Potato chips are piling on pounds, study finds

Blame the potato chip. It's the biggest demon behind that pound-a-year weight creep that plagues many of us, a major diet study found. Bigger than soda, candy and ice cream.

And the reason is partly that old advertising cliche: You can't eat just one.

"They're very tasty and they have a very good texture. People generally don't take one or two chips. They have a whole bag," said obesity expert Dr. F. Xavier Pi-Sunyer of the St. Luke's-Roosevelt Hospital Center in New York.

What we eat and how much of it we consume has far more impact than exercise and most other habits do on long-term weight gain, according to the study by Harvard University scientists. It's the most comprehensive look yet at the effect of individual foods and lifestyle choices such as sleep time and quitting smoking.

The results were published last month in the New England Journal of Medicine.

Weight problems are epidemic. Two-thirds of American adults are overweight or obese. Childhood obesity has tripled in the past three decades. Pounds often are packed on gradually over decades, and many people struggle to limit weight gain without realizing what's causing it.

The new study finds food choices are key. The message: Eat more fruits, vegetables, whole grains and nuts. Cut back on potatoes, red meat, sweets and soda.

"There is no magic bullet for weight control," said one study leader, Dr. Frank Hu. "Diet and exercise are important for preventing weight gain, but diet clearly plays a bigger role."

Doctors analyzed changes in diet and lifestyle habits of 120,877 people from three long-running medical studies. All were health professionals and not obese at the start. Their weight was measured every four years for up to two decades, and they detailed their diet on questionnaires.

On average, participants gained almost 17 pounds during the 20-year period.

For each four-year period, food choices contributed almost 4 pounds. Exercise, for those who did it, cut less than 2 pounds.

Potato chips were the biggest dietary offender. Each daily serving containing 1 ounce (about 15 chips and 160 calories) led to a 1.69-pound uptick during four years. That's compared to sweets and desserts, which added 0.41 pound.

For starchy potatoes other than chips, the gain was 1.28 pounds. Within the spud group, french fries were worse for the waist than boiled, baked or mashed potatoes. That's because a serving of large fries contains between 500 to 600 calories compared with a serving of a large baked potato at 280 calories.

Soda added a pound during four years. Eating more fruits and vegetables and other unprocessed foods led to less weight gain, probably because they are fiber-rich and make people feel fuller.

For each four-year period, these factors had these effects on weight:

An alcoholic drink a day: 0.41-pound increase

Watching an hour of TV a day: 0.31-pound increase

Recently quitting smoking: 5-pound increase

People who slept more or less than six to eight hours a night gained more weight.

The study was funded by the National Institutes of Health and a foundation. Several researchers reported receiving fees from drug and nutrition companies.

"Humans naturally like fat and sweet," said Dr. David Heber, director of the UCLA Center for Human Nutrition, who had no role in the study. "That's why we always tell people to eat their fruits and vegetables."

Pi-Sunyer, who also wasn't involved in the research, said the study gives useful advice.

"It's hard to lose weight once you gain it," he said. "Anything that will give people a clue about what might prevent weight gain if they follow through with it is helpful."

The federal government earlier this year issued new dietary guidelines advising people to eat smarter. This month, it ditched the food pyramid -- the longtime symbol of healthy eating -- in favor of a dinner plate divided into four sections containing fruits, vegetables, protein and grains.

Nuts instead of carbs may aid diabetes control: study

(Reuters Life!) - Replacing that daily muffin with a handful or two of nuts may help people with diabetes better control their blood sugar and cholesterol levels, according to a study.

When people with type 2 diabetes replaced some of their usual carbohydrates with about a half-cup of mixed nuts each day, their blood sugar and "bad" cholesterol levels dipped slightly over three months, researchers wrote in the journal Diabetes Care.

By contrast, no such improvements were seen among people who swapped their normal carbs for a daily whole-wheat muffin.

While the findings don't mean that nuts are the key to diabetes control, they can be part of a healthy diet, said Cyril Kendall of the University of Toronto in Canada, one of the researchers involved.

"We should be focusing on overall diet and lifestyle," Kendall told Reuters Health.

"They (nuts) have a lot of fat, but we now realize that those fats are healthy ones," he said, referring to the unsaturated fats that have been linked to a lower risk of heart disease and other health benefits.

Still, nuts are high in calories, and people with diabetes should not simply add a handful to their usual diet but should use them in place of less healthy snacks, Kendall said.

For the study, 117 adults with type 2 diabetes were randomly assigned to one of three groups. One group was given unsalted mixed nuts and told to eat them instead of some of their usual carbs, a second group replaced their normal carbs with "healthy" whole-wheat muffins with no added sugar, and the third group went on a half-nut, half-muffin regimen.

The "full-nut" group ate, on average, about 2 ounces, or a half cup, of nuts per day, totaling roughly 475 calories.

After three months, the researchers found, the full-nut group showed a 0.2 percent dip in their average hemoglobin AIC level -- a measure of long-term blood sugar control.

The change was small and "just shy," Kendall said, of what is considered a clinically significant improvement in blood sugar control. But the people in the study were already on diabetes medication and typically had good blood sugar control.

"So we're seeing a benefit over and above what they were achieving with medication," he added.

As for cholesterol, the nut group's average LDL cholesterol -- the "bad" kind -- declined from about 97 milligrams per deciliter to 89 mg/dL. An LDL count below 100 mg/dL is generally considered optimal.

No similar improvements were seen in the other two groups.

It wasn't clear why the full-nut group showed better blood sugar and cholesterol levels, but Kendall said he suspects it is largely because of the monounsaturated fats in nuts.

For people who aren't crazy about nuts, there are other sources of monounsaturated fats, such as olive oil and avocados. While the study did not look at those foods, Kendall said it might be a wise move to replace some carbs with those fats.

The study was partially funded by the International Tree Nut Council Nutrition Research & Education Foundation and the Peanut Institute, both industry groups. SOURCE: bit.ly/pwmyBV

(Reporting by Amy Norton at Reuters Health; editing by Elaine Lies)