Each year, millions of us go on diets in an attempt to lose weight, but not all of us succeed. A new study has uncovered two biomarkers that could predict how effective certain diets will be for weight loss, particularly for people prediabetes or diabetes.
From an analysis of more than 1,200 adults, researchers found that a person's fasting blood glucose levels, fasting insulin levels, or both, were effective for pinpointing which diets were most likely to lead to weight loss.
Such biomarkers were especially effective for determining which diets were best for people with prediabetes and diabetes, the researchers report.
Study co-author Dr. Arne Astrup, head of the Department of Nutrition at the University of Copenhagen in Denmark, and colleagues recently published their findings in the American Journal of Clinical Nutrition.
According to the American Diabetes Association, around 29.1 million people in the United States have diabetes.
Type 2 diabetes is the most common form of the condition, wherein the body is unable to effectively use the hormone insulin, causing high blood glucose levels.
Prediabetes is a condition in which blood glucose levels are higher than normal, but they are not high enough to warrant a diabetes diagnosis. However, people with prediabetes are at significantly greater risk of developing type 2 diabetes than those without prediabetes.
It is estimated that around 86 million people in the U.S. have prediabetes, but around 90 percent are unaware of it.
Diet and diabetes
According to the Centers for Disease Control and Prevention (CDC), for people with prediabetes, losing around 5 to 7 percent of their body weight and increasing exercise levels can reduce the risk of type 2 diabetes by as much as 58 percent.
For people who have already been diagnosed with diabetes, losing weight through diet and exercise can aid blood glucose control and lower the risk of other health conditions.
But which type of diet is most likely to achieve weight loss? It goes without saying that there is no one-size-fits-all approach to dieting. However, Dr. Astrup and colleagues believe that a person's fasting blood glucose and insulin levels could be used to help identify the most effective diet for weight loss.
To reach their conclusion, the researchers analyzed the data of three dietary clinical trials: the Diet, Obesity, and Genes trial, the OPUS Supermarket intervention (SHOPUS), and the Nutrient-gene interactions in human obesity (NUGENOB) trial.
In total, the study included the data of more than 1,200 adults, all of whom were overweight.
The researchers looked at the fasting blood glucose levels and fasting insulin levels of each participant, and they assessed whether these levels were associated with weight loss in response to certain diets.
A 'breakthrough in personalized nutrition'?
Among adults with prediabetes, the team found that a diet rich in whole grains, fruits, and vegetables was most effective for weight loss.
As an example, in the SHOPUS trial, adults with prediabetes who followed the New Nordic Diet - which is high in whole grains, fruits, and vegetables - lost a mean of 6.06 kilograms more weight over 26 weeks, compared with those who followed a control diet. Adults with normal blood glucose levels lost around 2.20 kilograms with the New Nordic Diet.
For people with type 2 diabetes, the researchers found that a diet rich in plant-based, "healthy" fats and low in carbohydrates was best for weight loss.
In the NUGENOB trial, for example, adults with type 2 diabetes lost around 2.04 kilograms more over 10 weeks on a diet that was high in plant-based fats and low in carbohydrates, compared with those whose diet was low in fat and high in carbohydrates. The high-fat, low-carbohydrate diet was better for weight loss among adults with normal blood glucose levels.
Adding participants' fasting insulin levels to their analysis further strengthened the identified associations between diet and weight loss, the team reports.
Based on their results, the researchers believe that fasting blood glucose and fasting insulin levels may be biomarkers for weight loss.
"Recognizing fasting plasma 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."
Dr. Arne Astrup
"The beauty of this concept is its simplicity. While we are looking into other biomarkers, it is quite amazing how much more we can do for our patients just by using those two simple biomarkers," adds Dr. Astrup.
"We will continue to participate in and support research to explore additional biomarkers such as gut microbiota and genomics approaches, which may offer more insights and help to more effectively customize the right diet for specific individuals."