On Nutrition

DEAR DR. BLONZ: Could you tell me if roasted or raw would make any difference with nuts, health-wise? What about the difference between oil roasting and dry roasting? One proponent of raw peanuts states that one half-cup of raw peanuts has 430 calories, but processed into peanut butter, a half-cup contains 780 calories. How can this be? -- S.S., Malibu, Calif.

DEAR S.S.: You are mixing volume with weight. There is space between those peanuts in the half-cup, which weighs about 73 grams. Contrast this with a half-cup of peanut butter, which weights 129 grams. If you were to look at similar weights of these two foods, the caloric content would be comparable.

When you roast nuts, or any food for that matter, it can bring about flavor-enhancing chemical reactions. With nuts, this can be accomplished with or without oil. Dry roasting requires specially designed ovens and utilizes hot air. Salt, paprika or other flavorings can then be added if desired.

Although dry-roasted nuts contain no added oils, there will only be a nominal difference in overall fat content as compared to oil-roasted nuts. This is because half the weight of the nut, and over 70 percent of its calories, come from its fat content. A honey-roasted nut will contain less fat per serving because some of the weight is taken up by the sugary coating. In terms of nutritional value, the high heat process will destroy some of the folate and thiamin (vitamin B1), but the other nutrients are unharmed.

Raw peanuts will have a different taste from roasted ones, but a comparable fat content. One item of interest is a study in the October 2000 issue of the Journal of Allergy and Clinical Immunology, which reported that raw peanuts provoked less of an allergic response in sensitive individuals than roasted peanuts. However, as there raw peanuts carry a slightly higher risk of microbiological contamination, they are not recommended for individuals with compromised immune systems. Raw peanuts should be stored in the refrigerator. Only buy them from sources that sell a lot of them, and avoid places where the raw peanuts might have been sitting around for a long time in a bulk bin.

DEAR DR. BLONZ: Can you explain why the vitamins and minerals in a dietary supplement expire? What is the best way to store these products? -- S.H., Arlington Heights, Ill.

DEAR S.H.: Vitamins are reactive compounds that play an integral role in the chemical reactions that comprise our metabolism. Although mineral supplements tend to be quite stable, vitamins can slowly lose their potency over time. The factors that encourage breakdown are humidity, temperature and light. Formulas that contain fat-soluble nutrients tend to break down the fastest. The best way to store products is in a tightly sealed container in a cool, dark place. Many supplements include moisture-absorbing capsules or packets to help maintain product quality. Product expiration dates indicate when the vitamins can be assured of full potency -- assuming that the product has been appropriately stored.

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: You have written before about the nutrients in nuts and their value as a snack. For the last several months, I have been researching the fat content in peanuts still in the shell. From everything I have read, peanuts contain lots of monounsaturated fat, but there is no mention of saturated fat. But when I check packaged unshelled peanuts, the Nutrition Facts labels reveal a different story. The packages list 2 grams of saturated fat per serving, which is about half a cup (with shells). There is no mention of monounsaturated fat. This difference is important, since saturated fat can form cholesterol. Could you shed some light on this mystery? -- J.B., New Orleans

DEAR J.B.: Peanuts are predominantly monounsaturated fat (48 percent), but there are a bunch of polyunsaturated fatty acids (33 percent) and some saturated fats (19 percent) as well. This is usually how it is: Foods often contain a mixture of all the different types of fat, but tend to have more of one type than the others. The food then becomes known as a source of that type of fat. There is a chart providing the breakdown of typical food fats at tinyurl.com/cbwrox.

I would not be concerned with the little saturated fat found in peanuts. Saturated fat does not turn into cholesterol, and small amounts of it should not be an issue. It can contribute to problems when it becomes the predominant fat in your diet, AND when the rest of your diet is missing the variety of healthful foods that empower your body to handle the fats you eat. The reason that monounsaturated fats are not always present on food labels is that there is no requirement to list them. The only items mandated are total fat and saturated fat. Stay well.

DEAR DR. BLONZ: I wanted your take on xanthan gum and guar gum. They may not be harmful or toxic, but they do cause constipation in me, which has been proven time and time again. Since their purpose seems to be to bind things together, this would make sense. I avoid them like the plague. -- I.J., via email

DEAR I.J.: Not much of a plague here. Although they are called gums, they do not really "gum up" the digestive system. These additives are used in relatively small amounts, as evidenced by the fact that they are toward the end of many food ingredient lists. They can act as thickeners, texturizers, emulsifiers and/or stabilizers. Xanthan gum, for example, is often found in salad dressings and sauces for these purposes. It is also finding more uses these days in gluten-free foods.

There is no evidence, or reason to believe, that the small amounts of xanthan or guar gum would contribute to constipation. At levels higher than their normal usages, they might actually do the opposite, because they would add more bulk to the foods traveling through the digestive tract. That being said, we are all individuals; regardless of what might be a typical response, if you are convinced that these substances cause problems for your body, then by all means avoid them. There is certainly nothing essential that you would be missing.

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: My husband and I have just made the move to quit smoking. We are now trying to flush our systems of any toxic materials, so we are drinking a lot of water and have been eating very lightly. Is a weeklong liquid diet a good idea to help take the load off the body so that it can concentrate on healing? We are also trying to rest a great deal. Any other suggestions on how to get through this in the best way? -- T.S., Charlotte, N.C.

DEAR T.S.: Your body will soon gain the upper hand. Water is a great conduit for elimination, so you are on target there, but so is healthful food. Many people have an urge to eat more after they quit, so you should have some foods around of low caloric density. Eat normally at mealtime, but be alert to the quality of your snacking. Good between-meal foods would include fresh fruits, cut vegetables, pretzels (whole wheat if palatable), and even sugar-free gums and candy. Other suggestions might include rice cakes, air-popped popcorn, whole-grain dry cereals, raisins and other dried fruits, and even some nuts and seeds. Small meals, eaten slowly, can help fill you up without contributing an excess of calories.

You note that you are resting, but if you have the OK from your doctor, it may help to begin going on walks, riding bikes, dancing or any other activity the two of you might enjoy. Not only will this help control any potential weight gain, it will be an important first step in telling your lungs and muscles to get in step with your new plane of existence. It also can provide some of the same pleasant substances, known as endorphins, that the body produced in response to smoking. They often play a role in the cravings that make it difficult to stop smoking, but studies have shown that you can get a similar kick from exercise. How's that for a great turn toward health! Please do check with your physician first, in case there are other issues that need to be considered.

Don't give up if you gain a few pounds. Those can be lost later. The key is to get over the proverbial "hump" of four weeks or so, after which the worst of the withdrawal symptoms will be history. There are many programs and support groups around that can be of help. Finally, you definitely need to spend some time giving yourselves a pat on the back. I congratulate you both.

DEAR DR. BLONZ, I learned in school that riboflavin in milk is destroyed by light. If that is true, why is milk often sold in clear containers? Am I wasting my money by paying more for it in opaque containers? -- N.F., Puma, Ariz.

DEAR N.F.: Milk is a perishable food, and exposure to natural light or bright flourescent light can destroy a percentage of the riboflavin (vitamin B2), vitamin C and vitamin B6, and also encourage the development of "off" flavors. Light intensity and the duration of exposure determines how much of these nutrients will be destroyed.

Appropriate temperature control is an important factor in nutrient preservation, but proper containers can also offer protection. Storage in an opaque container, such as a paper carton, seems to be best in this regard, with clear glass at the other end of the spectrum.

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.