What is the nutritional value of one of my favorite vegetables, zucchini?

ANSWER - Zucchini is high in potassium; one cup has the same amount as six ounces of orange juice, another more well-known source. It also contains some iron and B vitamins. Zucchini's greatest strength may be that it is low in calories, so if you prepare it without adding too much fat you can eat it with impunity. As a cooking method, steaming is superior to boiling, which may cause the vegetable to go limp. Another way to keep it crunchy is to sautee it quickly in a little oil. To vary the theme, first brown some garlic and then mix in lightly cooked mushrooms and zucchini for a fast stir-fry. For extra dash, season with hot-pepper oil and a touch of teriyaki sauce.

QUESTION - I play tennis three times a week and ride my bike at least twice a week. I feel good about getting all this exercise but I have no idea how many calories I'm actually burning. Can you tell me?

ANSWER - It's impossible to give you an exact figure without knowing either your size or the vigor with which you pursue these commendable activities. Larger, heavier people burn more calories than smaller, lighter ones, since they are moving around more when they exercise, just as you use more energy lifting a sofa than a chair. And, of course, a short, slow bike ride will burn fewer calories than a long, vigorous one.

To give you a general idea, though, a person weighing 125 pounds uses about 335 calories in an hour of tennis, while a 150-pound individual would burn about 65 calories more in the same time period on the tennis court. As for biking, at a cruising speed of 5.5 miles an hour, the 125-pound person would burn about 250 calories and the heavier individual about 350. But at the faster pace of 13 miles per hour, the lighter biker would burn about 535 calories and the heavier one 640.

Clearly, both tennis and biking are excellent forms of exercise. Keep up the good work!

QUESTION - I have a recipe for molasses cookies that I just love. Am I right in thinking molasses is good for you nutritionally? What exactly is it anyway?

ANSWER - Molasses is what remains after most of the sugar crystals are removed from the concentrated juices of either beet or cane sugar. It's primarily sugar - about 70 percent. The rest is water (about 25 percent) and mineral ash (a maximum of 5 percent).

Besides calories, molasses does contain some nutrients, including iron and some calcium. The amount varies by type. Light molasses has less than a gram of iron per tablespoon, while blackstrap molasses contains more than 3 grams, which is 16 percent of the recommended daily allowance. Blackstrap molasses also contains 137 milligrams of calcium per tablespoon, about what you'd get in a half cup of milk, whereas light molasses has just 53 milligrams. In past times, blackstrap molasses was an unpalatable component of numerous folk recipes, and many a "peaked-looking" child was made to choke down spoonfuls of it. These days, however, most of it is used in rum production.

QUESTION - My teen-age son is into athletics. Recently he came home from the health-food store with bee pollen, which he seems to think will improve his performance. What's your opinion?

ANSWER - There is no scientific evidence that bee pollen is of any use to anybody but bees. When broken down to its components, it contains simple sugars, fatty acids, amino acids and glycerol - nothing magical to give athletes special powers. The rumor that it enhances performance has never been proven. Then there's the safety issue. Some individuals, who are allergic to specific pollens, have developed severe reactions after ingesting that pollen. Another bee-related product, royal jelly, is also sold in some health-food stores. As with pollen, no usefulness to humans has ever been demonstrated.

You might gently point out to your son that buying such products is not the best use of his (or perhaps it's your) money. When it comes to sports, practice, not potions or powders, makes perfect.

QUESTION - Are Teflon-coated pans safe, even if they chip?

ANSWER - Yes. The safety of Teflon has been examined from two different perspectives, and seems to offer no health threat. It's true that sharp kitchen tools can chip Teflon and therefore aren't recommended for use by manufacturers. But tiny particles that might chip off actually pass through the body unchanged. Theoretically, a second potential danger might result from exposing the coating material to high heat for prolonged periods. Again, studies done nearly 30 years ago failed to demonstrate any problem with that, either. At high temperatures, the resin does decompose. However, the toxicity of any fumes that arose was less than that given off by ordinary cooking oils, among them both corn and peanut oil. And further studies indicated that the safety of the coating does not appear to decline with age.

Teflon, which is a tough, nonporous resin, was actually discovered by accident in the late '30s and first used as a durable component in radar systems.

QUESTION - Is there any evidence that eating too much sugar causes diabetes?

ANSWER - Studies have failed to show a relationship. On the surface, such a link might seem logical, since with diabetes the ability to regulate blood sugar is diminished. Nevertheless, theories linking sugar intake to development of diabetes haven't stood the test of scientific inquiry. The suggestion that a small proportion of the population may be "carbohydrate sensitive" has never been proven. And although rats on high-sugar diets will develop diabetes, this observation hasn't been made with humans. For one thing, people handle fructose - one of the two sugars in sucrose - very differently from the way rats do. Comparisons of sugar intake and diabetes rates in human populations also fail to indict sugar. In fact, studies show an inverse relationship between carbohydrate intake, including sugar, and diabetes risk - meaning that as carbohydrate consumption goes up, risk actually goes down.

There is also the question of a link between sugar and obesity, and a consequent rise in likelihood of developing the disease. Yet sugar itself doesn't seem to exert any influence. Certainly it's true that obesity raises risk of developing diabetes, which doubles with every 20 percent of excess pounds. But evidence even suggests that overweight people tend to consume less sugar than average.

The long and short of it? There are many reasons to limit the amount of sugar you eat, but hope of avoiding diabetes is not among them.

1991, Washington Post Writers Group