Diets rich in high-glycemic foods such as white bread and potatoes are linked to a higher risk of dementia, found a recent study published in the International Journal of Epidemiology. The findings shed light on how long-term eating patterns can affect brain health later in life.
"These results indicate that following a diet rich in low-glycemic-index foods, such as fruit, legumes or whole grains, could decrease the risk of cognitive decline, Alzheimer's and other types of dementia," said lead author Mònica Bulló, professor at the Department of Biochemistry and Biotechnology at Rovira i Virgili University, Spain, in a press release.
For the study, researchers analyzed data from over 202,000 participants from the UK Biobank who did not have dementia at baseline. Data included dietary questionnaires, which allowed the researchers to calculate participants’ glycemic index (GI) and glycemic load (GL) - that is, how much specific foods and portion sizes raise blood sugar levels. They were followed for an average of 13 years, during which time, close to 2,400 participants were diagnosed with dementia.
Ultimately, the researchers found that diets rich in lower-glycemic foods were associated with a lower dementia risk, whereas those with more higher glycemic foods were linked to a greater risk. Those whose diets fell into the low to moderate glycemic range were 16% less likely to develop Alzheimer's, whereas those whose diets fell into the higher glycemic range were 14% more likely to develop the condition.
GI values between 1 and 55 are considered ‘low’, whereas those 56- 69 are considered ‘medium’ and those 70 - 100 are considered ‘high’. After adjusting for potential confounders, the researchers found that GI values under 49.3 were inversely linked to dementia risk.
Diets with a low glycemic index ‘may offer protective effects’ against all-cause dementia, Alzheimer’s disease, and vascular dementia, while diets with a high glycemic load may increase risk, wrote the researchers in their study.
“These findings underscore the importance of considering both carbohydrate quality and quantity in dementia prevention and management strategies,” they concluded.
Sources: Science Daily, International Journal of Epidemiology, Mayo Clinic
