Question: My children are grown now, but back in the late 1970s, I would mix their baby formula with boiled water and put it into the plastic liners of disposable baby bottles, which I now know contain bisphenol A (BPA). My children haven't had any problems, but I am still concerned about the danger I've put them in. Is there anything they need to know to minimize their cancer risks? — Maria, Alameda, Calif.

Answer: Put a hold on the guilt. At this point, for most of us, BPA is the proverbial spilled milk (but don't give your old plastic bottles to anyone you like), and it is likely not the only environmental carcinogen to which you and your children have been exposed. (In fact, receipts printed on thermal imaging paper — like most restaurant receipts — are a more potent source of BPA.) It doesn't mean they're doomed. Chemicals found to be carcinogens don't always cause cancer, and you can always minimize risk by making a few smart lifestyle choices known to protect against the disease (including never drinking anything from polycarbonate plastic again).

Avoid other known carcinogens, including tobacco smoke and an overdose of ultraviolet light.

Eat five to nine servings of vegetables of every hue daily. Include cruciferous vegetables (such as broccoli and cabbage), which may help prevent breast cancer, and red-orange vegetables, which contain lycopene, a nutrient that's linked to both prostate- and breast-cancer prevention.

Get enough D. If you don't consume enough foods containing vitamin D (most people don't), then take a D supplement (1,000 IU if you're under 60; 1,200 IU if you're over).

Avoid taking any non-carbon receipts (from gas stations, restaurants, etc.) that you don't need.

Take up to 200 micrograms a day of selenium, a trace mineral that plays a big role in helping your body detoxify harmful chemicals.

Walk, run, bike, skateboard, whatever raises your heart and breathing rates and produces a little sweat. Do it for 30 to 60 minutes most days of the week.

Question: Why do you recommend Beano without reservations? For those of us who are allergic to penicillin, the fine print on the packaging says we shouldn't use this product. — Anonymous