DEAR DR. BLONZ: I am in my junior year of a nutrition and dietetics program, and I am confused as to what path I should take for graduate school. I could see myself working for a food company -- developing, testing and promoting food products, and creating and testing recipes. If I pursue that, would it be more beneficial to focus on food science or nutrition? -- S.T., San Diego

DEAR S.T.: I often receive questions from students interested in the fields of nutrition and food science. A dietetics degree (R.D.) could certainly serve you well, but seeing as you are interested in working in the food industry, a food science degree would also seem to be a logical pursuit. Along with learning essential information about the science of food production, you would be more marketable when it came time to look for a job. You might consider a grad school that has both a food science department and a nutrition department (at some universities, these departments are combined).

I would recommend you check out the Institute of Food Technologists (ift.org), the professional organization for that industry. The group is based in Chicago. IFT's website offers information about careers in the food industry. Also, consider attending one of the many trade shows put on by the food industry. This would provide you with some excellent exposure to products, approaches and opportunities. IFT has an annual meeting, but there is also the Fancy Food Show (specialtyfood.com) and a host of others.

Whatever schools you are considering, I encourage you to ask for a list of the research interests of the faculty. Academic department success relies on the strengths of its faculty, and this is a good way to see how a department is oriented. Look for a school with faculty members whose interests are aligned with your own. I wish you well with this important decision.

DEAR DR. BLONZ: Is there any value to be gained from drinking wheat grass juice? Is this a reasonable thing to do if I do not have enough vegetables in my diet? -- J.J., Berkeley, California

DEAR J.J.: Supplements are not a substitute for healthful eating. Drinking wheat grass juice will only provide a modicum of nutrients, along with some healthful phytochemicals. Aside from testimonials, there is little in the way of evidence to support its benefits.

If you try it, you will notice its unsurprising "grassy" taste. Find an organically grown product, if at all possible. Feel free to drink it if you like the taste, but it isn't a go-to product that will cancel the impact of poor food choices. Ending a cheeseburger-and-fries dinner with a shot of wheat grass juice doesn't make it all better.

Then there's the fact that these supplements are usually quite costly. All in all, I encourage you to rethink the juice and strive to eat more vegetables instead.

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: Can you help us understand the World Health Organization's (WHO) announcement on cancer and meat? Did the WHO study control for processed meats with and without nitrites? A nutritionist once told me that vitamin C blocks the formation of cancer-causing nitrosamines, and that if I choose to eat bacon, I should also have a lot of orange juice. -- M.C., via email

DEAR M.C.: One study I recall from graduate school revealed that physicians who ate more meat and consumed more alcohol had a one-third lower risk of dying in a plane crash. Does this mean it would have been beneficial to encourage doctors to grab a burger and a beer before they boarded a flight? Needless to say, we need to understand a plausible mechanism before we can give full credence to any population study.

The announcement from the World Health Organization provides useful, but not surprising, information. At the same time, it reflects problems inherent with population studies that extract and correlate data on the impact of a single class of food. With such efforts, there is no way of knowing what was in the rest of people's diets, or the general health status of the individuals from whom the data was collected.

The WHO pronouncement, which covered meats in general, came after a review of hundreds of studies, each with its own methodology. There was a comparison, on a spectrum of health statistics, between people who ate no meat and people who ate lots of it -- and everyone in between. Find a significant difference along that gradient and you have an "association" to report between the level of meat intake and the risk of disease.

Here, we must ask if the key factor is all meat, or only processed meats. Or, does meat only become an issue when paired with a less-than-optimal intake of healthful foods? Or a progressively unhealthful, more stress-filled lifestyle? Or an interaction of these and other factors? It is difficult to control for such fine points, and population studies are not able to report cause and effect.

It is predictable that, analyzing the spectrum from no- and low-meat intakes up to hefty daily doses of the stuff, a general theme would emerge that excessive meat consumption is risky business. Many news stories left off all qualifiers and simply pronounced that "meat causes cancer," period.

A healthful diet, lifestyle and attitude are powerful mitigating factors against potential negatives, but when it comes to food, there is only so much room in our stomach. If meat is on your menu, then enjoy it, keep a handle on the portion size and don't lose sight of your plant-based, whole-foods perspective.

As for your mention of preservatives, fresh meats are less risky than nitrite-preserved meat. Nitrites can combine with the amino acids in meats to form cancer-causing nitrosamines. Vitamin C can help inhibit the formation of nitrosamines, but having orange juice with bacon shouldn't be considered a fix. Routinely having fruit or berries at any meal is always a positive.

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 understand why they put vitamin D in milk, as it aids in the absorption of calcium, which is plentiful in dairy. But why do they put vitamin A in milk? What is the connection? -- R.R. San Jose, California

DEAR R.R.: Nutrients get added to foods in a couple of ways. Enrichment is the adding back of nutrients that were lost during processing, and fortification is the addition of nutrients to a food where they do not normally occur. This addition of nutrients was begun in the 1930s as a practical means to increase the nutritional value of foods, often in response to specific deficiency conditions.

Nutrients were added to foods when typical intakes of that nutrient were below desirable levels for a significant number of people. The foods chosen to be "enhanced" were those typically consumed in sufficient quantities to have the desired effect in the target populations (and not represent any danger for excessive consumption by others). The reliance was on staple foods, such as cereals, milk products and salt.

Finally, the nutrients would have to be added in a form that would be stable and could be easily absorbed. Vitamin D, and later vitamin A -- two fat-soluble substances -- were added to dairy products mainly because they were thought to be the best vehicles for these nutrients.

DEAR DR. BLONZ: I am reluctant to try shortcuts, but I wanted information on the latest product claiming to help people "lose weight without dieting or exercising." It is called chitosan, and there are videos all over the Internet and infomercials on TV. One has a person talking about taking it before a big fatty meal, and your body won't absorb the fat. -- F.S., Austin, Texas

DEAR F.S.: Chitosan is derived from chitin (KITE-un), a component of the shells of crustaceans, such as crab, shrimp and lobster. Chitosan has an ability to bind with fat in the stomach before it has a chance to be absorbed. The chitosan-bound fat travels through the digestive tract and is eventually eliminated from the body in the feces.

If there's an upside to chitosan, it's that fewer fat calories get absorbed. There are estimates that each gram of chitosan can absorb four to eight times its own weight in fat. This means that a 250-milligram capsule could prevent the absorption of 1-2 grams of dietary fat (9 to 18 calories' worth) -- assuming that the fat is in the digestive tract along with the chitosan.

The negatives are that chitosan is not selective in the fatty substances it binds to. That means that it has an equal ability to grab onto beneficial compounds such as fat-soluble vitamins, valuable phytochemicals and omega-3 fatty acids. One study found that a high intake of chitosan led to a rapid decrease in the blood level of vitamin E.

It is also plausible that chitosan could interfere with the absorption of medications where the active component is a fat-based substance. Steroids, birth control pills, hormone replacements and many cholesterol-lowering medications, for example, could be at risk.

Finally, given that the unabsorbed, chitosan-embraced fat passes into parts of the digestive tract where dietary fats rarely go, there may be side effects like discomfort, intestinal gas and diarrhea. Keep in mind that chitosan -- or any other supplement -- does little to influence healthful eating habits, which are the key to long-term success.

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.