van Zuuren EJ, et al. - In this systematic review, researchers compared the impacts of dietary carbohydrate restriction (≤ 40% of energy [%]) vs fat restriction (≤ 30%) over a period of ≥ 4 week on markers of metabolic syndrome and quality of life in people with type 2 diabetes (T2D), by analyzing 33 randomized controlled trials and 3 controlled clinical trials (n=2,161). Using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach, they evaluated the certainty of evidence. They used a random-effects model to calculate pool mean differences and 95% CIs. Low- to moderate-certainty evidence demonstrated that dietary carbohydrate restriction to a maximum of 40% vs dietary fat restriction to a maximum of 30% resulted in a slightly better metabolic control of uncertain clinical importance in people with T2D.