DEAR DR. DONOHUE: Why? Why do you reject out of hand any cure or treatment that has to do with vinegar? I have tried in vain to tell you about the effective treatment of dandruff with vinegar. You’ve ignored me. You recently rejected apple-cider vinegar as a cure for toenail fungus. I find that baffling. Apple-cider vinegar kills all types of fungus. Why do you withhold this information from your readers? Can’t you hold the slightest possibility that AC vinegar might be a miracle treatment? I have also used it on my son for ringworm many times, and he wakes up the next morning with no trace of ringworm. It steams me to see you denying this home remedy. – An Irate Reader

ANSWER: Be unsteamed, Irate. I am giving you a place in the sun.

Many have written to me about the wonders of vinegar, and they usually specify apple-cider vinegar. I don’t know why. All vinegars are dilute acetic acids with a concentration of acid between 4 percent and 7 percent. Vinegars can be made from apples, grapes, barley, oats, beer, wine, potatoes, rice and sugar. After those substances are treated with yeast to produce alcohol, the bacterium acetobacter is added, which interacts with oxygen to convert the alcohol to vinegar.

People say that vinegar can do all of what you say it can, and many add that it can lower cholesterol, cure allergies, serve as a tonic for arthritis and clear up sinus infections.

Vinegar is an excellent flavor-enhancing substance. It preserves foods by pickling them – meats, fish, fruits and vegetables. It can kill some bacteria. That’s what gives it its preservative power. It’s suggested for the pain of a jellyfish sting.

However, I can’t find any medical proof that the claims to its healing powers are substantiated. Would you want the FDA to allow on the market anything that has not been subjected to stringent investigations?

It’s a free country, and people can do what they want, but I must have scientific proof of a substance’s effectiveness and safety before endorsing it.

DEAR DR. DONOHUE: I am a woman, 42 years old, still fighting a losing battle with acne. I believe I have used every treatment available. Now my doctor suggests taking birth-control pills. I have no objection to taking them because I have four children and don’t want any more. But what has the birth-control pill got to do with acne? – J.K.

ANSWER: Male hormones, to a large extent, are to blame for acne. They foster the production of skin oil. Women do make male hormones – granted in smaller amounts than men, but enough to cause some women to have acne. The oil plugs the ducts of oil glands that empty onto the skin. The glands fill up with oil. Bacteria love to feast on it. They do, and the bacterial population grows. Soon pimples are born.

The birth-control pill counters the effect of male hormones on oil glands. Acne doesn’t disappear overnight when you begin birth-control pills. They don’t do a thing for the pimples that have already broken out. You won’t see a big difference until four to six weeks so be prepared for a little wait.

You’re not the only adult woman to battle acne well past adolescence. Some women have to contend with it for most of their lives.

DEAR DR. DONOHUE: My 8-year-old grandson takes Ritalin for attention-deficit disorder. What is this drug doing to his brain? Giving a mind-control drug to such a young child sounds dangerous to me. What are the consequences of this? – C.N.

ANSWER: Ritalin is not a mind-control drug. It helps a child whose brain is bombarded with distracting input signals to ignore those signals and concentrate on the task at hand. It helps such a child stop fidgeting and reduces impulsive actions.

One reason for giving the medicine to a child is to provide that child with a chance to learn without the distractions that disrupt his or her focus. In time, the child is often able to dispense with taking the medicine.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from

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