Food and cognition
Diabetes type-2 and obesity are associated with increased risk of impaired cognitive functions, and cognitive decrease is considered as an additional feature of the metabolic syndrome. In fact, also in healthy individuals, i.e. in subjects with risk markers still within the normal range, there are relations between cardiometabolic risk markers and cognitive performance. Hyper-insulinemia as well as type-2 diabetes are risk factors for dementia, including also Alzheimer’s disease. An alarming more recent knowledge is the relation between childhood obesity and decreased cognitive functions. The underlying mechanisms are not fully understood but probably involve factors connected to insulin resistance and inflammation. The link between cardiometabolic risk and neuro-degeneration thus indicate a new target for prevention and therapy based on measures that reduce risk factors for the metabolic syndrome.
We have shown that it is possible to enhance cognitive performance by specific food concepts aiming at reducing cardiometabolic risk factors. A meal that induced a sustained net increment in blood glucose above the fasting value in the late postprandial period significantly improved cognitive performance in the postprandial period. The positive effects on cognitive functions in this respect are suggested to emanate from improved insulin sensitivity, possibly in combination with an enhanced neuronal energy supply. An additional finding was that we in healthy subjects revealed an inverse relationship between performance on cognitive tests and individual glucose tolerance.
We found that specific long chain omega-3 fatty acids from fish (DHA and EPA) improve cognitive performance in a 5 week intervention in health subjects. Previously it is known that omega-3 fatty acids have cardio-protective effects. The results in this project support such mechanisms; we found, both a decrease in cholesterol and blood pressure, i.e. improvements of important cardiometabolic risk markers. We observed an inverse relation between cognitive performance and cardiometabolic risk markers.
In another study a four week intervention with health subjects consuming of a whole diet combining several different metabolically beneficial food concepts improved both performance on cognitive tests, and important cardiometabolic risk markers, e.g. markers of inflammation and cholesterol, and reduced the predicted 10-years cardiometabolic risk (Framingham risk score). Cognitive performance was closely and inversely related to several risk markers and also strongly related to the predicted 10 years cardiometabolic risk.
The results obtained in the project are important and show that a relationship between metabolic risk factors and cognitive ability exists, not only in patients with metabolic disorders, but also in healthy subjects. This relationship highlights the importance of active preventive dietary measures. The positive message is that probably it is possible to reverse a negative trend with respect to cognitive function by dietary measures oriented to prevent cardiometabolic diseases. However, this research topic is still young and more research is needed to clarify the relationships between food/diet and cognition, and the links between cardiometabolic risk and cognitive decline. In this AFC project we will continue to evaluate cognitive effects and effects on mood of potentially “anti-diabetic” food concepts. The project can be expected to generate new knowledge in this respect, which is important when tailoring of new innovative foods with added health values. In addition, the project is expected to increase the knowledge concerning the connection between metabolism and cognitive function. Such data will be of paramount importance when designing preventive food concepts aiming at prevent neurodegenerative processes connected with metabolic disorders.
Project leader: PhD Anne Nilsson