Dietary carbohydrates: role of quality and quantity in chronic disease

  • Would reduction in total carbohydrate intake (currently typically 45-65% of total energy) help control body weight in general population and susceptible subgroups?

  • What is the role of a low carbohydrate diet in prevention and treatment of metabolic syndrome and type 2 diabetes, and in management of type 1 diabetes?

  • Does ketosis induced by severe carbohydrate restriction provide any unique metabolic benefits and, if so, in what clinical settings would this diet be advisable?

  • To what level should added (or free) sugars be restricted for optimum individual health and for the population as a whole?

  • Would substitution of fructose in added sugars with glucose based sweeteners provide metabolic benefit or harm?

  • Would substitution of free sugars with poorly digestible sugars, sugar alcohols, or artificial sweeteners provide health benefits or harms (eg, unexpected effects on the microbiome)?

  • Would increased intake of resistant starch provide health benefits?

  • What are the health effects of substituting whole grains with other high carbohydrate (fruits, legumes) or high fat (nuts, seeds, avocado) whole plant foods?

  • What are the long term effects of different types of carbohydrates on population risk of cancer, neurodegenerative diseases, and cognitive function?

  • Which carbohydrate based foods will provide an optimal combination of health benefits, environmental sustainability, cost, and public acceptability?

Human populations have thrived on diets with widely varying carbohydrate content.  Carbohydrate quality has a major influence on risk for numerous chronic diseases.  Replacing processed carbohydrates with unprocessed carbohydrates or healthy fats would greatly benefit public health.

The benefit of replacing fructose containing sugars with other processed carbohydrates is unclear. People with severe insulin resistance or diabetes may benefit from reduction of total carbohydrate intake.

For full text: The BMJ: Dietary carbohydrates: role of quality and quantity in chronic disease