DEAR DR. BLONZ: I am a computer engineer and I was fortunate to get a job just out of college. It's a great job, but I spend most of my time working in a cramped space. My concern is that I always eat high-calorie convenience food when I am working, such as pizza, hot dogs and hamburgers. I do like the stuff, but I don't want to be headed down a bad road. What should I add to help prevent chronic diseases? -- I.F., San Jose, Calif.

DEAR I.F.: When young, we have a resilience that allows us to feel that we can eat just about anything and not suffer ill effects. Unfortunately, continued imbalances and abuses over the decades do add up, and by the time we reach our later years, we have to live with the cumulative effects.

There is often a covert aspect to chronic disease. A perfect example of this is hypertension (high blood pressure) where, with the exception of elevated numbers on a blood pressure reading, there can often be no signs or symptoms until the disease's damage is done.

Everything we eat does not have to be a paragon of healthfulness. My approach has always been that you can eat most things as long as the rest of your diet fills in gaps and makes things "whole." Add to this a healthful lifestyle and you can have it all.

But now let's pose a few questions. When building or working on a computer, would you choose substandard components? Would you run a computer in an environment where vibration, dust or power glitches could interfere with the operation of the unit? And finally, would you rely on an operating system that was full of buggy subroutines?

The computer programmer adage "garbage in, garbage out" is akin to dietary dogma "you are what you eat," both reflecting that we are only as good as what we put into our systems.

I encourage you to take a close look at the totality of what you eat, as well as what you are not eating. If your workday is limited in its food options, help your situation by starting the day with a high-fiber breakfast cereal with fresh fruit. Try to have a big salad or fresh vegetables with your lunch, but if that's not feasible, be sure to have those greens with dinner. Keep some nuts and dried fruit at your desk for a snack. Stash some yogurt in the office fridge. If possible, go for a brisk walk during a break -- up and down the stairs or around the block, if that's all that's available. Tweaks such as these could turn those workday fast foods into a minor player in your overall diet and provide greater distance between yourself and the risk of chronic disease.

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: Please tell me what you think of the following statements describing the benefits of waterless cookware. These were the selling points at a cookware party where the salesman made a presentation in the hopes of signing everyone up. The promotional claims were: 1. When cooking vegetables in water, all or most of the nutrients are depleted. 2. Pans made of aluminum or Teflon, or enamel-coated pans, have been proven to cause disease. 3. Cooking with oil can cause disease. How truthful was this salesman? -- S.C., Sun City, Ariz.

DEAR S.C.: These statements are examples of playing fast and loose with the facts in the hopes of getting customers to sign on for the product -- a technique that can give salespeople a bad name. Perhaps he was just repeating what he was told by his trainer, but whatever the source, those statements are definitely off the mark. There is probably nothing wrong with the cookware, but your purchase should be made with your eyes open. Let's look at the individual assertions:

1. When cooking with water, all or most of the nutrients are depleted.

False. While all forms of cooking will deplete some nutrients, the actual nutrient losses depend on many factors, including temperature, cooking time, type of food, size of the pieces and how much water is used (if any). The amount of loss will also vary with the type of nutrient. Water will deplete some of the water-soluble vitamins, but only if the cooking water is discarded. Heat, regardless of its source, can affect the fat-soluble vitamins, vitamin C and thiamin. The most stable of the nutrients are the minerals, and unless a large amount of water is used with food that has a small particle size, and the water is discarded, these nutrients will remain in the finished product. 

2. Cooking with pans made of aluminum or Teflon, or enamel-coated pans, has been proven to cause disease.

False. There is no evidence that Teflon or enamel-coated pans cause disease. But what about aluminum? It is true that there is a higher than normal amount of aluminum in the brains of individuals with Alzheimer's disease, but there is no evidence that aluminum cookware is a part of the problem. A study published in the journal Food Additives and Contaminants reported that even if you were to take an entire day's food supply, store it in aluminum containers and prepare it in aluminum cookware, the daily aluminum intake would be approximately 6 milligrams a day. Compare this with the Provisional Tolerable Weekly Intake of 7 mg of aluminum per kilogram body weight (established by the Joint FAO/WHO Expert Committee on Food Additives). This is the equivalent of 68 mg of aluminum per day for a 150-pound adult -- meaning that our hypothetical 6 mg per day is well within the acceptable limit.

3. Cooking with oil can cause disease.

False. But of all the statements, this one at least has a modicum of truth. Cooking with oils is not inherently dangerous, but elevated intakes of certain fats are associated with an increased risk of disease. I would stay away from any source of trans fat, and I would avoid mistreating cooking oils by overheating them or failing to store them properly. But assuming you have an otherwise healthful diet, fats are not to be feared. In fact, they lend wonderful tastes and textures to the foods we eat. And isn't enjoyment what eating is all about?

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: Could you please tell me about Crohn's disease and how vitamin B-12 might be involved? I have needed occasional shots of B-12 before, and now my close friend has been diagnosed with Crohn's disease and will need regular B-12 shots. What are these shots for? Supposedly, they give energy, but I want to know more. -- G.C., San Jose, Calif.

DEAR G.C.: Crohn's disease involves a chronic inflammation of the intestines and it exists in varying levels of severity. Researchers have yet to unravel the cause, and, unfortunately, there is no cure at the present time. However, new medications and therapies are helping provide some relief. The National Library of Medicine has an information page (tinyurl.com/4f5xgw4), and there is more available from the Crohn's and Colitis Foundation of America (ccfa.org).

Vitamin B-12 is essential for the creation of cells, and is present almost exclusively in foods of animal origin. It's prevalent in most meats (especially organ meats), dairy products (especially yogurt) and eggs, and can be added to certain vegetarian foods.

It takes two separate components for vitamin B-12 to be absorbed into the body. The first component is the vitamin itself, ingested from foods or supplements. The second is a protein manufactured by the body, referred to as the "intrinsic factor." This factor bonds with the vitamin and serves as an essential escort to allow passage through the absorptive surface of the intestines. Without its intrinsic factor, little if any dietary vitamin B-12 gets into your system.

People who have ailments or injuries that affect the absorptive surface of the digestive tract are often unable to properly digest and absorb vitamin B-12 or other nutrients. Crohn's disease is an example of this. There are also certain medications that affect vitamin B-12 absorption, and deficiencies can also develop if the body is unable to produce a sufficient amount of the intrinsic factor. Finally, a B-12 problem can develop in the elderly when there is insufficient production of digestive stomach acid. This condition effectively decreases the amount of vitamin B-12 available for absorption, and affects an estimated 10 to 30 percent of the elderly.

One solution in such cases, especially if the absorptive surface is malfunctioning, is to give the B-12 via injection. That way, the vitamin goes directly into circulation, bypassing any need for the intrinsic factor, digestion or absorption.

As stated above, vitamin B-12 is essential for the creation of cells. The cells with the most rapid turnover, i.e., the shortest lifespan, are red blood cells. This explains why one of the first symptoms of a vitamin B-12 deficiency is a reduction in the number of red blood cells, otherwise known as anemia -- in this case, a "pernicious anemia." Red blood cells carry oxygen from the lungs to the working cells, then carry carbon dioxide from the working cells back to the lungs to be eliminated from the body. It makes sense, then, that certain types of anemia are associated with fatigue and weakness. It also makes sense that giving B-12 to a deficient body can help spark energy. If there is no vitamin B-12 deficiency to begin with, however, these shots would not be expected to do much.

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.