We tried a treatment from your column for nighttime leg cramps. My husband used to get them frequently and would have to walk them off while in pain.

He read that taking mustard would alleviate them, so he tried it. Now when he gets leg cramps at night, he takes his mustard and they go away quickly.

He keeps a few individual packets of mustard in the bedroom. He thought it was just an "old wives' tale," but now he's a believer.

We are delighted to learn that yellow mustard has helped relieve your husband's leg cramps. A retired pharmacist told us about this remedy nearly six years ago: "A friend of ours uses plain mustard for leg cramps. She swallows a teaspoonful of mustard to relieve the pain. This home remedy works so well for her that she carries packets of mustard wherever she goes."

Since then we have heard from many folks who use yellow mustard to relieve leg cramps. Although there is no science, we suspect that turmeric, which gives mustard its yellow color, may have a beneficial effect.

Many readers also report success with low-sodium V8 juice, magnesium or a bar of soap under the bottom sheet.

My mother-in-law uses castor oil for bruises. At Christmas, my sister-in-law sat down in a heavy, old rocker-recliner chair. It went crashing to the floor, and one corner landed right on top of my mother-in-law's foot.

My sister-in-law was dazed and took a moment to get up, which meant my mother-in-law's foot was trapped under the chair for a few seconds. She was screaming!

We all urged my mother-in-law to go to the hospital to make sure no bones in her foot were broken, but she refused. Instead she slathered the top of her foot with a generous amount of castor oil. She said that castor oil applied immediately to a bump reduces swelling and prevents bruising. I didn't believe it until the next day when I saw that her foot was fine! I don't advocate castor oil for serious injuries, and I do think my mother-in-law should have had her foot X-rayed, but for minor accidents, it works great!

Castor oil contains ricinoleic acid. This compound has both pro- and anti-inflammatory effects (European Journal of Pharmacology, Oct. 27, 2000). Regular topical use seems to improve pain tolerance, but no one has studied an anti-bruising effect.

You had a question from parents concerned about their son using more than three big bottles of mouthwash in a week. Shame on you for soft-pedaling the use of Listerine. My dad dried out and then restarted on mouthwash. Alcoholics lie and deny.

Thanks for your concern. The parents were convinced their son was ingesting mouthwash, since he had already gone through detox once. They wanted to know the consequences of drinking Listerine. Original formula Listerine contains 26.9 percent alcohol. Clearly, anyone using five liters of Listerine in eight days needs professional help.

I just read that grapefruit increases the risk of breast cancer. What gives? I always thought fruits and vegetables prevented cancer.

One study showed that grapefruit raises estrogen levels in postmenopausal women. Higher estrogen is associated with greater risk of breast cancer. Another study reported that women who regularly ate grapefruit were 30 percent more likely to be diagnosed with breast cancer (British Journal of Cancer, July 10, 2007). Other researchers have found no connection between grapefruit consumption and breast cancer (British Journal of Cancer, Jan. 8, 2008). Grapefruit interacts with hundreds of medications and can increase the risk of side effects.

In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of this newspaper or e-mail them via their Web site: peoplespharmacy.com.