anymore. Now, the men’s skincare industry has exploded in popularity, so now I am happy to report that there are a lot of men-specific skin products for men at all large markets and pharmacies, including Watsons and all the hypermarkets.

Which takes me to my main point:  everyone should be using sunscreen protection on their face every day, every season, every year. Even in the wintertime, the sun’s exposure on your ears, face and neck can lead to skin cancers, and the rates of these cancers are climbing all over the world. So here’s the perfect solution for men: most of you already shave every day, so why not use an aftershave that includes sunscreen? And then use a bit more of that onto your ears and neck? Bingo — you’re done. Every morning with your usual shave, now you’re greatly protected from the sun and also cutting down on developing wrinkles (an added bonus).

This idea sounds so obvious that you’d think the market would be flooded with such products, yes? Actually, there remain shockingly few aftershaves with SFP protection. The selection in local Chinese markets is still sparse, but my long-term American favorite is now available in China: Neutrogena’s Triple Protect aftershave, with SPF 20. SPF20 is a decent strength, not as good as SPF30 but better than the bare minimum SPF15. This brand is much pricier here than in the US (around 110 RMB, cheaper online) but I still think it’s worth it. I’ve noticed only a couple other local men’s face products with SPF protection, but hopefully the men’s health market will continue to expand.

For more information on sun protection as well as commentary on the raging debate in America about the FDA’s new rules, you can read my article last year, Is Your Sunscreen SPF 50+? Don’t Waste Your Money

PSA Test For Men Now Officially “Not Recommended”

Prostate cancer anatomyIt’s been a tough couple weeks for medical tradition. First we had all women being warned their calcium supplements may do more harm than good; now the medical community is in a tizzy over the new recommendations against using the PSA as a screening test for prostate cancer in men. Almost all older men are accustomed to getting this routine blood test, which they believed had been a good screening test for prostate cancer. The big problem with this cancer screening test, as I mentioned before, is that it is far from ideal. It misses a lot of true cancers; it over-diagnoses many benign conditions; many follow-up procedures leave the men impotent or with urinary problems; and there’s no proof that it improves survival.

This test has been on the ropes for a while but got a body blow last week when the US Preventive Services Task Force came out with their new recommendation — downgrading their 2008 recommendation from a Grade C to a D. This was a big deal: no longer is it the equivocal C level, it’s now the strongly worded “do not use PSA-based screening for prostate cancer“.

PSA testing USPSTP Grade D
PSA testing USPSTP Grade D


This new recommendation from America’s top agency now has the medical world in turmoil similar to the mammogram debate two years ago. But as I said before, evidence has been building that the PSA test is causing more harm than it is helping. I’ve talked with my male patients about this test for a while and now will be even more against it — but even in my own hospital we routinely perform this test as part of health packages for men, as do most hospitals. This new data will definitely be a hot topic at our next Journal Club meetings!

The sad part to this story, of course, is that there unfortunately is no excellent screening test for prostate cancer, which leaves men feeling vulnerable. In this age of “constant scientific progress”, to be told that your test is no longer considered useful is indeed unsettling. Let’s hope that the world’s scientists quickly come up with a more accurate screening test.

Finally, A Blood Test For Liver Cancer?

Click on the arrow below to listen to this podcast, or click here.


I’m very skeptical of the common practice in Chinese “health check” centers to do multiple screening tests for cancers. Many of these tests are neither specific nor sensitive enough for cost-effective screening, and most patients end up spending a lot of money on follow-up tests which prove benign. I’m not saying the concept is bad, I’m saying that many blood biomarkers are not ready for prime time. It’s really a shame, as many cancers including liver cancer are usually diagnosed too late to help the patient survive for a long time. Perhaps there’s now some hope with liver cancer, as a Chinese team has designed a blood test which may be more accurate than the common AFP test. This hopefully will turn out to be truly effective, especially for China, as liver cancer from hepatitis B is extremely common. I discuss this issue in my weekly radio broadcast on Beijing Hour; you can listen to the podcast with the above links.

nutrition milk juice drinksPaul James and I also discuss recent news stories about the questionable nutritional value of many popular milk beverages, including Wahaha’s Nutri-Express line of milk+juice combinations. I’ve never tried them so cannot comment on the taste (milk with juice?), but in general the vast majority of this class of drinks are never as nutritious as the real deal. In other words, pure milk is usually a lot better than the super-sweetened mixes, and juices in boxes are almost always super-sweetened and also have less of the original nutrients. Your grandma was right: an apple a day keeps the doctor away.

More Podcast Information

You can always listen live to my radio interview each Wednesday around 7:35am Beijing time, on the Beijing Hour program on EZFM 91.5, which is broadcast from 7-8am every weekday by host Paul James. EZFM is the popular bilingual radio station on the China Radio International network, broadcasting here in Beijing and on multiple stations all over the world, as well as live online here.

You can listen to all my previous podcasts at the podcast archive.