This article is the archived version of a report that appeared in July 2009 Consumer Reports magazine.

You wanted to know . . .

Will I damage a car that's supposed to use premium gas if I fill it with regular?

Thomas Sklarski
Garfield, NJ

If your owner's manual recommends, but doesn't require, that you use premium gas, you can usually use regular safely. If necessary, the engine's computer-control system will adjust the ignition timing to compensate for the lower octane of regular gas. That could result in a slight decrease in power and fuel economy in high-load conditions, such as when you're accelerating hard or towing, but you probably won't notice it. If the manual says premium is required, use only premium.

Is it safe to use an indoor electric grill whose nonstick coating is flaking off?

Thomas Hiday
Bardstown, KY

No. The flaking might be caused by uneven heating, which in some pans could accelerate emissions of perfluorooctanoic acid. That chemical can cause cancer and birth defects in animals and might pose similar risks in humans. What's more, your food is more likely to stick and even burn. Don't put an empty nonstick pan over very high heat, and when you cook with a nonstick pan or appliance, use ventilation. Call your public-works department to find out how to dispose of your old grill.

What can you tell me about "virtual credit cards"?

Frank Kingston Smith
Scottsdale, AZ

Issuers including Bank of America, Citi, and Discover offer those cards, which are meant to thwart thieves when you shop online, by phone, or by mail order. For no extra charge you sign up online for a virtual number that replaces your card number. When you shop, you receive a randomly generated 16-digit number. Depending on the card issuer, that number is valid for one or more transactions. Note that you can't use a virtual card for purchases requiring you to show your actual card.

What foods besides broccoli lower the risk of prostate cancer?

Paul Coon
Apopka, FL

Broccoli has a high concentration of cancer-fighting sulforaphane, as do other cruciferous vegetables, including brussels sprouts, cauliflower, and kale. That group of vegetables has also been associated with a lower risk of breast cancer, giving women even more impetus to eat crucifers. Foods that are rich in the antioxidants lycopene (apricots, tomatoes, and watermelon) and quercetin (apples, beans, and onions) might also help fend off prostate cancer.

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