Can eating a specific food or following a particular diet help prevent or delay dementia caused by Alzheimer’s disease? Many studies suggest that the choices we make in what we eat affects the aging brain’s ability to think and remember. These findings have led to research on general eating patterns and whether they might make a difference. Studies indicate that inflammatory foods can raise the risk of dementia.
A study looked at the diets of over 1000 people, mean age 71, for an average of 3 years. Dieticians categorized an inflammatory index score based on 3 levels of inflammation: low, intermediate and high inflammatory foods. It is no surprise that the high inflammatory diet category had three times the incidence of dementia than the low category group. Those in the low category diet ate more vegetables, fish and fiber. While those in the high inflammatory food group ate more red meat, processed meat, alcohol and sugar. Other research has shown that artificial sweeteners, such as aspartame, are associated with risk for stroke and dementia as well. So how does certain foods change our physiology and raise the risk of certain health conditions?
As humans age, the immune system gradually deteriorates, creating a pro-inflammatory state. This process actually starts even when we are younger but is noted more clearly as we age. This pro-inflammatory state increases the risk of chronic disease, has been associated with cognitive decline and implicated in the pathogenesis of dementia. This process is called immunosenescence. The inflammatory cytokines that promote inflammation reduce brain-derived neurotropic growth factor (BDNF) and create more oxidative stress, increasing the risks for cognitive impairment or dementia. Diet can modulate systemic inflammation.
Changes in the brain can occur years before the first symptoms of cognitive decline. These early brain changes suggest a possible window of opportunity to prevent or delay dementia symptoms. Risk factors for Alzheimer’s that we can’t change are age and genetics. Research has shown that people can control lifestyle choices such as diet, exercise and cognitive training which affects biological mechanisms, such as oxidative stress and inflammation, that underlie Alzheimer’s.
Some other things to consider: perhaps diet works indirectly by affecting other risk factors for Alzheimer’s disease such as obesity, diabetes and heart disease. Secondly, more and more research is focusing on the relationship between our microbiome (microbes or small organisms that live in the digestive tract) and age related conditions that lead to Alzheimer’s.
One diet that continues to to show promise and gets very little criticism is the Mediterranean Diet. This meal plan emphasizes fruits, vegetables, whole grains, legumes, fish and other seafood and healthy fats such as olive oils, nuts and seeds. It has very low amounts of red meat, eggs and sugars. A variation of this would also incorporate the DASH Diet (Dietary Approaches to Stop Hypertension) which can also help lower blood pressure, reduce cardiovascular disease and dementia. Check out the Mind diet to help you get started.
References:
- Pase MP, Himali JJ, Beiser AS, et al. Sugar- and Artificially Sweetened Beverages and the Risks of Incident Stroke and Dementia: A Prospective Cohort Study. Stroke. 2017;48(5):1139-1146. https://www.ahajournals.org/doi/10.1161/STROKEAHA.116.016027
- https://www.practiceupdate.com/content/artificially-sweetened-beverages-strokeand-dementia/52314/62
- https://n.neurology.org/content/early/2021/11/10/WNL.0000000000012973