Studies identify hallmarks of effective weight loss diets for people with prediabetes

Three randomised trials of obese participants with prediabetes or type 2 diabetes suggest that wholesomen, high fibre diets of vegetables and low glycemic load or low-carb foods is best for weight maintenance.
Researchers used two biomarkers in order to define what a good weight-maintenance diet may be for people with type 2 diabetes or prediabetes.
The researchers, from the University of Copenhage, announced in findings published in the AJCN journal that those biomarkers were fasting blood sugar and/or fasting insulin.
“Recognising fasting glucose as a key biomarker enables a new interpretation of the data from many previous studies, which could potentially lead to a breakthrough in personalized Nutrition,” according to Head of Department, Arne Astrup.
Now that these data sets are collected, the plan is to keep expanding the list of biomarkers with additional ones for things like the gut microbiome or genomics.
Between the Diet, Obesity, and Genes (DiOGenes) trial, the OPUS Supermarket intervention (SHOPUS) trial and the Nutrient-gene interactions in human obesity (NUGENOB) trial, researchers already analysed data on more than 1,200 individuals.
The different studies looked at relationships between those biomarkers and weight under caloric restriction and ad libitum diets, with varying contributions of carbs and fat, and fibre intake.
They found that those with prediabetes in the ad libitum DiOGenes trial regained significantly more weight (5.83 kg) on the high– than on the low–glycemic load diet after 26 weeks.
In SHOPUS, also ad libitum, people with prediabetes lost a mean of six kilos in 26 weeks with the New Nordic Diet, which is higher in fibre and whole grains.
Finally, in the 10 week-study NUGENOB, people with diabetes lost a mean of 2.04 kg more on a calorie restricted high-fat, low-carb diet than on its isocaloric low-fat, high-carb counterpart.
In terms of biomarkers, overweight or obese participants with elevated fasting glucose were found to be four times more susceptible to weight regain when consuming a high–glycemic load diet.
Fasting insulin on its own did not turn out to be such a good biomarker. However, when combined with fasting glucose, it further strengthened all of these associations.
Participants with low fasting glucose and high fasting insulin responded equally on all diets, whereas those with high fasting glucose and low fasting insulin did better on diets with a lower glycemic load and more fibre.
Overall, there seems be a larger weight loss among people with diabetes on a high-fat, low-carb diet. As for people with prediabetes, it is a diet with a low glycemic load or high in fibre that is the clear winner.