Processed foods make you "stop"

Finishing food
makes
you "stop"
factors in the food processing process make people more likely to overeating. Even if both diets contain the same available calories and nutrients, people will gain more weight by eating more processed foods than unprocessed foods, according to a new study.
scientists have long suspected that increased consumption of processed foods over the past 50 years is the main cause of the obesity epidemic. But because of the complexity of eating habits research, it is difficult to directly link it to obesity.
recently, researchers published the results of a randomized controlled trial in Cell-
Metabolism
, which for the first time directly compared the differences in the effects of refined and unprocessed foods on calorie intake and weight gain. The study found that even if the
carbohydrates
,
fat
s, sugars, salts and calories in both diets were similar, people who ate refined foods would still eat more and gain weight.
Steven Heymsfield, an obesity researcher at Louisiana State University's Pennington Biomedical Research Center, said the study was "a landmark start" and a wake-up call to the health debate over processed foods.
Tiffany Weir, of the Department of Food Science and Human Nutrition at Colorado State University, told China Science that healthy eating has been controversial since nutrition emerged as a scientific discipline, but there is a awareness that the quality of the diet should be improved and that the intake of processed foods, including sugar and refined grains, should be improved.
processed food
.The definition of "processed food" is controversial. Almost all foods in the grocery store are processed: pasteurization, vacuum sealing, cooked, frozen, fortified, and added preservatives and flavoring agents. Some of these processes can change the nutritional quality of the food itself.
have found a link between processed foods and an increased risk of obesity, cancer and even earlier death, but none has shown a causal link.
, some health officials and governments still blame processed foods for the global obesity and related disease epidemic. Brazil's official dietary guidelines, for example, advise people to "limit the consumption of processed foods".
, however, processed foods seem to have magic that makes people eat "can't stop."
"I was very surprised by the findings of this study. Because I think refined foods don't make people eat more if they have the same amount of sugar, fat, carbohydrate, protein and sodium in both diets. "In fact, we found that people who ate refined foods consumed more calories, which increased their weight and body fat," said Kevin Hall of the National Institute of Diabetes, Digestive and Kidney Diseases. The
20 healthy volunteers
a one-month trial after eating two meals. For the first two weeks, each participant will eat one of the refined or unprocessed foods and the other for the next two weeks. Participants ate three meals a day, drank bottled water every day, and ate refined or unprocessed snacks. The researchers told participants how much they ate and recorded how much they ate.
researchers developed both diets using the NOVA Food Classification System, which classifys foods according to their degree of processing and purpose. For example, a finished breakfast includes honey nut wheat rings, fiber-added whole milk, packed blueberry muffins and margarine, while an unprocessed breakfast is raw Greek yogurt, barphy and apple slices made from strawberries, bananas, walnuts, salt and olive oil with freshly squeezed lemon juice. Participants were very satisfied with both diets, which ruled out participants' food preferences.
, participants consumed an average of 508 more calories per day and gained an average of two pounds in two weeks compared to unprocessed foods. For two weeks of eating unprocessed foods, participants lost an average of two pounds. The researchers said the results showed that refined foods increased participants' body fat, while unprocessed foods reduced their body fat.
metabolic tests showed that when eating refined foods, participants consumed more energy than they ate unprocessed foods, but not enough to offset their extra calorie intake. Because the participants were healthy and the test duration lasted only a month, the researchers found no significant differences in other health indicators, such as liver fat or blood sugar.
is the "magic"
why do those who eat refined food eat more?
when people eat refined food, they eat faster. "It's possible that certain textures or sensory properties of food make them eat faster." "If you eat too fast, you probably don't give your gastrointestinal tract enough time to signal to your brain that you're full," Hall said. In this case, you may overe eat.
Louise M. Burke, of the Maquili Institute of Health at the Australian Catholic University, told China Science that the oral cavity and its physical abilities communicate with different areas of the brain, such as when the mouth/throat comes into contact with carbohydrates, which activates the "reward center" in the brain, providing a sense of well-being and "energy." Eating too fast may not give the brain enough time to react.
other hypothesis is related to the role of solid foods and beverages. To balance dietary fiber and match the calorie density of the overall diet, the researchers added beverages, such as fiber juice and lemon juice, to the refined dietary diet. But some researchers don't think drinks produce the same feeling of satiety as solid foods. As a result, solid foods with higher calorie density in refined diets lead to an increase in total calorie intake.
, a researcher on dietary behavior at Pennsylvania State University, points out that super-processed foods tend to have higher energy density and contain more calories per g. The Rolls team found that the more high-energy foods, the more calories people consume because they tend to eat the same weight or volume of food each day.
, although the two dietary components were close, unprocessed foods contained slightly more protein, about 15.6 percent of the calories, compared with 14 percent of the calories in refined foods.
, some researchers don't see processing as a threat in itself. "In this study, a lot of super-processed foods may be that we shouldn't be eating too much." "But without processed foods, I don't think we're going to be able to feed the current population," Rolls said. In
, some experts say the study has an important limitation: all foods are prepared for participants, without taking into account their difficulty and cost of making them.
next step, the researchers will try to explain these possible factors and explore possible mechanisms for increased calorie intake. Hall et al. are planning a similar study: increasing the protein content of super-processed foods and swapping fiber-rich drinks for soups, which may encourage people to eat more slowly.
"We know that there are many reasons why people choose refined foods over unprocessed foods. Especially for people with lower socio-economic levels, we need to pay attention to the skills, equipment, knowledge and costs required to make unprocessed food. Hall said.
related paper information: .