Archive 2006 2007 2008 2009

Q. Do you recommend over-the-counter NSAID patches and gels for pain? Are they less likely to cause side effects than pills?

A: We don’t recommend them, because the evidence of benefit is not clear.

NSAIDs (nonsteroidal anti-inflammatory drugs), such as aspirin and ibuprofen, are usually taken orally but also come in patches, creams, and gels. The over-the-counter products (such as Aspercreme and Arthricream) are less likely than pills to cause gastro-intestinal bleeding, but there’s little evidence they are effective pain relievers. Their active ingredient is often methyl salicylate or trolamine salicylate, both related to aspirin. It’s not certain how much is absorbed through the skin. If well absorbed into the bloodstream, large amounts of the active ingredient would produce relief, but also the same side effects as pills; if not well absorbed, they would provide little or no relief.

Studies of topical NSAIDs, usually short and limited, have yielded conflicting results. A review in the British Medical Journal in 2004 concluded that topical NSAIDs do not control arthritis pain well.
Topical products with ibuprofen (or closely related ingredients) are sold by prescription, and some doctors recommend them for people who cannot take NSAIDs orally. As with the OTC products, it’s not clear how much is absorbed through the skin.

All topical NSAIDs can cause skin irritation.

Q: Is the vitamin D you get from being in the sun or a tanning salon better than what you get from a supplement?

A: No. Whether you get vitamin D from sun exposure or from supplements, blood levels of the active form of the vitamin rise similarly, and other effects in the body are the same. Still, some websites claim that it’s better to get vitamin D from the sun or tanning beds. Not surprisingly, many of them sell or promote tanning beds.

Vitamin D is unique in that your skin manufactures it when exposed to the sun’s ultraviolet (UV) rays. Exposing your arms and legs to the sun for just 10 or 15 minutes two or three times a week can produce substantial amounts of D, though this depends on the time of day, season, weather, how far north you live, how dark your skin is, and your age; older people produce less D from the sun. Few foods provide D, so it’s hard to get adequate amounts from food alone—especially not the levels many experts are now recommending for bone health and a variety of potential benefits.

Since exposure to UV radiation, whether from the sun or tanning beds, can cause skin cancer, it’s safer to get vitamin D from supplements. One exception: if you have certain rare intestinal absorption problems, you may not be able to absorb oral vitamin D well and may need to get it by injection.

Despite claims made by the tanning industry, tanning-bed sessions provide much more UV and expose more skin surface than is needed to produce adequate vitamin D. Maximum possible synthesis of D occurs before the skin reddens, and thus longer exposures add nothing to vitamin D stores, according to a review in the Journal of the American Academy of Dermatology in 2005.

And by the way: When you read that humans are “designed” to get their D from the sun, remember that this made sense hundreds or thousands of years ago when people rarely lived past 40, usually not long enough to develop skin cancer.

Q: Are headstands safe?

A: Not always. Aside from the more obvious risk of neck injury, the yoga headstand posture causes spikes in intraocular pressure (IOP), the pressure of fluid in the eye. A study in the American Academy of Ophthalmology in 2006 found that when yoga practitioners did headstands, their IOP doubled, on average—with the increase occurring as soon as the position was assumed and the pressure returning to near-normal immediately afterward. Other papers have found that IOP increases up to fourfold.

While temporary spikes in IOP are nothing to worry about in healthy eyes, there is concern that they can, over time, progressively damage eye tissue and promote or worsen glaucoma and some other eye conditions. Thus, anyone with glaucoma or ocular hypertension should avoid headstands. To be on the safe side, people with poorly controlled hypertension should also avoid them. Older people and anyone at risk for glaucoma should get a full eye exam before doing headstands.

Some people have heartburn after doing headstands. There are no studies to confirm this, but the position could aggravate heartburn by allowing stomach acids to back up into the esophagus. People who tend to get heartburn should not even lie down after meals, let alone do headstands.

Q: What is UHT milk? Does it contain fewer nutrients than regular milk?

A: Ultra-high temperature (UHT) milk is heated to at least 275° F for about 2 seconds, destroying virtually all bacteria, and then packaged in special sterile containers. This milk will last unopened at room temperature for months. Once opened, it has the same shelf life as regular pasteurized milk, which is heated to 160° F for 15 seconds.

The UHT process reduces some B vitamins and vitamin C (not significant in milk anyway). Vitamins D and A (added to nearly all milk) and minerals are not affected. This “long-life” milk has been popular in Europe for years, where it saves millions in refrigeration costs. The milk may taste a little “cooked,” but many people learn to like it.

UC Berkeley Wellness Letter, May 2009