10 Things We’ve Learned About Fat

Experts have long known that trans fat isn’t good for us, but research has turned up surprises—chocolate and chili peppers can help us lose fat

Flickr user Renée S. Suen

It wasn’t much of a surprise last week when the Food and Drug Administration (FDA) announced that it’s about to drop the hammer on trans fat—the by-product of the process of adding hydrogen to vegetable oil, which brings taste and texture to a bunch of food that’s not so good for us.

Yes, in the future, doughnuts may be a bit oilier, microwave popcorn could go back to popping in butter and manufacturers of frozen pizzas will need to find another additive to keep them reasonably edible. But the FDA has had its eye on trans fat since the 1990s, when the agency first proposed that nutrition labels disclose how much of the artificial fat is inside. That didn’t happen until 2006, which was the same year New York Mayor Michael Bloomberg declared war on trans fat. Two years later, a ban on trans fat in the city’s restaurants kicked in.

tray of doughnuts

With trans fat going away, doughnuts may taste a little different. Photo courtesy of Flickr user sea turtle

The reason, of course, is that it’s a notorious artery-clogger, one with a double negative of decreasing good cholesterol and raising bad cholesterol.

But, as we say a not so fond farewell to trans fat, researchers keep finding out new things about fat, whether in our food or in our bodies. Here are 10 things they’ve learned so far this year:

1) Let’s start with the good news: Chocolate may actually help reduce a person’s abdominal fat. According to a European study published in the journal Nutrition, teenagers who eat a lot of chocolate tend to have smaller waists. Even though chocolate contains sugar and fat, it also is high in flavonoids–particularly dark chocolate–and they’ve been found to be good for your health.

2) But wait, there’s more: A team of scientists in Japan determined that both cold weather and chili peppers can help burn fat. Specifically, exposure to cold temperatures and consumption of the chemicals found in the hot peppers appear to increase the activity of “brown fat” cells, which burn energy, instead of storing it as “white” fat cells do.

3) On the other hand: Low-fat yogurt may be more fattening than we’ve been led to believe, at least according to researchers behind a project called the Nutrition Science Initiative. They contend that easily digested carbohydrates—such as the sugars that are added to low-fat yogurt to replace the fat that has been removed—drive weight gain by promoting insulin resistance. This signals the body to convert more sugar into fat and to hold on to more of the fat in the food.

4) Ah, the vicious circle: Based on research with mice, scientists say that one reason people can have such a hard time switching to a healthier diet is that high-fat diets can interfere in the communication between the gut and the brain’s reward center. And that can make people think they need to eat more to feel satisfied.

5) So belly fat drains the brain?: Middle-aged people with a lot of belly fat are more than three times as likely to have memory problems and suffer from dementia when they’re older, according to researchers at the Rush Medical Center in Chicago. It turns out that both the liver and the hippocampus–the brain’s memory center–need the same protein, and the more the liver uses to burn abdominal fat, the less that’s available to the brain.

6) And saturated fats lower sperm counts?: Scientists in Denmark found that young men who ate a lot of food high in saturated fat, such as rich cheeses and red meat, had a significantly lower sperm count than men who ate low levels of fat. The researchers said that might help explain why sperm counts are dropping around the world.

7) Then again, maybe saturated fats aren’t so evil: A British cardiologist says his research suggests that saturated fats aren’t as bad as they’re made out to be, and that the crusade against them has driven people to low-fat foods and drinks full of sugar. In a recent issue of the British Medical Journal, Aseem Malhotra wrote: “It is time to bust the myth of the role of saturated fat in heart disease and wind back the harms of dietary advice that has contributed to obesity.”

8) Fat and taxes: Another British study contends that a 20 percent tax on sodas could reduce obesity in the U.K. by 180,000 people. About one in four Britons is obese, just slightly lower than the U.S. The researchers believe the tax could reduce soda sales by as much as 15 percent and would have the greatest impact on people under 30, who are more likely to guzzle sugary drinks.

9) Taking one for the team: Here’s something you’ve probably always suspected: When a sports fan’s team loses, he or she tends to scarf down a lot of high-fat food. That’s the conclusion of a study published recently in the journal Psychological Science, which found that football fans’ saturated-fat consumption increased by as much as 28 percent following defeats and decreased by 16 percent following victories. As Pierre Chandon, one of the study’s co-authors, told the New York Times, “No one ate broccoli after a defeat.”

10) Yes, bacon rules: A comprehensive analysis by Wired.com of all of the recipes and comments on the Food Network’s website determined that meals that include bacon tend to be more popular than those with any other food. Based on its data-crunching, Wired.com found that the only foods that people felt didn’t go better with bacon were pasta and desserts.

Video bonus: Here’s a rundown of some foods that owe a lot of their popularity to trans fat.

Video bonus bonus: And how could the subject of trans fat be broached without paying homage to the greatest doughnut lover of all.

More on Smithsonian.com

Why a Simple Message–Fat Is Bad–Is Failing

10 New Things We Know About Food and Diets

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