Q: I love nuts, but my doctor says I must avoid them because they are high in cholesterol. He’s considering whether I need cholesterol-lowering medicine.

A registered dietitian told me that nuts have no cholesterol, so now I’m confused. Do I really need to avoid nuts completely?

A: The dietitian is correct. Nuts do not contain cholesterol. In fact, studies show that walnuts, almonds, macadamia nuts and pecans might actually help protect against heart disease.

One reader reports: “Eating a handful of walnuts every day has lowered my cholesterol 25 points.” They might not work this well for everyone, but walnuts appear to be a heart-healthy snack. Just don’t overdo it on the calories.

Q: You recently responded to a college student who had genital herpes. You suggested prescription medicines like Zovirax, Famvir or Valtrex.

I am a fourth-year medical student. Let me offer my experience. I use 500 milligrams of L-lysine daily to prevent outbreaks of oral herpes (cold sores). Although I don’t have references to document this approach, I have been using it for five years with amazing success.

A: Although L-lysine might be helpful in preventing cold sores (herpes simplex virus-1), we could find no data to support its use for genital herpes (herpes simples virus-2). Until there is better research in this area, we can only recommend prescription antiviral medications for genital herpes.

Q: I am having an awful time with medications for high blood pressure. My doctor has tried me on at least five drugs. Some don’t bring the pressure down at all, while others that seem to work have side effects that make me uncomfortable.

All my doctor has done lately is increase my dose, and I feel like a zombie. Is there anything that might work and still let me live a normal life?

A: New research shows that high blood pressure is extremely common and often untreated. This condition increases the risk of stroke, kidney disease or heart attack, but you shouldn’t have to spend years with swollen ankles, dizziness or sexual side effects for the sake of blood pressure control.

Explain to your doctor how your current medicine is making you feel, and ask if you could try a different type of medicine.

We are sending you our “Guide to Blood Pressure Treatment.” Others who would like a copy should send $2 in check or money order with a long (No. 10), stamped, self-addressed envelope to: Graedons’ People’s Pharmacy, No. B-67, P.O. Box 52027, Durham, N.C. 27717-2027.

Nondrug approaches such as weight control, exercise, a high-potassium, low-sodium diet and relaxation can all be useful in managing blood pressure.

Q: My father gave me a special supplement with fish oil that he claims is essential for good health. I take it now and then but would like to know if it is safe. I am trying to become pregnant.

A: A new study in the British Medical Journal (Feb. 23, 2002) suggests that eating fish rich in fish oil reduces the risk of premature birth. Pregnant women should avoid swordfish, shark, tilefish and king mackerel, as the mercury in such fish could harm the fetus. This is not a problem with fish oil supplements.