DEAR DR. DONOHUE: I would like some information on cholesterol for people in their 80s. I am 87 and still take cholesterol-lowering medicine. My lady friend, who is my age, was told by her doctor to stop the medicine because it could do her more harm than good. Who is right? – C.F.

DEAR DR. DONOHUE: What’s the difference between good and bad cholesterol? – W.N.

ANSWER: At what age it is safe to ignore high-cholesterol foods and cholesterol treatment is a matter of heated debate. At age 70 and above, the relationship between cholesterol and heart disease is less strong than it is at younger ages. Dutch researchers report that at age 85, having low blood cholesterol does not add any more years to one’s life. It might subtract a few years.

This is predicated on the assumption that these elderly people have no previous heart disease, no artery hardening and no diabetes. Truthfully, people who do not have one or more of those diseases in later life are few.

Cholesterol is cholesterol. There is no good or bad. LDL – low-density lipoprotein – cholesterol is called “bad” because the cholesterol in it is associated with a protein carrier that takes it to artery walls and dumps it there, where, in time, it will cause blood flow obstruction. HDL – high-density lipoprotein – cholesterol is “good” cholesterol because the protein that carries it in the blood takes it to the liver, where it is degraded and disposed of.

LDL cholesterol levels lower than 100 mg/dL (2.59 mmol/L) are considered excellent and are mandatory for people with heart disease or diabetes. HDL cholesterol should be higher than 40 mg/dL (1 mmol/L). If it is higher than 60 (1.6), it is considered a protection against heart disease and artery hardening.

The newly written cholesterol pamphlet can answer many questions that people have on cholesterol control. People can order a copy by writing: Dr. Donohue – No. 201, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: My blood tests keep showing low sodium of 129 and a low BUN. My doctor has suggested no treatments other than not drinking so much fluid. Is this something I should be concerned about? – J.H.

ANSWER: Sodium is an essential body chemical that keeps hearts beating, nerves firing and blood pressure from dipping too low. A normal level is 136 to 145 mEq/L (the same in mmol/L).

Your sodium is a bit low but not dangerously so. It might be falsely low. High amounts of fat and protein in the blood can produce a falsely low reading.

Excessive sweating, diarrhea, diuretics (water pills), a low level of an adrenal gland hormone, excessive water drinking, a low thyroid hormone level and a failing heart can yield a low sodium value.

You feel fine. You have no symptoms to indicate that you have any of the above illnesses. It is unwise to treat a low sodium value when a patient has no symptoms and no illness that lowers sodium. Symptoms of a sodium deficit include nausea, lethargy and headaches. At very low levels, mental confusion is a salient symptom, and at even lower levels coma can ensue.

BUN – blood urea nitrogen – is a measure of kidney function. High numbers indicate the kidneys are not working. Low numbers are seen when people eat a very low-protein diet or a very high-carbohydrate diet. Liver failure and drinking large quantities of fluid are other causes of a low reading. Again, without symptoms and without signs of any illness, a low value is not usually a matter of concern.

DEAR DR. DONOHUE: I have a slightly high cholesterol count. My doctor has not suggested any medicine. I would like a list of foods that lower cholesterol naturally. Thank you. – G.C.

ANSWER: You’re welcome.

Oats, barley, eggplant, soy protein, beans, cauliflower, broccoli, carrots, oranges, apples, pears, whole grain breads and cereals, fish and nuts can bring cholesterol down. So can olive, corn, sunflower seed, canola and soybean oils.

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.