DEAR DR. BLONZ: Please help settle a dispute between my wife and me. We buy organic peanut butter, and the oil rises to the top. I would prefer to mix the oil in with the rest of the peanut butter whenever we get a new jar. But my wife wants us to pour out the oil, saying that we don’t need the excess fat. What are your thoughts about this? -- S.S., via email

DEAR S.S.: Peanut butter is a healthful food, with or without its top oil. The oil rises to the top due to gravity, along with the fact that no substances were added to the product to help emulsify it -- that is, to keep it all together. The amount of oil reflects the fineness of the grind, and the temperature and length of time the jar has been sitting.

Regarding the fat content: While a significant portion of the calories in peanuts come from fat, most of them stay with the solids. Assuming you will be eating the same serving size either way, the calorie savings will be minimal. A 2-tablespoon serving of peanut butter with all its oil will contain about 188 calories, 16 grams of fat, 8 grams of protein and 3 grams of sugars. If you were to pour off 3 tablespoons of oil (about 45 grams), then take a 2-tablespoon serving of this less-oily nut butter, you would have about 183 calories, 15 grams of fat, 9 grams of protein, and 3 grams of sugars. So the differences will be slightly fewer calories, a bit less fat, and a bit more protein.

Of course, nut butters also contain other nutrients, all of which are affected when the oil is removed, however slightly. Looking specifically at vitamin E, the 2-tablespoon serving of “un-poured” peanut butter will contain 2.9 mg of vitamin E (about 15 percent of the recommended daily value), while the same serving of poured peanut butter will contain about 2.5 milligrams (roughly 13 percent of the daily value).

DEAR DR. BLONZ: Thanks for your response to a recent letter regarding frozen salmon. What length of time is reasonable to freeze other meats -- beef, pork or chicken -- assuming they are kept and thawed safely, as you described in your response? -- B.N., Walnut Creek, California

DEAR B.N.: If properly wrapped and kept in an airtight container at 0 degrees F (-18 degrees C), meats will be as safe to eat when thawed as when they were initially frozen. The flavor and texture quality, however, will deteriorate with time. The major risk is freezer burn, which attacks the edges and surface of meat first.

You will have an average of about three months of safe storage for frozen meats, but this will vary according to the cut, whether it was cooked before being frozen, and the efficiency of your freezer. Be sure to place a date on the package.

Check out more detailed information on frozen-food safety by visiting fsis.usda.gov and searching for “frozen food.”

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 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’m 78, and for years I have been using canning salt for all my salt needs. My daughter now says it’s catching up with me. For the past three years, I’ve been suffering from weakness and a number of other problems. I hurt my back this year, and the discomfort has spread down to my hips. Is there a chance that the canning salt could be responsible? -- T.C., San Jose, California

DEAR T.C.: I encourage you to seek advice for the health issues you are now experiencing, but canning salt is not the villain your daughter believes it to be. It is no more harmful than regular salt. The difference is that canning salt does not contain sodium silico-aluminate, which is the anti-caking substance often added to table salt to keep it free-flowing. In addition, canning salt does not contain iodine.

One might ask why canning salt is on the market. The answer is that salt is often added to the water during the canning process, as it affects water’s boiling temperature and can reduce the time needed to safely can foods. However, the anti-caking agents in regular table salt were found to leave a powdery deposit on the jars. Canning salt arrived on the scene to solve this problem.

DEAR DR. BLONZ: What are your thoughts about ready-packaged lettuce, salads and cabbage slaws? Also, are there any concerns or benefits to eating baked potato peels? I wash and prick holes in the potatoes, then put them in a microwave-safe sandwich bag with a little water and cook them in the microwave. The resulting peel is soft and really good-tasting. -- V.G., West Orange, New Jersey

DEAR V.G.: Ready-packaged lettuces and slaw mixes undergo a thorough washing, are safe and, theoretically, ready to eat right out of the package. I do recommend, however, that all such packaged products be given a cold-water rinse to help crisp the greens before serving. Most national brands date-code their packages, so make sure you’re getting a fresh product. Aside from checking the date, look for browning or other discoloration as signs that the veggies are getting old.

The peel of the potato isn’t a nutritional powerhouse; the vitamins and minerals come primarily from the flesh. The peel does contain fiber and a small amount of iron, and provides a good contrast to the smooth texture of the flesh.

There’s absolutely nothing unsafe about eating potato peels, provided there is no greenish discoloration. I say this because potatoes can produce solanine, a bitter-tasting toxin that affects the nervous system. Solanine is produced when the potato is exposed to sunlight or allowed to sprout. It is most concentrated in the sprout, but it’s also present in potatoes having a greenish tint to the skin.

You can slow the production of solanine by storing your potatoes in a cool, dark place. Carefully cut away all sprouts and green portions before cooking, and be sure to discard any potatoes that taste bitter.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 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 attempts to lose weight continue to disappoint. I cut back significantly on food and calories and the numbers begin to decrease, but soon, the weight loss suddenly shuts down -- leveling off with no more drops. All this with no cheating! When I give up, the weight comes back and sometimes goes above my starting level. I continue to try, but am wondering if there is something I am not considering. -- F.S., Hayward, California

DEAR F.S.: Unfortunately, there is the risk that some of those who are repeatedly unsuccessful with drastic weight-loss regimens may end up disappointed -- and in some cases, in worse shape than if they hadn’t tried in the first place. Some get to the point that they no longer want to try.

Being slightly overweight is not necessarily a bad thing if you have a healthful diet and active lifestyle. But if weight is more of a serious issue, remaining obese means squaring off with increased risks of high blood pressure, heart disease, diabetes and other issues.

Getting back to your question: Could there be a bug in your approach, or is this more an issue with the body’s software? What gives the body this apparent cruel streak?

Consider that we make a conscious choice to go on these weight-loss diets, but the basic metabolic processes in our bodies are not in the loop on that decision. To these systems, the body has entered a state of famine, and it shifts to the assumption that a scarcity of food is the new status quo.

As soon as a restrictive diet is begun, the body’s innate drive for survival gets activated. Similar to the way we would have to cut back on spending if we lost our jobs and had to survive on assistance, the body automatically shifts into its version of economy mode. Depending on the severity of the calorie cut, actions would start with a slowing of body metabolism and a lowering of body temperature, along with other cuts that leave you feeling drained of energy.

We maintain our normal lifestyle through this period by conscious deception. We know that it’s coming, why it’s here and how long it will last. Consistent with the purpose of the diet, we want to make the body call on its energy reserves, which we are attempting to pare down. But as your reserves begin to drain, the body has this perverse desire to leave an IOU. Similar to how we might have “learned a lesson” and focused more on savings if we were fortunate to gain that job back, once we are “off” that diet, the body becomes more attentive to the handling and putting away of its energy. If frequent dieting is the norm in your life, this would especially be the case. The net effect can be a body with a greater focus on efficiency and holding on to its caloric stores.

One possible remedy is to refrain from focusing solely on drastic dieting. It is best to look beyond what we eat. Changes in lifestyle, such as regular physical activity, could provide the energy drain to swing the balance. We could be talking about nothing more than brisk walks.

Why not discard the idea of a “diet” entirely? After consulting your health professional, decide upon a reasonable ideal weight, and set this as your goal. Come up with a combination of food and activity that a person similar to you would require to maintain that weight; then on Day 1, begin eating and acting as if you were that person. Such an approach would mean a longer path to your goal, but the payoff is that you would never have to make any changes once there. It might be a way of turning the system around in your favor.

Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 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.