October 07, 2022
3 minute read
Jenkins reports receiving research grants from the Pulse Growers Associations of Saskatchewan and Alberta. Please see the study for relevant financial information from all other authors.
A low-carb vegan diet has similar health and environmental benefits compared to a vegetarian diet, a study reports.
Although low-carb diets like the Atkins diet have been promoted for weight loss and the treatment of type 2 diabetes, David Jenkins, MD, Ph.D., D.Sc.FRCPC, professor in the Department of Nutritional Sciences at the University of Toronto, and his colleagues wrote in Jhe American Journal of Clinical Nutrition that the Atkins diet is “not now generally advocated in its original form because it is a diet high in red meat and saturated fats of animal origin”.
“However, the diet’s original low-carb goals continue to be popular as ‘paleo’ and ‘keto’ diets,” they wrote, a trend that led them to develop an Atkins-like diet with a vegan design.
Jenkins and colleagues’ hybrid diet included enriched canola bread and high-protein simulated meat products. They compared the diet’s effectiveness with a vegetarian diet that focused on fruits, vegetables and low-fat dairy products while avoiding meat and snack foods. The researchers also assessed the potential effects of diets on greenhouse gas emissions by analyzing their environmental impacts on agriculture, food processing and transportation, which are “increasingly recognized in dietary guidelines international”.
The study included 164 participants with type 2 diabetes, who were randomly assigned to each diet for 3 months. Among them, 70 of 83 participants (84%) followed the low-carb vegan diet and 68 of 81 (84%) followed the vegetarian diet.
To be eligible, participants had to have a history of type 2 diabetes for at least 6 months, be on a stable dose of antihyperglycemic agents for at least 1 month previously, not be on insulin therapy, and have HbA1c values between 6 .5% and 8.5%.
Jenkins and colleagues found that the low-carb vegan diet (-5.9 kg; 95% CI: -6.55, -5.28 kg) and the vegetarian diet (-5.23 kg; at 95%: -5.84, -4.62 kg) produced similar results. reductions in body weight.
Participants who were assigned to the low-carb vegan diet had a 4.12 mmHg (95% CI, -6.65 to 1.59) reduction in systolic BP, while participants on the vegetarian diet saw a decrease of 5.91 mmHg (95% CI, -8.45 to -3.38). Diastolic BP decreased by 3.54 mmHg (95% CI, -5.29, -1.8) and 4.13 mmHg (95% CI, -5.89, -2.38) in low-carb vegan and vegetarian diet groups, respectively.
HbA1c, meanwhile, fell by 0.99% (95% CI, -1.07 to -0.9) in the low-carb vegan diet group and by 0.88% (CI at 95%, -0.97 to -0.8%) in the vegetarian diet group.
In terms of the environmental impact of each diet, potential greenhouse gas emissions were significantly lower with the low-carb vegan diet compared to the vegetarian diet (0.63 kg CO2; 95% CI, -0.99 to -0.27), according to the researchers.
They reported that changes in emission rates correlated with changes in risk factors, such as:
- LDL cholesterol (r = 0.25);
- systolic blood pressure (r = 0.25); and
- diastolic blood pressure (r = 0.23).
“We believe that the relationship between greenhouse gas emissions, LDL cholesterol, and blood pressure in this trial supports the increased use of plant-based diets for human and environmental health,” Jenkins and these partner’work.
Limitations of the study that the researchers acknowledged include the general health of the participants and its short duration of 3 months. It was also unclear whether full life-cycle analyzes had been carried out for greenhouse gas emission rates.
Jenkins and colleagues concluded that although non-inferiority has not been established, the low-carb vegan diet appears to be suitable as a weight-loss diet in people with type 2 diabetes.