DEAR DR. BLONZ: The February 2014 Costco magazine had an article about brassica vegetables where it was said that boiled cauliflower is "devoid of nutrients." Isn't that a bit extreme? I love to eat it warm, and think the flavor is enhanced. I am not concerned about the vitamin C content from cooking, as I get that in many other foods, and I am sure the antioxidant chemicals are still present. I would like your opinion on this. -- T.B.

DEAR T.B.: I am pleased that pessimism prompted your note. That boiled cauliflower would be "devoid of nutrients" is nonsense, and it's unclear why such misinformation would appear. Heating does indeed reduce certain "heat labile" nutrients, and vitamin C is one that can be affected, but cauliflower has a great complement of healthful phytochemicals to offer.

Never forget that the nutrients in plant foods have become a part of their structure to assist in their growth, survival and reproduction. There is a broad variety of these beneficial substances in nature, and only by having a variety in our diet can we get the power of these substances on our team. Cooking, in many cases, helps enhance nutrient bioavailability. Check out the article in Scientific American that addresses this issue: tinyurl.com/nlvyyrk. Continue to enjoy your vegetables, fresh or properly cooked, and keep checking when you read something that sounds dubious.

DEAR DR. BLONZ: Please tell me about the benefits of sesame oil. Is it OK to use in salads and also to saute vegetables, chicken, meat and fish? Are there any reasons why I should not use it? I currently use extra-virgin olive oil and balsamic vinegar for my salads. -- J.P.

DEAR J.P.: Sesame oil is a healthful oil that is composed of approximately 40 percent monounsaturated fatty acids, 42 percent polyunsaturated and 14 percent saturated. It is source of tocopherols (such as vitamin E) and lignans, both of which act as protectants for the sesame seed. Pure sesame oil has a mild flavor and a high smoke point, making it ideal for high-heat cooking methods including those you mention. Toasted sesame oil, pressed from the toasted seeds, has a distinctive nutty flavor used to complement many dishes in Asian and other cuisines.

DEAR DR. BLONZ: When playing sports, we freeze half a bottle of water, then add water to it to keep it cold. We then refill the bottle as we drink it until the ice melts. I have read that this is a safe practice, and yet people tell me the plastic breaks down and can cause cancer. I use pre-bottled water from the store. -- D.O., Walnut Creek, Calif.

DEAR D.O.: The water bottles you buy at the store have been specifically designed for water. As long as the bottle is completely cleaned and allowed to dry between uses, there is no evidence that any problem exists. There is a bogus cancer-scare email going around with misinformation on this topic; go to tinyurl.com/cgq874 to sort fact from fiction.

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: With the reports about food poisonings from fruits and vegetables, I wanted to know the best way to clean produce. Is water enough, or should I use something additional, such as a diluted solution of dishwashing liquid (not enough to affect the taste)? -- J.D., Charlotte, N.C.

DEAR J.D.: Fruits and vegetables are not waterproof; unless they have been waxed, they can, to varying degrees, absorb liquids or the components they contain. This means that any fluid you use to wash your vegetables should be approved for food use. Dishwashing detergents, in general, are not. It is important to always clean your produce in potable, running water before eating. This will usually suffice, but if you desire a product that does more, you should seek out one that is specifically designed for washing produce.

DEAR DR. BLONZ: Is there anything to the theory that the healthiest foods are the ones that grow in the area where you live? -- M.S., San Diego

DEAR M.S.: Indigenous foods might be more familiar to our taste buds and to our digestive tracts, but in general, there is no evidence that they possess any special health attributes.

DEAR DR. BLONZ: Is there any unique nutritional value to the Mexican plantano? What is the number of calories in a large, 6-ounce plantano? -- S.Q., Poway, Calif.

DEAR S.Q.: A 6-ounce Mexican plantano, also known as a plantain, contains about 218 calories, along with 2.3 grams of protein, 57 grams of carbohydrate and less than a gram of fat. It is a vegetable, but it looks like large, greenish banana with a mottled, rough peel. Plantains blacken when fully ripe, but can be broiled or sauteed at any degree of ripeness. They are a good source of dietary fiber and vitamin C, along with folate, carotene and potassium.

DEAR DR. BLONZ: What exactly is "palmitate," and why is it in powdered milk? -- N.T. Oakland, Calif.

DEAR N.T.: When you see "palmitate" in the name of a substance, it indicates a compound that is made with palmitic acid, a saturated fatty acid. The name comes from the fact that it is a principle fat found in palm oil. In milk, the vitamin A, or retinol, is combined with palmitic acid; the resulting compound is called either vitamin A palmitate or retinol palmitate. You might also see palmitate in other compounds, such as ascorbyl palmitate, which is a combination of palmitic acid with vitamin C (ascorbic acid).

Interestingly enough, palmitate makes up about 25 percent of the fats found in mother's milk. It's also present in human lung surfactant, a substance that coats the inside of our lung surfaces and allows us to breathe.

The amount of palmitate in powdered milk is negligible. It is only there as an "escort" for the small amount of vitamin A added to the product.

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: I was ill recently and I believe it was due to the great amount of stress I was under at work. A friend recommended Rescue Remedy for stress and lack of sleep, but I don't really like taking homeopathic stuff. Have you heard of it? Also, I have been reading the monthly Nutrition Action magazine put out by the Center for Science in the Public Interest (CSPI) for over 20 years, and always feel like I get something out of it, just as I do with your column. My son, who is a molecular biologist, kind of pooh-poohs magazines like this. What do you think? -- T.N.

DEAR T.N.: I am not a supporter of homeopathy. Check out tinyurl.com/mosf6o5 for a recent column on this topic. As for Rescue Remedy, it is my understanding that this product is based on substances referred to as Bach flower remedies. A report in the August 2010 Swiss Medical Weekly presented a systematic review of randomized clinical trials using Bach flower remedies and it concluded there was no difference between the use of the remedies and placebos. As a result there is no basis for me to endorse this product. As for its potential for harm, there is no evidence that it would be harmful, except, perhaps, to one's pocketbook and the delay in addressing the true source of the problem(s).

Regarding CSPI, I have been a member/subscriber to Nutrition Action since they began and consider CSPI to be an important voice. They have an excellent crew of researchers, writers and legal experts and their work represents a positive force. You might also check out the Berkeley Wellness Letter. I am a member of their editorial board and find their evidence-based approach to provide excellent guidance.

DEAR DR. BLONZ: Does beer have a greater diuretic effect than other types of alcohol? When out with friends, I tend to have a couple, but then find myself up multiple times during the night. Would it help to eat salty foods while drinking? -- S.G.

DEAR S.G.: Alcohol affects how much urine the kidneys produce and send into the bladder for elimination. Interestingly enough, it is the amount of alcohol, more so than the amount of fluid, that determines this effect. This means that a shot of liquor, a bottle of beer or a glass of wine can translate to the same diuretic effect.

Your mention of salty foods adds an additional wrinkle. Taking in sodium chloride (salt) tends to increase thirst, since the body is engineered to eliminate excess sodium, but it first has to dilute the sodium to a tolerable concentration. This explains why we cannot satisfy thirst by drinking seawater: It contains a salt concentration above that desired by the body, so any consumption of seawater to satisfy thirst sets the body back even further. You can see where things might head if you then seek to satisfy a salt-bred thirst by consuming alcoholic beverages. Even if you drank plain water, your body would still need to produce urine to get rid of its excess sodium.

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.