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.

DEAR DR. BLONZ: On National Public Radio, a University of Minnesota nutritionist claimed that whole-wheat flour today is so highly processed that it is absorbed by the digestive system just as quickly as white flour, and impacts blood sugar levels in the same way. The nutritionist recommended whole-wheat bread made from stone-ground wheat berries instead. How valid is the claim about processing? Does whole-wheat bread still have other nutrients that white bread lacks? Would whole-wheat bread made from sprouted wheat be a good alternative? -- D.W.M., via email

DEAR D.W.M.: Your mention of a University of Minnesota nutritionist speaking about whole grains suggests Dr. Joanne Slavin. She is definitely an expert in the field of whole grains, but I couldn't imagine her making such statements, so I had to check it out. I found the NPR program transcript online at tinyurl.com/cj6vstq. It seems you are misattributing statements by the other guest, Dr. David Ludwig, an esteemed pediatrician who studies obesity.

While there are different types of wheat being grown nowadays, in general, the whole-wheat flour of today is not much different than the whole-wheat flour of earlier times. The healthfulness of whole grains has led to a greater presence of whole-wheat flour in some processed foods, but that should not serve to denigrate the value of this important class of nutrient substances. A whole-grain bread will have nutrients, fiber and phytochemicals not found in white bread. This being said, however, some vitamins and minerals are often added to enriched white bread. I recommend that at least half our grains should be whole grains.

It is never a good idea to eat a bunch of carbohydrates on an empty stomach, whether it is sugar-sweetened soda, white bread, or even whole-wheat bread. It's best to eat in such a way that the glucose in carbohydrates has the smallest impact on blood sugar levels; eating sweets and carbohydrates on an empty stomach does the opposite. (About the only exception might be a piece of fruit, because fructose, or fruit sugar, is absorbed more slowly.) Having carbohydrates as part of a mixed meal that includes protein and fat will slow the release of the food from the stomach and accomplish the goal of minimizing the impact on blood sugar. All the better if you eat slowly.

I encourage you to re-read that NPR piece on whole grains. I support what Slavin said; it is definitely a more positive and practical approach. You also asked about sprouted whole wheat. This does represent an alternative, but choose it only if you enjoy the flavor and texture, not because it is significantly superior. Always check the Nutrition Facts labels on products you buy, as well as the list of ingredients. Having a whole grain in the first position is a definite asset, and if the package displays a whole grain stamp (wholegrainscouncil.org), as mentioned on the radio show, all the better. All of this provides good guidance.

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.