DEAR DR. BLONZ: A local store was selling butter in the dairy section, but it was not refrigerated. Then, while at a friend’s house, I saw that she kept her butter at room temperature year-round. Her thought was that butter is saturated fat, so there was nothing that could go wrong, plus it makes the butter easy to spread. She does not feel there is any danger in this practice. I know it is wrong and unhealthy, but I cannot articulate to her the reason why. I would also like to pass something on to my local store. -- K.E., Hayward, California

DEAR K.E.: Storing butter at room temperature, exposed to air, will invite spoilage. The issue is that fats can react with oxygen in the air. As this happens, the fats become rancid; they develop “off” flavors and are no longer healthy to eat. It is a gradual process, and the reaction is slowed considerably at refrigerator temperatures.

It is true that saturated fatty acids tend to be more resistant to this type of breakdown, but they are not immune. Even saturated fats can oxidize and turn rancid. It is also important to consider that while most people think of butter as entirely “saturated,” this is not the case. According to the USDA, butter fats are 68 percent saturated, 28 percent monounsaturated and 4 percent polyunsaturated.

As a fat becomes rancid, it develops a foul, unappealing taste. However, there are degrees of rancidity, and one cannot always identify low levels, especially when present in dishes with strong flavors. Another insidious fact is that eating food with oxidized fats will not bring on food poisoning-like symptoms. Rather, the effects are cumulative, and thought to play a role in the risks of cardiovascular disease, cancer and aging.

You help prevent spoilage by keeping fats in well-sealed containers that prevent exposure to air, and by storing them in an appropriate low-temperature environment.

There is also a chance that butter might be affected by yeast and mold organisms in the air. Ongoing storage at room temperature would make butter vulnerable to this type of attack, as well.

My final spread: You won’t have to toss the butter if you accidentally leave it out overnight, and it is reasonable to take it out before mealtime if you want a softer spread. But the habitual storing of butter at room temperature is not recommended. If kept in an airtight container, such as a crock or butter keeper, the butter can be kept out for a few days, but even this method is not recommended with indoor temperatures that rise about 70 degrees F.

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 have heard stories from a friend about what a microwave does to food: that it changes the food’s composition, or that your body doesn’t recognize food in the same way after it has been microwaved -- that microwaves change food “at the molecular level.” I thought they caused molecular “friction,” which caused heat. That’s what I learned in my X-ray and radium physics course in college. My friend will no longer heat food in a microwave. Should I be concerned? -- A.G., Phoenix

DEAR A.G.: Searching for “microwave dangers” on the internet will reveal many sources of blatant misinformation, some of which border on the entertaining with their conspiratorial bent. As you correctly noted, microwaves heat food by causing molecular movement and heat-producing friction between the molecules. When you turn off the microwave, that stimulation ends. Except for generating more heat energy, there is no “change at the molecular level.”

One risk would be from overheating an item, but this can happen with any form of cooking. Your college course was correct; your friend is not. Food appropriately heated in a microwave remains food, and will be “recognized” by all bodily systems: appropriately digested to allow absorption and utilization of its nutritive value. We should all get in the habit of challenging nonsense before we swallow it.

DEAR DR. BLONZ: I am looking for information on automatic hot-water dispensers. We received one of these as a gift, and it will get lots of daily use in our home, seeing as we are all tea drinkers. But we have heard that using this machine over the long run could have adverse effects on our health, due to the heating element coming in direct contact with the water. We were even told that it could cause cancer with constant use. I’m hoping that this is only an “old wives’ tale.” -- S.T., Oklahoma City, Oklahoma

DEAR S.T.: I encourage you to enjoy your gift with the knowledge that there is no scientific basis for the concerns you mention. There is no logic, nor is there any objective documentation of “adverse effects” from a normally functioning heating element in a hot-water dispenser. Be sure to read the manufacturer’s directions for use and maintenance; periodic cleaning to prevent the buildup of mineral salts will be key.

DEAR DR. BLONZ: I have just been turned on to baking vegetables wrapped in parchment paper. They are incomparable in flavor. I wonder why parchment paper rarely shows up in recipes. Is it safe to eat food cooked in this nonstick paper? -- H.W., Hayward, California

DEAR H.W.: Parchment paper is made from cotton fiber and wood pulp. The paper is odorless and flavorless, and can be used as a pan liner or to wrap foods for cooking. Parchment paper provides a moist-heat method to cook foods “en papillote,” which is French for “cooked and served in paper.” It’s unclear to me, also, why this technique doesn’t get more use.

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: A recent visit with my doctor revealed that my thyroid is low, and she recommends I begin taking a synthetic thyroid hormone. I’m considering it, but I confess that I prefer natural methods, because my body doesn’t always respond well to medication. Can you suggest ways, other than a synthetic supplement, to raise my thyroid level? Would it be wise to take an iodine supplement? -- S.T., Tulsa, Oklahoma

DEAR S.T.: Thyroid hormones regulate the metabolism in the cells of the body. To release its hormones, the thyroid gland, which sits just below the larynx (voice box) in the throat, requires the mineral iodine and the stimulating presence of another hormone: the appropriately named thyroid-stimulating hormone (TSH). Hypothyroidism is the condition of insufficient thyroid hormone. This can be due to problems with the gland itself, or due to an insufficient amount of TSH. There are a number of medical conditions that can play a role in hypothyroidism, so your doctor should fill in the details of what’s going on in your particular case. (Read more about this at tinyurl.com/yd26athu.)

You mention iodine; a deficiency of this essential mineral can indeed hamper the ability of the thyroid gland to produce its hormone. In such cases, the thyroid gland often enlarges, and the condition referred to as a “goiter” results, with a characteristic swelling about the front of the neck. Most people, however, get more dietary iodine than they need, so it is unlikely that an iodine deficiency is the problem.

It wasn’t always that way. Iodine is plentiful in the ocean, but there was a time when it was not well-distributed inland. Foods containing iodine used to be limited to seafood, crops grown in coastal areas, and dairy or meat products from animals that had grazed on iodine-rich feed. During that period, iodine-deficiency goiters used to be more common. With the advent of iodized salt, perhaps our first “functional food,” this condition virtually disappeared. The typical iodine intake is now well above required levels.

Be aware that if you are not iodine deficient, taking additional iodine will not cause your thyroid to produce more, and excessive intakes can be harmful.

There are compounds called goitrogens that can interfere with the use of iodine by the thyroid gland. These compounds are found in foods such as cabbage, Brussels sprouts, kale, cauliflower, broccoli, kohlrabi and turnips. Goitrogens, however, tend to be inactivated by cooking, so unless you are eating lots of these vegetables raw, and on a daily basis, it’s doubtful that they would be involved.

Whatever the cause, if you have hypothyroidism, it is important that your condition is treated. The symptoms of inadequate production of thyroid hormone include sluggishness, intolerance of cold temperatures, depression, poor muscle tone, and weight gain. There is also an increased risk for heart disease. The use of Synthroid (a synthetic thyroid hormone) may be a reasonable option, but make sure you discuss all your concerns with your physician.

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.