A research-rating system has identified gaps in studies that assess the connection between diet and various health risks.

In this 2018 trial, participants lost 12% bodyweight through caloric restriction, and were then given a high, medium, or low carb diet. Those on the high and medium carb diets had to maintain a much more calorically restricted diet in order to maintain their body weight.

Part 2 of this series explores how a focus on food policy could tackle the obesity crisis.