THANKS FOR ASKING

Virginia Responds to Reader Questions

Q: In the last issue of the Hopkins Health Watch, you mentioned that dry cleaners are now adding fragrance to their cleaning fluids. My dry cleaner recently started advertising “organic dry cleaning.” It sounds too good to be true.

A: Yes, it is too good to be true. Technically speaking, if you’re a chemist, anything with a carbon chain is “organic,” which would make gasoline, cyanide and deadly nightshade organic. It’s a semantic lie, and intentionally deceptive marketing, since most of us assume that something labeled “organic” is harmless to our health and to the environment. The so-called organic dry cleaning chemical is DF-2000, which the EPA lists as a neurotoxin, and as a skin and eye irritant. In terms of toxicity, it’s only marginally better than the standard dry cleaning solvent perchloroethylene, or perc, and it’s just as harmful to the environment.

Q: I heard that the sweetener xylitol, which you have recommended [for humans] in the past, can poison dogs. Is this true?

A: Yes, xylitol can poison dogs. It’s a mystery why humans can ingest it with no side effects (except gas in some susceptible people), and yet it can make dogs very sick. Symptoms can include vomiting, diarrhea, loss of coordination and seizures. Other people foods that can poison dogs include onions, raisins and chocolate.

Q: You introduced a new vitamin D blood spot test a few weeks ago and gave recommendations for taking supplements. But do we have solid evidence that supplements really take the place of getting out in the sun?

A: That’s a great question. We really do need more research showing that vitamin D supplements ward off the long list of health problems caused by vitamin D deficiency. So far, most of the research just confirms that people with low vitamin D levels have a much higher risk of various cancers, osteoporosis, heart disease and multiple sclerosis, for example. But we can’t automatically assume that supplements will have the exact same effect as sun exposure—a lot goes on between the time the sun’s rays hit the skin, the conversion to vitamin D occurs, and its entry into cells. We do know that supplementation prevents the bone disease rickets and helps increase bone density, but we do need clear, consistent research showing benefits in the other diseases related to deficiency. I believe odds are good that vitamin D supplementation will help prevent the deficiency diseases, but that it’s also wise to get an average of 15 minutes of sun exposure daily if and when you can.