Plain language summary
Cognitive impairment is a public health problem due to its increasing prevalence in the aging population. Despite pharmacological advances, there are not yet effective treatments to delay or reverse cognitive impairment. Moreover, there is limited knowledge of Alzheimer disease modifiable risk factors namely nutrition. The aim of this review was to grade, classify and provide recommendations for the preferred diet to prevent or to treat cognitive impairment. This review shows that: - some nutritional factors appear to either increase the risk of cognitive decline or protect against it. - risk could be conferred by diets high in milk and dairy products whereas some protection can be offered by adhering to a Mediterranean diet to decrease the risk of cognitive decline. - it is important to follow a diet rich in mono- and poly- unsaturated fatty acids, fruit and vegetable, vitamin D and low in saturated fatty acids. Authors conclude that diet is an important modifiable factor to prevent or protect against cognitive decline.
Abstract
Aging is associated with cognitive declines leading to mild cognitive impairments or Alzheimer disease. Nutrition appear to protect from aging. Some dietary factors could either increase or protect against cognitive declines. This article aimed to provide GRADE recommendations related to nutrition aspects able to prevent or to treat cognitive impairments. A comprehensive literature review was performed using Medline database. The GRADE approach was used to classify quality of the existing evidence (systematic review or meta-analysis).The GRADE process led us to formulate seven key nutritional recommendations to manage cognitive declines, but did not allow us to do it for protein, vitamin B or antioxidants. Thus, 1) adherence to a Mediterranean diet (GRADE 1B); 2) high-level of consumption of mono- or poly- unsaturated fatty acids combined to a low consumption of saturated fatty acids (GRADE 1B); 3) high consumption of fruits and vegetables (GRADE 1B); 4) higher vitamin D intake (GRADE 1C) than the recommended daily allowance. In addition, a ketogenic diet, a low consumption of whole-fat dairy products or a caloric restriction are promising nutritional habits although the evidence does not yet support widespread uptake (GRADE 2C). In conclusion, nutrition is an important modifiable factor to prevent or protect against cognitive decline. Nevertheless, more studies are required to determine specific guidelines such as duration and amounts of nutrients to help older adult to maintain a healthy cognitive life.
Methodological quality
Jadad score
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Not applicable
Allocation concealment
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Not applicable
