The Effects of Added Sugar Intake on Cerebrovascular Health in Midlife Adults

Introduction: A high-added sugar (HS) diet is detrimental to cardiometabolic health; however, less is known about the effects on cerebrovascular health. This study investigated the effects of an HS diet on cerebrovascular health in midlife adults (50-64 years old). We hypothesize that an HS diet compared to a low-added sugar (LS) diet will negatively impact cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). Methods: Using a crossover design, cerebrovascular function was tested in 29 participants (9 males / 20 females) after consuming a 10-day controlled HS (25% total energy) and LS (5% total energy) diet. CVR was quantified as the increase in CBF from rest in response to hypercapnia and normalized for the change in end-tidal carbon dioxide (CO2). Results: Resting CBF was similar between the two diets (HS: 54.4 ± 13.4; LS: 52.2 ± 13.0 ml/100g/min; p = 0.3), but the increase in CBF during hypercapnia was significantly lower during the HS diet (HS: +16.8 ± 10.2; LS: +22.9 ± 8.7 ml/100g/min; p = 0.01). This resulted in CVR being negatively impacted after consuming an HS diet compared to an LS diet (HS: 4.04 ± 2.5; LS: 6.08 ± 3.8 %; p = 0.01). Conclusion: A short-term (10-day) HS diet did not alter resting CBF, however, it did impair the cerebral blood vessels' ability to respond to stimuli in midlife adults. This study highlights the negative influence of an HS diet on cerebrovascular health, thus providing additional insight into a potential mechanism that may link an HS diet with poor brain health outcomes. NIH Grant P20 GM11325 This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.