DEAR DR. BLONZ: I ate great and was active in college and grad school, but since then, I have been working on starting a business and that's been the main focus of my life. I have no time to exercise, with the exception of a bit of walking. I am constantly eating fast-food burgers and fried foods. I don't have time to cook, so I opt for what's convenient. I usually rush out in the morning with very little to eat (maybe some cereal), then I don't eat again until I come home eight or nine hours later. At home, I make telephone calls and then eat my dinner at about 11 p.m. or later.

I am still young, so I am hoping that my body will be forgiving during this investment phase of my career. My girlfriend is quite concerned, and it is affecting our relationship, so I wanted to ask: How dangerous is what I am doing? -- S.T., San Francisco

DEAR S.T.: It must be difficult for one who knows better to find himself totally immersed in a lifestyle that is far afield from previously healthful habits. How dangerous, you ask? That's a difficult question to answer with certainty, because much depends on other elements, such as your age, weight and any pre-existing risk factors.

Even without knowing the other elements, I would certainly question the wisdom of the torrid lifestyle you've described. The unbalanced fried-food diet, the lack of exercise and the apparent high stress level are definite benchmarks of a road to ruin. Is there an end in sight? For your sake, I hope so.

I apologize if this comes across as lecturing, but your priorities need to be re-examined. There are remedies; all you need is the wherewithal to shift a few items on your schedule.

Most markets offer a wide variety of fresh, whole foods, as well as a host of other culinary delights and options far beyond those at a quickie restaurant. You can keep dried fruits, nuts and seeds in your desk, and you might see if there is room for a refrigerator in your workspace. If so, you can stock it with healthful snacks such as fruits, vegetables, yogurt and juice. This would make you less of a slave to vending machines and fried, fast-food fixes.

For your food outside of work, I would suggest sprucing up your breakfast. Get a higher-fiber cereal, and make sure you always have either fresh fruit or juice with your meal. I know that you are strapped for time, but you might consider taking a cooking class. This would help you learn to cook in less time, using healthier ingredients, and you could even take the leftovers to work the next day!

Other important points are to devote more time to physical activity and get the sleep your body needs. You may find that your daytime productivity improves. I encourage you to make these changes now, and enlist your girlfriend to help keep things on course. The big risk is that a lifestyle of unhealthful habits has a way of setting itself up on autopilot and becoming your long-term "normal."

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: I drink lots of tea, mostly green and black (decaffeinated) with my meals. I am a vegetarian, and a nutritionist was concerned that I may be "losing" protein because the tannins in tea bind up the protein in my food. Is it true that tannins bind up proteins? Are there any teas that I would do better with? -- W.S., Madison, Wisconsin

DEAR W.S.: Tannins are naturally occurring plant substances that belong in the family known as the polyphenols. Certain tannins can indeed react and bind with proteins, but it should not be a concern since they tend to spread out their binding to other substances as well.

As teas go, black and oolong do contain relatively high levels of tannins, and green tea contains lesser amounts. To have a tea with low or no tannins, you will need to find one that is not made from leaves of the traditional tea plant (Camellia sinensis).

Protein can be affected by tannins, but a few cups of tea a day will not produce a worrisome protein-depleting effect. Most people -- including vegetarians -- eat more protein than their bodies require. (An interesting historical aside: Tannins derived from trees have long been used to react with the proteins in animal hides, and this process is integral to the "tanning" of hides into leather.)

Tannins can also affect the absorption of minerals such as iron and calcium, and this might be of greater concern. If you tend toward iron-deficiency anemia, it makes sense to avoid drinking a high-tannin tea with a key iron-rich meal. Calcium is less of a concern because there tends to be more of it in foods than there are tannins in tea.

For most people, an occasional loss of a few milligrams of an otherwise plentiful nutrient should not be a great concern. Tea has a number of healthful benefits, so enjoy.

DEAR DR. BLONZ: Can you explain the nutritional roles of zinc and copper? I heard it is not OK to have these at the same meal. -- U.A., San Francisco

DEAR U.A.: Zinc plays a role in many enzymes, including those involved in detoxification, sex-hormone production and wound healing. It is also involved in taste and smell. Copper helps in the formation of red blood cells, is essential for normal hair and skin, and is needed for normal respiration and the production of certain antioxidant enzymes.

Both are essential nutrients, and there is no problem taking recommended amounts at the same time. I think the source of your concern is based on the fact that too much zinc can deplete the level of copper in the body; likewise, if copper intake is excessive, the level of zinc can suffer. This antagonism only comes into play if there is an imbalance.

The take-home message, at least with zinc and copper, is that we shouldn't overdo it unless there is a medical reason to do so. At present, the Daily Value for zinc is 15 milligrams and the tolerable upper limit is 40 milligrams per day. For copper, the Daily Value is 2 milligrams and the tolerable upper limit is 10 milligrams per day. These figures are for adults 19 years of age or older. (For those not familiar with this term, "tolerable upper limit" is the highest level of intake that is likely not to pose any risk of adverse health effects in almost all individuals.)

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: After my last health exam, I've decided to make the move to a vegetarian diet. I currently eat pretty well, having meat no more than a few times a week and fish at least once. I have heard many things concerning the lack of protein and of one kind of vitamin B in typical vegetarian diets. Do these concerns have any validity? Should I be taking a certain supplement in addition to my multivitamin? -- H.M., San Diego

DEAR H.M.: Health statistics for groups of vegetarians include lower rates of heart disease, obesity, obesity-related diabetes, colon cancer, lung cancer, breast cancer, hypertension, osteoporosis, kidney stones, gallstones and diverticular disease. Though some gains are connected to the lifestyle that's frequently adopted along with the new eating habits, these findings are certainly impressive.

Protein is rarely a problem for vegetarians eating a varied diet. However, if you are going to adopt a vegan diet -- that is, one with no animal products at all (no meat, fish, dairy or eggs) -- sources of certain essential nutrients will be harder to find. These nutrients include calcium, iron, zinc, vitamin B12 (the "B" you were referring to), vitamin D and riboflavin. You can get all of these nutrients in foods, but if you want a supplement for added insurance, these nutrients are the ones to look for. Again, if you continue to eat dairy and eggs, this is less of an issue.

In general, becoming a successful vegetarian means learning which foods are required for a complete diet. These food selections and combinations become very important -- especially with children and pregnant or lactating women. There are resources you can consult for more specific information. Nutritiondata.com provides a convenient nutrition breakdown of many foods, and it can suggest those that are rich sources of specific nutrients. Other online resources include the Berkeley Wellness Letter, tinyurl.com/le7r7l9, and the National Institute of Health MedlinePlus page: tinyurl.com/kwm6j3.

DEAR DR. BLONZ: Please don't be offended, but I am curious about where you went to school and what you studied. You are called a nutritionist, but many people use this title. Do you have a degree in nutrition? Are you a registered dietitian? -- S.S., Phoeniz

DEAR S.S.: It's never a problem to answer these questions. You are correct that many call themselves nutritionists; unfortunately, there is little regulation associated with the term's use. It is definitely "buyer beware" when seeking advice.

I did my undergraduate study at the University of Wisconsin at Madison, where I studied psychology, and my graduate degrees are from the University of California at Davis. I earned a master's degree in nutrition, working on a problem involved with food toxicology. My doctorate was also in nutrition, and I did research on the role of insulin in the development of obesity. I am not a registered dietitian. There is a brief bio online at blonz.com/bio.htm.

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.