Exercise Added to Diet Improves Weight Loss in Diabetes

MONTREAL — The focus of lifestyle interventions for type 2 diabetes should be on combining weight loss diets with exercise, according to new research.

Weight loss is similar for either high-carbohydrate (HC) or a high-protein (HP) diets—with the addition of exercise fueling the benefits of either diet, reported Thomas Wycherley at the World Diabetes Congress.

The study, which was partially funded by the Pork Cooperative Research Centre in Australia, showed a nonsignificant trend toward better outcomes in patients on an HP rather than HC diet—an observation that makes sense for certain patients, remarked Dr. Jim Mann, an endocrinologist who was not connected to the study.

“I think there is a reasonable body of evidence that a high-protein diet may have some benefits [over a high-carbohydrate diet] for some people with the metabolic syndrome because these people tend towards a lot of high-glycemic carbohydrates, which is not good,” Dr. Mann, a professor of human nutrition and medicine at Edgar National Centre for Diabetes Research in Dunedin, New Zealand, said in an interview.

Previous research has indicated that there is some evidence that during weight loss, consumption of a high-protein diet may potentiate the impact of resistance exercise, compared with a high-carbohydrate diet, Mr. Wycherley said.

His study compared HC and HP weight-loss diets, with and without a resistance training program, over 12 weeks in 83 men and women with type 2 diabetes, 59 of whom completed the study. The groups had similar dropout rates.

The subjects were a mean age of 56 years, with a mean baseline body mass index of 35. The diets were equally energy restrictive (6 MJ/day for women and 7 MJ/day for men) and equal in fat content (about 25%), said Mr. Wycherley, a research assistant at the University of Adelaide (Australia). The HC diet had 55% carbohydrate and 20% protein, with the goal of providing 0.8 g/kg per day of protein. The HP diet contained 40% carbohydrate and 35% protein with the goal of providing 1.2 g/kg per day of protein. Both diets consisted mainly of whole foods, with dairy, animal, and vegetable sources of protein, and whole grains rather than processed carbohydrates.

Overall, there was a mean weight loss of about 10 kg (10%) across all four groups. Subjects in the HC and HP groups lost a mean of 8.6 and 9.0 kg, respectively. However, for those who also attended exercise sessions three times a week, the weight loss was greater (10.5 kg for HC and exercise, and 13.8 kg for HP and exercise).

All treatment groups had similar improvements in traditional cardiovascular disease risk markers, with a 10% drop in both systolic and diastolic blood pressure, and drops of 0.47 mmol/L in triglycerides, 0.67 mmol/L in total cholesterol, and 0.37 mmol/L in LDL cholesterol.

Glycemic control also showed similar improvements in all groups, with a mean drop of 2.1 mmol/L in fasting glucose, 4.7 mU/L in serum insulin, and 1.25% in hemoglobin A_1c.

“This really does reiterate the importance of achieving dietary weight loss in this patient group,” Mr. Wycherley said.

Recent research has shown similar results of exercise and high-protein versus high-carbohydrate diets in nondiabetic subjects, he said, but until now this has not been studied in patients with diabetes.

“In response to the diabetes and obesity epidemic, we're seeing an increase in the prevalence of alternative diets such as high-protein diets. This has raised some conjecture in the literature regarding the optimal dietary composition to deliver the most therapeutic benefits to this patient group—in particular surrounding the carbohydrate to protein ratio,” he said.

Mr. Wycherley did not declare any relevant conflicts of interest.

MONTREAL — The focus of lifestyle interventions for type 2 diabetes should be on combining weight loss diets with exercise, according to new research.

Weight loss is similar for either high-carbohydrate (HC) or a high-protein (HP) diets—with the addition of exercise fueling the benefits of either diet, reported Thomas Wycherley at the World Diabetes Congress.

The study, which was partially funded by the Pork Cooperative Research Centre in Australia, showed a nonsignificant trend toward better outcomes in patients on an HP rather than HC diet—an observation that makes sense for certain patients, remarked Dr. Jim Mann, an endocrinologist who was not connected to the study.

“I think there is a reasonable body of evidence that a high-protein diet may have some benefits [over a high-carbohydrate diet] for some people with the metabolic syndrome because these people tend towards a lot of high-glycemic carbohydrates, which is not good,” Dr. Mann, a professor of human nutrition and medicine at Edgar National Centre for Diabetes Research in Dunedin, New Zealand, said in an interview.

Previous research has indicated that there is some evidence that during weight loss, consumption of a high-protein diet may potentiate the impact of resistance exercise, compared with a high-carbohydrate diet, Mr. Wycherley said.

His study compared HC and HP weight-loss diets, with and without a resistance training program, over 12 weeks in 83 men and women with type 2 diabetes, 59 of whom completed the study. The groups had similar dropout rates.

The subjects were a mean age of 56 years, with a mean baseline body mass index of 35. The diets were equally energy restrictive (6 MJ/day for women and 7 MJ/day for men) and equal in fat content (about 25%), said Mr. Wycherley, a research assistant at the University of Adelaide (Australia). The HC diet had 55% carbohydrate and 20% protein, with the goal of providing 0.8 g/kg per day of protein. The HP diet contained 40% carbohydrate and 35% protein with the goal of providing 1.2 g/kg per day of protein. Both diets consisted mainly of whole foods, with dairy, animal, and vegetable sources of protein, and whole grains rather than processed carbohydrates.

Overall, there was a mean weight loss of about 10 kg (10%) across all four groups. Subjects in the HC and HP groups lost a mean of 8.6 and 9.0 kg, respectively. However, for those who also attended exercise sessions three times a week, the weight loss was greater (10.5 kg for HC and exercise, and 13.8 kg for HP and exercise).

All treatment groups had similar improvements in traditional cardiovascular disease risk markers, with a 10% drop in both systolic and diastolic blood pressure, and drops of 0.47 mmol/L in triglycerides, 0.67 mmol/L in total cholesterol, and 0.37 mmol/L in LDL cholesterol.

Glycemic control also showed similar improvements in all groups, with a mean drop of 2.1 mmol/L in fasting glucose, 4.7 mU/L in serum insulin, and 1.25% in hemoglobin A_1c.

“This really does reiterate the importance of achieving dietary weight loss in this patient group,” Mr. Wycherley said.

Recent research has shown similar results of exercise and high-protein versus high-carbohydrate diets in nondiabetic subjects, he said, but until now this has not been studied in patients with diabetes.

“In response to the diabetes and obesity epidemic, we're seeing an increase in the prevalence of alternative diets such as high-protein diets. This has raised some conjecture in the literature regarding the optimal dietary composition to deliver the most therapeutic benefits to this patient group—in particular surrounding the carbohydrate to protein ratio,” he said.

Mr. Wycherley did not declare any relevant conflicts of interest.

MONTREAL — The focus of lifestyle interventions for type 2 diabetes should be on combining weight loss diets with exercise, according to new research.

Weight loss is similar for either high-carbohydrate (HC) or a high-protein (HP) diets—with the addition of exercise fueling the benefits of either diet, reported Thomas Wycherley at the World Diabetes Congress.

The study, which was partially funded by the Pork Cooperative Research Centre in Australia, showed a nonsignificant trend toward better outcomes in patients on an HP rather than HC diet—an observation that makes sense for certain patients, remarked Dr. Jim Mann, an endocrinologist who was not connected to the study.

“I think there is a reasonable body of evidence that a high-protein diet may have some benefits [over a high-carbohydrate diet] for some people with the metabolic syndrome because these people tend towards a lot of high-glycemic carbohydrates, which is not good,” Dr. Mann, a professor of human nutrition and medicine at Edgar National Centre for Diabetes Research in Dunedin, New Zealand, said in an interview.

Previous research has indicated that there is some evidence that during weight loss, consumption of a high-protein diet may potentiate the impact of resistance exercise, compared with a high-carbohydrate diet, Mr. Wycherley said.

His study compared HC and HP weight-loss diets, with and without a resistance training program, over 12 weeks in 83 men and women with type 2 diabetes, 59 of whom completed the study. The groups had similar dropout rates.

The subjects were a mean age of 56 years, with a mean baseline body mass index of 35. The diets were equally energy restrictive (6 MJ/day for women and 7 MJ/day for men) and equal in fat content (about 25%), said Mr. Wycherley, a research assistant at the University of Adelaide (Australia). The HC diet had 55% carbohydrate and 20% protein, with the goal of providing 0.8 g/kg per day of protein. The HP diet contained 40% carbohydrate and 35% protein with the goal of providing 1.2 g/kg per day of protein. Both diets consisted mainly of whole foods, with dairy, animal, and vegetable sources of protein, and whole grains rather than processed carbohydrates.

Overall, there was a mean weight loss of about 10 kg (10%) across all four groups. Subjects in the HC and HP groups lost a mean of 8.6 and 9.0 kg, respectively. However, for those who also attended exercise sessions three times a week, the weight loss was greater (10.5 kg for HC and exercise, and 13.8 kg for HP and exercise).

All treatment groups had similar improvements in traditional cardiovascular disease risk markers, with a 10% drop in both systolic and diastolic blood pressure, and drops of 0.47 mmol/L in triglycerides, 0.67 mmol/L in total cholesterol, and 0.37 mmol/L in LDL cholesterol.

Glycemic control also showed similar improvements in all groups, with a mean drop of 2.1 mmol/L in fasting glucose, 4.7 mU/L in serum insulin, and 1.25% in hemoglobin A_1c.

“This really does reiterate the importance of achieving dietary weight loss in this patient group,” Mr. Wycherley said.

Recent research has shown similar results of exercise and high-protein versus high-carbohydrate diets in nondiabetic subjects, he said, but until now this has not been studied in patients with diabetes.

“In response to the diabetes and obesity epidemic, we're seeing an increase in the prevalence of alternative diets such as high-protein diets. This has raised some conjecture in the literature regarding the optimal dietary composition to deliver the most therapeutic benefits to this patient group—in particular surrounding the carbohydrate to protein ratio,” he said.

Mr. Wycherley did not declare any relevant conflicts of interest.