Time-restricted eating no better than counting calories, study finds | CNN

The Mediterranean diet is easy to find in the grocery store, contains nutrients that are known to enhance longevity and has other health benefits that are backed by peer-reviewed, scientific studies. Broccoli makes the list because it's one of nature's most nutrient-dense foods, with only 30 calories per cup. That means you get a ton of hunger-curbing fiber and polyphenols -- antioxidants that detoxify cell-damaging chemicals in your body -- with each serving.

Doctors suggest using olive oil rather than butter to make your meals. A Spanish study found a Mediterranean diet supplemented with extra-virgin olive oil reduced the incidence of major cardiovascular events among patients with a history of heart disease.

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Quinoa is the popular whole-grain du jour because it also contains a good dose of protein to help build muscle. Yet including any type of whole grain in your diet -- from barley to brown rice -- will aid in weight loss by filling you up for fewer calories.

Blueberries are often singled out as a kind of superfood because studies have shown they aid in everything from fighting cancer to lowering cholesterol. But all berries, including raspberries, strawberries and blackberries, contain antioxidants and phytonutrients. Worried about the price of fresh fruit? Experts say the frozen kind is just fine.

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Many dieters shy away from nuts because of their high calorie and fat count. But studies show that eating a handful several times a week can prevent heart disease and ultimately help you shed pounds since they fill you up and stop you from snacking on other things. Almonds, in particular, contain lots of monounsaturated fats and fiber. (Healthy swap: Replace peanut butter with almond butter.)

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Salmon is also a good source of lean protein. With this diet, doctors suggest eating fish at least two times a week. Salmon provides a high dose of omega-3 fatty acids, which studies show significantly lower the risk of heart disease. Omega-3 fatty acids fight back by reducing inflammation and slowing the rate of plaque buildup in blood vessels.

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Beans, beans, the magical fruit; the more you eat, the more ... you lose weight. Black, kidney, white and garbanzo beans (also known as chickpeas) are good for fiber and protein. They fill you up and provide muscle-building material without any of the fat that meat can add to your meal.

Eating a breakfast high in protein is a good way to keep hunger at bay throughout the day. Eggs are full of choline, a nutrient that helps block fat from being absorbed in the liver. Choline may also help in preventing memory loss.

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Spinach is a great source of iron, which is a key component in red blood cells that fuel our muscles with oxygen for energy. But researchers in Sweden identified another way in which these greens might keep you charged: Compounds found in spinach actually increase the efficiency of our mitochondria, the energy-producing factories inside our cells. That means eating a cup of cooked spinach a day may give you more lasting power on the elliptical machine (or in your daily sprint to catch the bus).

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Walnuts are packed with tryptophan, an amino acid your body needs to create the feel-great chemical serotonin. (In fact, Spanish researchers found that walnut eaters have higher levels of this natural mood-regulator.) Another perk: "They're digested slowly," said Dr. David Katz, director of the Yale Prevention Research Center. "This contributes to mood stability and can help you tolerate stress."

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Asparagus is one of the best veggie sources of folate, a B vitamin that could help keep you out of a mental slump. "Folate is important for the synthesis of the neurotransmitters dopamine, serotonin and norepinephrine," said David Mischoulon, associate professor of psychiatry at Harvard Medical School. All of these are crucial for mood.

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It's not a requirement to drink it on this diet, but if you do drink alcohol, red wine in moderate amounts can be good for your health. Moderation means one drink for women and two for men, by the way. Studies show red wine can help protect against heart disease.

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CNN —

In a blow to believers in time-restricted eating – a form of intermittent fasting where people only eat during a restricted window during the day – researchers in China have found the method has no significant benefits compared with simple calorie restriction in battling obesity.

“Our data suggest that caloric intake restriction explained most of the beneficial effects of a time-restricted eating regimen,” according to researchers at Southern Medical University in Guangzhou, China.

“Bottom line, the determinant of weight loss, as well as reductions in body fat, visceral fat, blood pressure, and glucose and lipid levels, is dependent on reducing calorie intake, regardless of the distribution of food and beverages consumed throughout the day,” said Alice Lichtenstein, director and senior scientist at Tufts University’s Cardiovascular Nutrition Laboratory, via email. She was not involved in the study.

The study, published Thursday in the New England Journal of Medicine, split 139 overweight to significantly obese adults in Guangzhou into two study groups that were followed for a year.

One group was told to limit their daily food intake to 1,500 to 1,800 calories a day for men, and 1,200 to 1,500 calories a day for women. Men and women in the other group were told to eat the same amount of calories, but to eat only between the hours of 8 a.m. and 4 p.m.

Time-restricted eating has no significant benefits compared with simple calorie restriction in battling obesity, a new study said.

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To track compliance, study participants were asked to keep food diaries and photograph all food they ate.

At the end of the year, both groups lost weight – about 14 to 18 pounds (6.4 to 8.2 kilograms) – but eating on a time-restricted schedule didn’t produce any significant difference in weight loss between the two groups.

Nor was there any real difference in other markers of weight loss, such as BMI (body mass index, a popular way of measuring weight), waist circumference, body fat or metabolic risk factors such as insulin resistance and blood pressure.

Prior research showed benefits

Prior research had shown advantages to time restriction. A 2020 review of human and animal studies had found benefits to restricting calories to a shortened period of the day, including a reduction in blood pressure, weight loss and improved longevity.

However, a number of those studies were in mice and those in humans were of much shorter duration, mere months.

The results of the year-long clinical trial are not surprising, said Dr. David Katz, a specialist in preventive and lifestyle medicine and nutrition, who was not involved in the study.

“Restricting time instead of calories does not contribute metabolic magic; rather, it is a form of discipline that helps to control calories,” said Katz via email.

“My favorite approach is to focus on the quality of foods and diet, and then let quantity control take care of itself. A diet made up mostly of whole, wholesome plant foods is intrinsically satiating at low calorie levels,” he said.

“Decisions on the approach used to restrict calorie intake should be determined by what works best for an individual within the context of their lifestyle,” said Lichtenstein, who is also a Gershoff Professor of Nutrition Science and Policy at Tufts University. “The most important factor is identifying an approach that is sustainable in the long term.”