Saturated fat science is evolving

119577643In a recent column, you said oils that are high in saturated fat aren’t heart-healthy. But I’ve read about the benefits of tropical oils, especially coconut oil. What’s up?

The standard guidance to limit intake of saturated fats, including those from tropical oils, to 10 percent of total calories hasn’t changed. That message is nearly universally recognized as sound advice.

But research on diet and health is ongoing. What you’re witnessing is the scientific method in action. That is, scientists conduct studies and publish data and analyses; other scientists review those findings and either build on them or dispute them.

Eventually, consensus builds and standard guidance develops — which is then questioned, tested, adapted, supported or refuted, and on and on.

For example, for decades, evidence has accumulated to show that saturated fat increases blood cholesterol, thus raising the risk of heart disease. But in 2010, an analysis of 21 studies was published in the American Journal of Clinical Nutrition; it concluded that the link between saturated fats and heart disease is questionable. But in the same issue, the journal published an editorial questioning the findings, and a later issue included a letter from other researchers questioning the authors’ methods.

One of the confounders in this debate is that not all saturated fats are created equal. Different kinds have different types of fatty acids: lauric, palmitic and stearic, for example, and they have different effects. For instance, about half of the saturated fat in virgin coconut oil (the type that’s not hydrogenated) is lauric acid, which raises HDL cholesterol — the “good” cholesterol — even while raising LDL cholesterol — the “bad” type. Also, since they are plant-based foods, coconut and other tropical oils also contain antioxidants, which have their own positive health effects.

But be skeptical about some of the claims being made — that coconut oil combats everything from HIV and Alzheimer’s disease to acne and weight gain. While you might hear compelling anecdotal evidence and even read some preliminary studies, so far there’s insufficient data to warrant changes in consumer guidance on intake of coconut oil or other saturated fats.

At the same time, evidence is mounting that if people reduce saturated fat but instead eat more refined carbohydrates, they’re actually worse off in terms of heart health. But it appears that replacing saturated fats with unsaturated fats remains beneficial.

The scientific process can lead to confusion, or even mistrust of the scientific community. But over time, it has proven its worth.

Watch sugar intake over holidays

159190816I have a sweet tooth. I’ve been cutting back on sugar lately, but I’m worried about the holidays and all the extra sweets. Do you have any guidance?

It’s a good idea to eat less sugar — added sugar, that is. It’s estimated that Americans consume 16 percent of total calories from added sugar — the kind of sugar that’s added to foods during processing or preparation, as opposed to the type naturally found in fruit and other whole foods.

That 16 percent is equal to 320 calories a day on a 2,000 calorie-a-day diet — far more than recommended. The American Heart Association suggests that women consume no more than 100 calories a day from added sugars, and men no more than 150 calories a day.

The nutrition community agrees that cutting back on sugar would be a very good thing. Some experts, including the authors of a commentary published in the journal Nature in February 2012, even go so far as to call added sugars “toxic” and advocate regulating them like alcohol. Others are more moderate, saying that added sugars are just a source of needless empty calories and cutting back would help people with their weight and triglyceride levels, which increase when you eat too much sugar.

In either case, you should know that overdoing it on added sugars — or other carbohydrates, including white rice, bread and other refined grains, could cause your blood sugar to spike and then drop, possibly suddenly — and that variation in blood sugar could trigger more sugar cravings.

Be aware that avoiding added sugars can be a challenge. They’re not only in cake, cookies, pie, candy and ice cream, but they’re also in many processed foods, including barbecue sauce, salad dressing, canned soup, pasta sauce, granola bars, breakfast cereal, instant oatmeal, flavored yogurt, frozen dinners and many other foods. The largest contributor of added sugars in the diet is high-calorie soft drinks.

Looking at the “sugar” line on the Nutrition Facts label doesn’t always help, because it lumps naturally occurring sugar together with added sugars. So you need to look at the ingredients listing to determine if the product has added sugar. Look for words like cane crystals, corn sweetener, evaporated cane juice or syrup, fructose, dextrose, glucose, sucrose, fruit juice concentrates, agave nectar (or other types of nectar), high-fructose corn syrup, honey, malt syrup, or molasses.

Or more simply: Eat fewer processed foods and more fresh produce; use fresh ingredients when cooking; and drink more water and milk. And limit yourself to just one or two of those Christmas cookies at a time.

Focus on safety with mailed food gifts

Last year we received a gift in the mail and didn’t open it until Christmas Eve. The box contained cheese spreads that said “Keep refrigerated” on the label. They had been at room temperature for more than a week, so we threw them out. But since then, I’ve seen some types of cheese spreads sold at the grocery store on the shelf. Were we being overly cautious?

If the label said “Keep refrigerated,” you absolutely did the right thing. But it’s no wonder you’re confused. There are many different types of cheese and processed cheese products, and some don’t need to be refrigerated until they’re opened. It depends on several factors, including the product’s moisture content, its level of acidity, its packaging, and how it was made and processed. But a “Keep refrigerated” instruction on the label is a sure clue that the product should not be kept at room temperature for extended periods.

The U.S. Department of Agriculture’s Food Safety and Inspection Service offers a detailed fact sheet to help you sort out how to keep perishable foods safe when delivered over long distances. For the lowdown, go to http://www.fsis.usda.gov and search for “Mail Order Food Safety.” It includes a chart with time limits for storage of a wide variety of foods at room temperature and in the refrigerator or freezer. Among the food safety tips it recommends are:

  • When a food labeled “Keep refrigerated” arrives, open it immediately and check its temperature with a food thermometer to make sure it’s 40 degrees F or lower. If it’s warmer than that, throw the food away and contact the company.
  • If you’re ordering perishable food to be delivered to someone, let them know when it will arrive. Perishable foods can be sent safely if packaged and handled properly before, during and after delivery.
  • If you’re sending perishable food from home, pack it in a reusable insulated cooler with enough dry ice or frozen gel packs to keep the food cold. Mark “Keep refrigerated” clearly on the outside of the box, as well as “Contains dry ice” if that’s what you’re using to warn the recipient. (Dry ice should not be touched with bare hands.) Use next-day delivery whenever possible.

Plenty of options to replace olive oil

What kind of oil is the best to use for heart health? I tend to use olive oil all the time, but I’ve been looking for alternatives.

Many consumers wonder about olive oil these days, ever since a 2007 article in The New Yorkerrevealed that much olive oil sold worldwide as “extra virgin” doesn’t meet that designation’s premium-grade standard, having been mixed with other types of oil. The report was corroborated in 2010 when the University of California-Davis reported that 69 percent of imported olive oil it tested didn’t meet the standard.

Although questions about quality and truth-in-labeling remain (for details, seehttp://www.truthinoliveoil.com/), olive oil remains a heart-healthy option. Most types of oil normally used for cooking are high in unsaturated fats, the type considered to be heart-healthy when used in moderation and when used instead of saturated or trans fats.

There are two types of unsaturated fats — monounsaturated and polyunsaturated. The American Heart Association doesn’t advocate one type over the other. Both can help reduce blood cholesterol levels, which helps reduce the risk of heart disease.

Oils highest in unsaturated fats (in order) are safflower, canola, flaxseed, sunflower, corn, olive, sesame and soybean oil. Peanut oil and cottonseed oil actually contain a bit more saturated fat than what you’d find in regular margarine.

On the other hand, both coconut oil and palm kernel oil have very little unsaturated fat. In fact, they have more saturated fat per tablespoon than butter, and palm oil isn’t far behind. If you’re looking for heart-healthy oils, avoid the tropical types.

Monounsaturated fats tend to be good sources of vitamin E, which most Americans don’t get enough of.  Oils highest in monounsaturated fats include safflower, olive and canola.

Polyunsaturated fats are good sources of omega-6 and omega-3 fatty acids. Most Americans don’t get enough omega-3s. Oils commonly used in cooking that have a good amount of omega-3s include soybean and canola.

It’s important to note that despite their heart-healthy traits, you shouldn’t overdo it on oils. The Dietary Guidelines for Americans recommends that most adults limit oils to 5 to 7 teaspoons a day. That includes oils in all foods, including nuts, peanut butter, olives, high-fat fish such as salmon or trout, avocados, mayonnaise and salad dressings, and margarine.