What does saturated fat cause? Arguments.

Farmhouse aged Gouda. Farmhouse aged Gouda. (Pam Berry/Globe Staff/File)
By Allison Boomer
Globe Correspondent / February 24, 2010

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The creamy soft-ripened Camembert looks good today. So does the butterscotch-flavored aged Gouda. And there’s nice whole-milk yogurt, steak with a little fat around the edge, rotisserie chicken with golden skin, and smoky thick-cut bacon. Many consumers see these foods and head in the other direction. They are part of that large group plagued by our prevailing food obsession, what the late Julia Child called “fear of fat.’’

For the past 40 years, well-meaning specialists have told Americans that eating saturated fat is bad for heart health. It now appears that conventional wisdom is on shaky ground. Last month’s American Journal of Clinical Nutrition published a landmark study from the Harvard School of Public Health and the Children’s Hospital Oakland Research Institute that has turned current fat recommendations upside down. The verdict from the study is that “there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk for heart disease.’’ Equally important, we are learning that restricting fat intake is not without serious health consequences, such as escalating rates of obesity and diabetes. The report evaluates dietary data from a total of 347,747 subjects from eight countries in 21 studies, over 25 years.

Not everyone agrees with the study’s results. Lalita Kaul, a spokeswoman for the American Dietetic Association and professor of nutrition at Howard University, says that although she is open to changing viewpoints as new studies come to light, she still believes saturated fat is one of many factors that cause heart disease. “I would not advise patients to eat more saturated fats based on this study.’’

Dr. Ronald Krauss, the study’s principal investigator and director of atherosclerosis research at Children’s Hospital Oakland Research Institute, says, “It’s time to turn the page on how we perceive saturated fats in relation to risk for heart disease. It’s the wrong message that saturated fats are artery-clogging or evil.’’ Krauss says any dietary recommendations to further reduce saturated fat would be of no benefit. Americans, he says, shouldn’t be avoiding all forms of saturated fats and it’s erroneous to focus on saturated fat out of context from the whole diet.

Although cheese, whole milk, beef, poultry, and pork all contain some saturated fat, these foods also contain a diverse mixture of other fats, including monounsaturated (found in olive oil and nuts) and polyunsaturated (found in vegetable oils). For example, roast beef has equal amounts of saturated and monounsaturated fat, while chicken and bacon fat are a blend of all three fats with, surprisingly, more monounsaturated than saturated. This varied mixture of fats may be why saturated fats are not necessarily bad for you.

In addition, high rates of obesity and Type 2 diabetes, especially in children, are one of the United States’ biggest public health concerns, an epidemic that happens to parallel decades of public health messages warning Americans that eating saturated fat is bad. As a result, many consumers instead eat commercially made low-fat confections that are full of sugar and high-fructose corn syrup. Eating too many of these calories can result in abnormal levels of blood sugar and triglycerides. These are well-established risk factors for obesity, diabetes, and heart disease. The question now is whether those efforts to lower dietary fat have caused a whole new set of chronic disease problems.

Reading food labels to gauge the amount of saturated fat in a product is putting the emphasis in the wrong place, says Dale E. Bauman, a professor of nutritional biochemistry at Cornell University. Consumers need to focus on total calories, he writes in an e-mail. “In hindsight the American Medical Association’s recommendation that caused people to stop eating butter and switch to margarine (high trans fatty acids) was tragic given our current knowledge of the clear and substantial health risks from consuming industrial trans fats.’’

Bauman thinks that consumers were told to push aside naturally occurring saturated fats, which he regards as healthful, in favor of foods with trans fats. Trans fats, also known as hydrogenated fats, use a process that changes a fat’s chemistry; in one instance, liquid vegetable oil becomes solid margarine. Trans fats raise “bad’’ (LDL) cholesterol and lower “good’’ (HDL) cholesterol, which increases risk for heart disease. Bauman thinks that with the exception of trans fats, the kind of fat you eat isn’t as important as eating all foods in moderation.

Adding a little healthy fat back into our diets can actually help curb sugar cravings and provide valuable nutrients. But that means feeling OK about eating fat, which might take getting used to. Krauss offers this: “There is no evidence that cheese causes heart disease.’’ But look at that ripe Camembert, and for many it’s hard not to think “bad fat.’’

Here are some breakfast comparisons: 1 cup nonfat fruit-flavored yogurt usually contains 233 calories and 46 grams of sugar. An alternative is to top 1 cup whole-milk yogurt with 1 cup unsweetened frozen berries. You still get 230 calories, but the sugar drops to 24 grams. That extra bit of fat in whole milk yogurt tastes good and provides a lot of satiety. It might just keep you from grabbing a muffin (about 440 calories, 30 grams of sugar) at midmorning.

Politicians, it seems, aren’t the only flip-floppers. The conflicting viewpoints of dietary specialists on the matter of fat can be like a ping-pong game. One carried out over decades, and still going.