*3.2. Carbohydrates*

The majority (*n* = 3) of the identified carbohydrate nutritional intervention studies investigated the effect of high glycemic index (GI) carbohydrate consumption pre-sleep. Overall, high GI carbohydrate consumption resulted in increases in TST (7.9–62.4 min) and SE (0.4–8.1%), and consistent reductions in SOL (5.6–18.9 min). Afaghi and colleagues [26] also investigated the effect of a very low carbohydrate diet on sleep, showing an increase in TST (22.7 min) and SE (3.3%), and reduced SOL (5.6 min).
