This Is Your Brain on Carbs — Decades After You Eat Them

Carb Up: with the right kind, that is, if you want to support long-term brain health. While science has historically analyzed carbohydrate intake for short-term health outcomes, like weight, body composition, and blood sugar stability, new research suggests that the quality of carbs we eat affects how our brains age, a decade and more down the road. 

The Study: Researchers analyzed data from more than 200,000 dementia-free adults in the UK Biobank and followed them for roughly 13 years. Using detailed dietary questionnaires, they estimated each person’s glycemic index (how fast carbs raise blood sugar) and glycemic load (both the quality and amount of carbs). People whose diets skewed toward higher-glycemic foods were more likely to develop dementia. Those who ate lower- to moderate-GI diets had a lower risk.

The Takeaway: This should come as no surprise, but whole-food sources of carbohydrates, like fruits and fibrous grains, improve health while ultra-refined sources do not. Emphasizing whole grains, legumes, vegetables, and other lower-GI foods may be a small but meaningful way to support long-term brain health.

Keep in Mind: This was an observational study, meaning it can’t prove cause and effect. Diet was self-reported, and many lifestyle factors influence dementia risk.