A dose of reality on the dietary fat issue

With the Mediterranean diet all the rage, not only because consumers like its tasty composition but because of research touting its health benefits, experts have had to become more specific about recommendations for fats.

There’s a steady drumbeat these days — from everyone from chefs to food writers to health gurus — criticizing nutritionists and the “diet police,” who, they claim, told consumers to avoid fats and keep everything fat-free.

This makes for good hype, but I know of not one registered dietitian/nutritionist or any respectable and knowledgeable physician — not a single one — who ever said that. Ever.

A dose of reality on the dietary fat issue

The prevailing recommendation was to limit total fats to about 30 percent of calories (not too shabby) and saturated fats to about 10 percent of calories, because research showed that saturated fats, present in meat, full-fat and reduced-fat dairy foods and coconut and palm oils, seemed to hike bad cholesterol. The American Heart Association took this position after looking at both clinical research and observational studies of large populations. Those studies showed a correlation between a high intake of saturated fats and heart disease. That doesn’t mean cause and effect, so take it for what it is — a hypothesis.

Then we discovered trans fats, or “partially hydrogenated vegetable oils.” Evidence came out that for heart disease, they were as bad as or worse than saturated fats. The association was there, but only if more than about 3 percent of your calories came from trans fats. Among consumers, it’s not widely known that trans fats differ from one another. There are two types: manufactured trans fats, commonly used to extend the shelf life of prepared food, and natural trans fats, which occur in many dairy products and meats and have no known negatives.

Indeed, there’s some emerging evidence that natural trans fats such as conjugated linoleic acid may have some protective effects. Either way, consumers wanted added trans fats out of their food, and the food industry removed them.

About saturated fats: It’s complicated

Then the Mediterranean diet came along and showed that higher-fat diets that had lots of monounsaturated fats, such as olive oil, almonds and walnuts, had strong associations with great heart health. Everyone took out the extra-virgin olive oil and the nutcrackers and did a happy dance.  Even dietary guidelines for Americans eased up on fat allowance — up to 35 percent of calories — still, however, favoring monounsaturated fats.

It gets even more complicated. Not all saturated fats are equal. Some have a neutral effect on cholesterol. Stearic acid is a saturated fat that doesn’t have much effect at all on serum cholesterol. It’s found in beef, but it’s also the primary saturated fat in chocolate. This may be why the PREDIMED study — one of the larger studies of the Mediterranean diet — suggests no particular limit on dark chocolate. And the darker the better. (I love this kind of research news!)

Now there’s an emerging thought in the scientific community that we need to have a closer look at saturated fats overall, and that maybe the strict limits on them can be loosened.

Being frank about fats

Clearly, the whole subject can be quite confusing. Here’s how I’ve typically addressed the issue of fats and saturated fats with my patients and their parents at the nutrition clinic of Einstein’s Children’s Evaluation and Rehabilitation Center: Nothing is forbidden, and any food you like can fit. The issue is how much and how often.

For most people it’s about eating smaller amounts, less often. The first thing we do is address where the excesses are in their diets by taking a dietary history. Sometimes it is revealed that their excesses are in other areas. Maybe it’s not cheese or sausages but sweets and baked goods, which people may think are just sugary; most of the calories in these foods, though, come from fats, and they have little going for them nutritionally.

Understand that I see all type of nutrition conditions, so sometimes when I’m seeing a child with failure to thrive or an adult who is severely underweight, the typical rules change. There are times when I recommend cheese and French fries because the patient can eat only small amounts of food and may have high calorie needs. These instances are rare, to be sure, but nutrition is not a one-size-fits-all science and it’s critical to know when to use each tool you have available.

That’s why, when it comes to saturated fats or any confusing dietary issues, it can help to return to common sense.

Foods with saturated fats are essentially whole foods that have stood the test of time. Remember that consumption of these foods by our ancestors was accompanied by a much more physically active lifestyle. If you want to keep these types of foods prominent in your diet, keep our ancestors’ level of activity in your life as well.

If you’re not plowing forty acres of farmland or doing hard labor every day, cut back a bit on the saturated fats.

Keith-Thomas Ayoob is director, nutrition clinic, Children’s Evaluation and Rehabilitation Center, Albert Einstein College of Medicine, Bronx, NY. He blogs at The Doctor’s Tablet.

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