Vitamin D doesn’t just come from sun

Dear Drs. Donohue and Roach: I take a vitaminDevery day, but I also put sunscreen on my exposed skin when I go outdoors. Won’t the sunscreen interfere with the effects of the vitamin D? — L.P.

Low vitamin D is increasingly being diagnosed, and has been implicated in many conditions. What is absolutely clear is that vitaminDis necessary for proper bone health, and many Americans, particularly those who live in the northern two-thirds of the country (and all Canadians!) are at higher risk. Darkerskinned people also are at higher risk for low vitamin D levels, and low vitamin D has been shown to be a reversible cause ofweakness in the elderly.

Preliminary studies have linked lowvitaminDto cancer, but it is too early to say whether replacing vitamin D will reduce cancer risk.

Most peoplemake their own vitamin D with a short period of sun exposure to their face and hands, and sunscreen does indeed prevent the skin from making the active form of vitaminDin sunlight.

Since you’re taking supplemental vitamin D (in the form of vitamin D-3), the sunlight isn’t necessary. You are, in effect, bypassing the skin’s involvement.

Dear Drs. Donohue and Roach: I take methotrexate and Remicade for rheumatoid arthritis. Both the doctor and the pharmacist have told me not to drink alcohol with these medications. Neither one could tell me why alcohol is contraindicated. Recently, a nurse told me that moderate drinking is OK. I am not a big drinker, but occasionally I enjoy wine with a dinner out. However, I don’t want to do anything that will affect the good results I am getting. Do you know why alcohol is prohibited?— C.M.

The concern is damage to your liver, which is the major toxicity for methotrexate and is possible with Remicade.