Kien C Lawrence, Dumas Julie A
Department of Pediatrics, Larner College of Medicine, University of Vermont, Burlington, VT 05402, USA.
Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, VT 05402, USA.
Nutrients. 2025 May 31;17(11):1897. doi: 10.3390/nu17111897.
Palmitic acid (PA) and oleic acid (OA) are, respectively, the most prevalent saturated and monounsaturated fatty acids (SFAs, MUFAs) in the human diet. The objective of this brief review is to explore how this ratio affects brain function. In two double-masked crossover trials in young adults, physical activity was greater and systemic inflammatory tone was diminished under a diet with a lower dietary PA/OA ratio compared to that of the typical North American Diet, and anger and total mood disturbance were diminished under the low- compared to the higher-PA/OA diet. In another diet trial in young women, functional magnetic resonance imaging showed that lowering the dietary PA/OA ratio decreased brain activation in regions of the basal ganglia, suggesting that brain function was reversibly altered by the dietary PA/OA ratio. Recently, a crossover trial in older adults showed that a lower dietary PA/OA ratio decreased systemic inflammatory tone and caused the greater activation of a working memory network. As people age, there are declines in cognition that impact functional abilities and independence, but the preservation of structural aspects of the brain in normal aging implies that there is the possibility of slowing, stopping, or reversing cognitive changes that impact daily life. Reducing pro-inflammatory cytokine secretion by lowering habitual PA intake for even brief periods of time may be one modality to improve cognitive function in older adults, not only in those with typical cognitive aging but in those with dementia as well.
棕榈酸（PA）和油酸（OA）分别是人类饮食中最常见的饱和脂肪酸和单不饱和脂肪酸（SFA、MUFA）。本简要综述的目的是探讨这一比例如何影响脑功能。在两项针对年轻人的双盲交叉试验中，与典型的北美饮食相比，饮食中PA/OA比例较低时，身体活动量更大，全身炎症水平降低，且与PA/OA比例较高的饮食相比，低PA/OA饮食时愤怒情绪和总体情绪困扰减少。在另一项针对年轻女性的饮食试验中，功能磁共振成像显示，降低饮食中PA/OA比例会降低基底神经节区域的脑激活，这表明饮食中的PA/OA比例可使脑功能发生可逆性改变。最近，一项针对老年人的交叉试验表明，较低的饮食PA/OA比例可降低全身炎症水平，并使工作记忆网络的激活增强。随着人们年龄的增长，认知能力会下降，这会影响功能能力和独立性，但在正常衰老过程中大脑结构方面的保留意味着有可能减缓、阻止或逆转影响日常生活的认知变化。即使在短时间内通过降低习惯性PA摄入量来减少促炎细胞因子的分泌，可能是改善老年人认知功能的一种方式，不仅适用于典型认知衰老的老年人，也适用于患有痴呆症的老年人。
