DEAR DR. BLONZ: Are there any health benefits from eating raw almonds, as opposed to roasted ones? Does oil roasting them add many calories from fat, compared to dry roasting? Also, is it best to store raw nuts in the refrigerator? -- T.N.P., via email

DEAR T.N.P.: Roasting nuts, or any food, for that matter, helps to bring about flavor-enhancing chemical reactions. This can be accomplished with or without the use of oil.

Dry roasting utilizes only hot air, and is done in specially designed ovens. Salt, paprika or other flavorings can then be added. Although dry-roasted nuts do not contain additional oils from the roasting process, this does not amount to a large difference in overall fat content. Half the weight of the raw nut -- and over 70 percent of its calories -- come from its oils. Honey-roasted nuts will contain less fat per serving, but only because some of their weight comes from the added sugars.

In terms of nutritional value, any high-heat process will destroy some thiamin (vitamin B1), but the other nutrients are relatively unharmed.

Nuts tend to be packaged in airtight bags or containers. They should be stored that way and kept in a cool, dry place to prevent mold and the slow oxidation of the oils. Refrigeration in a sealed container for raw nuts, or any nuts, makes sense as it effectively slows these damaging processes to an even greater degree. This is less of an issue if the nuts will be gone within a month after opening. But look to refrigeration if you want to store these perishable foods for longer periods of time.

DEAR DR. BLONZ: I appreciated your recent article concerning oils, but the term "room temperature" is vague. Please advise me of what you consider the temperature range for "room temperature." The reason for my request: My elderly parents keep their house between 85 and 95 degrees F, day and night, during our dry, hot, 100-degree California valley summers to save on electricity. Believe me, this is not what I consider a comfortable room temperature. My pleas to keep whole wheat flour and other whole grains, seeds and oils in the fridge during the long summer months fall on deaf ears, as they point out they have clearly been storing them at "room temperature." -- K.F., via email

DEAR K.F.: In the U.S., the temperature cited as "room temperature" is usually 68 degrees F, and the range commonly used is 68 to 72 degrees F. It is not a precise measure, and I have seen the range expressed in Centigrade as 20 to 25 degrees C (68 to 77 degrees F).

If one were in the tropics or in a desert climate in the U.S., room temperate would, of course, be higher. The guidelines for food storage in hot climates is different, as exposure at "room temperature" there would hasten spoilage. If there is no stated recommendation to refrigerate the product in question, it makes sense to at least store perishables in a cool place in the house. If there is no such place, perishables should be kept in the fridge. If this is not practical, my advice is to buy perishables in smaller containers. Please pass this on to your parents.

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: Processed foods, even some that brag about their "all natural" ingredients, often choose to add food coloring. Where do natural and artificial food colorings come from? What does "FD&C" stand for when used to describe a color on the label? How concerned should I be over the safety of food coloring? -- B.B., Los Angeles

DEAR B.B.: The use of food colors is controversial because their purpose is to change the appearance of a food into one that is more acceptable to the consumer. It's nothing new, as archaeologists have identified the use of cosmetic colors dating back as far as 5,000 B.C. Research has shown that if the colors of a food look wrong, people have difficulty detecting specific tastes. One classic study, for example, demonstrated that some volunteers couldn't correctly identify strawberry flavoring when it was tinted green. And in a classic 1970s experiment, volunteers were fed a meal of steaks, peas and french fries under lighting conditions that masked their appearance. A number of volunteers became ill when the lights were raised at the end of the meal to reveal a blue steak, red peas, and green French fries.

One rationale for the use of colors in processed foods is that natural color compounds tend to be destroyed during processing. When used as additives, however, natural colors are rarely "natural" to the food in which they're used. Rather, they are color-rich chemicals that come from animal, vegetable or mineral sources, and this is what allows them to be called "natural." Artificial colors, by contrast, tend to be made from petroleum-based substances.

The components of natural red food coloring, for example, can be extracted from beets, but it also can come from carmine, a crimson pigment from the shell of a Central American insect. Both are considered "natural" red colors, and they're used in everything from fruit drinks to candy to strawberry ice cream.

If a color comes from a natural source, it is exempt from certification. By contrast, every batch of an artificial color must be certified safe by the Food and Drug Administration before it can be used. The FD&C in the name of an artificial color stands for the Food, Drug and Cosmetic Act, the 1938 legislation that gave the government the authority to regulate the dyes used in foods, drugs and cosmetics. The artificial colors used in foods are identified by number and appear on the ingredient statement as, for example, "FD&C Blue #2." A complete list of FD&C colors can be found at tinyurl.com/oenz94w.

The safety issue is complicated. In general, food colors have a good safety record, but over the years a few "numbers" have been taken off the market when they were found to cause cancer in animal experiments. Keep in mind that unrealistically large amounts of the chemical are often used to provoke cancer in these experiments, while only minuscule amounts of colors are ever used in foods. Other issues include an ongoing debate about an association between artificial colors and hyperactivity in children.

The big picture here is that color additives don't provide any health value to a food, the main mission being to make a processed food appear more natural or wholesome. There is no real basis to recommend them. The fact that you don't find food color additives in whole foods, such as fruits, vegetables and grains, speaks volumes.

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 am interested in your thoughts on linoleic acid. I've been collecting linoleic acid research these past few years, and what I've learned thus far paints a grim picture. I believe we should be cutting this fat out of our diets. I found that reducing my soybean oil intake (which I did in 1994) and peanut butter intake (in 2009) has done my body a world of good. -- D.B., via email

DEAR D.B.: Linoleic acid is an essential fatty acid. This means that it is needed for normal health, but the human body cannot make sufficient amounts on its own. As a result, linoleic acid needs to be provided in the diet.

But how much? Just because something is essential does not mean it should be consumed to excess. For example, there is reasonable evidence that a strict vegetarian (or even vegan) diet contributes to health, but that does not mean that we should overdo it with meat-free junk like candy, beer and potato chips. Balance and whole foods are the key, and this is also the case with the fats we consume.

Linoleic acid is the primary polyunsaturated fatty acid in nuts and seeds. Vegetable oils made from these will be high in this fatty acid. Unless there is specific negative evidence -- such as what was learned about the need to avoid industrially produced trans fats -- we do ourselves a disservice when we become overly fixated on individual food components.

That said, you don't want to overdo it with any fat, whether it is lard, coconut oil, fish oil, vegetable oil or even olive oil. The mix of healthful whole foods is what works. Think of them as a system perfected over time by nature.

Fats are the most concentrated form of caloric energy in nature; plants use fats as an energy source to nourish their seeds during the critical development period before the plant can begin to make energy on its own. That makes fats, and the maintenance of their wholesomeness, a vital project for a successful plant. The plants that have succeeded have evolved to produce their own set of "essential" protectants. These phytochemicals keep the elements, such as the oxidizing rays of the sun, or the invasion of insects or bacteria, from destroying their energy supply or doing other types of damage that can threaten their survival and propagation.

When you eat a whole food, you get the entire package, including these protectants. When you eat a variety of whole foods, you get a variety of protectants. Contrast this with fabricated foods that are formulated to achieve a particular taste, texture, appearance, functionality and shelf life -- not to survive or reproduce. Be less concerned about linoleic acid and more focused on making it just one of many fats in your healthful diet. Toss in an active lifestyle with limited stress, and you would definitely have something. Check out my online book that goes aisle-by-aisle through the supermarket for more information about food choices. It is available free of charge at blonz.com/guide.

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.