Dietary patterns and delay in onset of Alzheimer’s Disease

[摘要] 1.1Dietary PatternsLevels of evidence of dietary patterns and their role in the delay in the onset of Alzheimer’s Disease (AD). •Population studies which examined cohorts from several countries including the USA, the Netherlands, Finland and Italy suggest that adherence to diets based on health policy guidelines may be associated with improved cognitive function•Three recent reviews have concluded that while studies to date provide moderately compelling evidence that adherence to the Mediterranean Diet is associated with a reduced risk of AD, further confirmation in other study populations with different ethnicities and different dietary habits is warranted. •There are currently no studies linking the vegetarian, Palaeolithic, Okinawa, ketogenic or caloric restriction diets to the prevention of cognitive decline or Alzheimer’s disease.1.2Dietary componentsA review of a range of dietary components that have been associated with improvements in cognition in the ‘popular press’ has identified that many of the studies cited have been animal or in vitro studies of short duration, and therefore were outside the scope of this review. Many of the studies evaluating dietary components have been part of larger population studies and evaluations were based on food frequency questionnaire data, which can be affected by recall bias.Overall it was found:•There is inadequate evidence to assess the association between fruit and vegetable consumption on the delay of onset of AD and a low level of evidence for the consumption of vegetables and a decreased risk for cognitive decline. Further recent studies have found that a plant-food rich diet is associated with improved performance in several cognitive abilities in a dose-dependent manner. •For alcohol consumption, all drinkers had a lower risk of AD compared to non-drinkers and light to moderate alcohol use was protective for AD in both males and females.•There is inadequate evidence for a role of carbohydrate intake in AD. •There is preliminary evidence for an association between increased saturated fat intake and trans fat intake and risk of AD or cognitive decline.Higher n-3 polyunsaturated fatty acids (PUFA ), such as from oily fish, intake may be associated with better episodic memory over time, while higher monounsaturated fatty acids (MUFA) such as from olive oil, intake may be related to less cognitive decline. •There is inadequate evidence to assess the association of consumption of berries and berry flavanoids with cognition, however, flavanoid containing foods and beverages such as wine, tea and chocolate showed overall better cognitive performance in a dose dependent manner. •One prospective study reported a low intake of legumes was associated with the development of mild cognitive impairment. There were no human studies on consumption of nuts, seeds, grains and garlic and effects on cognition.The literature is beginning to reinforce the importance of studying dietary patterns rather than individual foods or nutrients due to likely synergistic effects of nutrient combinations. For example, a dietary pattern high in saturated fatty acids and also high in monounsaturated fatty acids may have opposing effects on AD risk and therefore result in an overall nil effect. Hence dietary patterns and food combinations may provide potential synergistic effects of nutrient combinations as dietary interventions for the delay of onset of AD.

[发布日期] 2011-06-28 [发布机构] CSIRO

[学科分类] 地球科学(综合)