Department of Psychology,Lancaster University,Lancaster,UK.
Department of Psychology,University of Central Lancashire,Preston,Lancashire,UK.
Proc Nutr Soc. 2017 Nov;76(4):466-477. doi: 10.1017/S0029665117000829. Epub 2017 Jun 27.
The brain has a high metabolic rate and its metabolism is almost entirely restricted to oxidative utilisation of glucose. These factors emphasise the extreme dependence of neural tissue on a stable and adequate supply of glucose. Whereas initially it was thought that only glucose deprivation (i.e. under hypoglycaemic conditions) can affect brain function, it has become apparent that low-level fluctuations in central availability can affect neural and consequently, cognitive performance. In the present paper the impact of diet-based glycaemic response and glucose regulation on cognitive processes across the lifespan will be reviewed. The data suggest that although an acute rise in blood glucose levels has some short-term improvements of cognitive function, a more stable blood glucose profile, which avoids greater peaks and troughs in circulating glucose is associated with better cognitive function and a lower risk of cognitive impairments in the longer term. Therefore, a habitual diet that secures optimal glucose delivery to the brain in the fed and fasting states should be most advantageous for the maintenance of cognitive function. Although the evidence to date is promising, it is insufficient to allow firm and evidence-based nutritional recommendations. The rise in obesity, diabetes and metabolic syndrome in recent years highlights the need for targeted dietary and lifestyle strategies to promote healthy lifestyle and brain function across the lifespan and for future generations. Consequently, there is an urgent need for hypothesis-driven, randomised controlled trials that evaluate the role of different glycaemic manipulations on cognition.
大脑的代谢率很高，其代谢几乎完全局限于葡萄糖的氧化利用。这些因素强调了神经组织对稳定和充足的葡萄糖供应的极度依赖。尽管最初人们认为只有葡萄糖缺乏（即低血糖状态）才能影响大脑功能，但现在已经很明显，中枢葡萄糖供应的低水平波动会影响神经，进而影响认知表现。在本文中，将回顾基于饮食的血糖反应和葡萄糖调节对整个生命周期认知过程的影响。数据表明，尽管急性血糖升高会在短期内改善认知功能，但更稳定的血糖水平，避免血糖循环中更大的峰值和低谷，与更好的认知功能和降低长期认知障碍的风险相关。因此，一种能确保在进食和禁食状态下为大脑提供最佳葡萄糖供应的习惯性饮食，对于维持认知功能最为有利。尽管目前的证据很有希望，但还不足以提供明确的基于证据的营养建议。近年来肥胖、糖尿病和代谢综合征的发病率上升，凸显了需要针对饮食和生活方式采取策略，以促进整个生命周期和后代的健康生活方式和大脑功能。因此，迫切需要进行假设驱动的、随机对照试验，以评估不同的血糖控制对认知的作用。
