- Those assigned to intermittent fasting over a 16-week period lost weight and improved their blood sugar control significantly with metformin or empagliflozin, two commonly prescribed diabetes medications.
- The study focused on the 5:2 type of fasting, in which people eat normally for five days a week and then fast for two days, eating only 500 to 600 calories during their fasting period.
- After 16 weeks, the fasting group lost an average of 21 pounds, almost double the 12 pounds lost by the average metformin group. Those prescribed empagliflozin lost an average of 12.8 pounds during the study.
- Previous studies We looked at whether intermittent fasting could help people with type 2 diabetes, but because they were mostly small, they didn’t compare the diet to drugs.
- The study included more than 330 overweight and obese adults with recent type 2 diabetes.
Courtney PetersonAn expert who was not involved in the study said the results were “exciting”.
“We often think that drugs are more powerful than lifestyle changes,” said Peterson, an associate professor of nutritional science at the University of Alabama at Birmingham. But here people have shown that lifestyle is more effective in lowering blood sugar than taking drugs. This is a very powerful statement.
The 5:2 diet was first popularized over a decade ago in a BBC documentary and best-selling book, “Fast foodBy British physician Michael Mosley with co-author Mimi Spencer.
The new 5:2 Diet study was conducted in China, which has more people with type 2 diabetes than any other country in the world. At least 141 million adults in China have diabetes, and half of the population is overweight or obese.
The authors of the new study recruited adults with type 2 diabetes and divided them into three groups. In the first two groups, participants were assigned to receive metformin or empagliflozin. In the third group, participants were taught to follow a 5:2 diet. Women eat just 500 calories on each of their two weekly fasting days, while men eat no more than 600 calories — about a quarter of their usual calorie intake.
During their fast, participants ate relatively few meals: an egg for breakfast, a serving of vegetables or fruit for lunch, and a light salad for dinner. Each meal is paired with a low-calorie meal replacement drink that contains healthy fats, protein, vitamins, minerals and other nutrients. On non-fasting days, participants eat normally for breakfast and lunch, followed by a light dinner with a meal replacement drink.
In addition to losing weight, the fasting subjects had a 1.9 percent drop in HbA1c, a measure of blood sugar — significantly more than the medication group. About 80 percent of those in the fasting group saw their HbA1c drop below 6.5 percent, a reduction in diabetes, compared with 60 percent of those taking metformin and 55 percent of those taking empagliflozin.
Eight weeks after the end of the study, the researchers followed up with the participants and found that most people in the fasting group maintained their blood sugar levels below the threshold for diabetes, suggesting that the diet “significantly and sustainably improved HbA1c levels,” the authors wrote.
The researchers found that the fasting group had significantly lower waist circumference, blood pressure, and triglycerides, a type of fat that circulates in the blood, compared to the participants.
The researchers cautioned that more studies are needed to test the long-term effectiveness of the 5:2 diet as a meal replacement for type 2 diabetes. But their findings suggest that the diet may be a good first lifestyle choice for people with early stage diabetes.
Fasting combined with meal replacement
Peterson said the study was large, rigorous and smartly designed because it essentially looked at two dietary interventions — intermittent fasting and meal replacement — to help people with diabetes.
Many studies Diets that include low-calorie meal replacement shakes, soups, and bars have found that they help people lose weight and lower blood sugar. Many studies They also indicated that the 5:2 diet helps people improve their blood sugar control.
Peterson said one of the downsides to the 5:2 diet is that people see amazing results in the first few months, but after six months to a year of being on the diet, they “start to fall off.”
“It seems to be beneficial in the short term, but in the long term, a year or more, it doesn’t seem any better than a regular low-calorie diet,” she added.
They also stressed the need for more long-term research. But in the meantime, she said, people with newly diagnosed type 2 diabetes may want to consider combining the 5:2 diet with a meal replacement such as Optifast, Insure, Soylent or others to discuss with their doctor.
Although the participants in the study did not experience many adverse events during the fasting regime, about 6 percent of the people on the diet reported symptoms of low blood sugar, which can be dangerous, she said.
“If people want to try this, they should absolutely work with their doctor,” Peterson said. “They shouldn’t try it on their own.”
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