Wing R R, Vazquez J A, Ryan C M
Department of Psychiatry, University of Pittsburgh School of Medicine, PA, USA.
Int J Obes Relat Metab Disord. 1995 Nov;19(11):811-6.
To determine whether ketogenic weight reducing diets have adverse effects on cognitive performance.
21 overweight women (mean BMI = 41 kg/m2).
Randomized double-blinded study.
Subjects were randomized to ketogenic or nonketogenic liquid formula very low energy diets, that were comparable in energy and in protein content. Subjects remained on the diet for 28 days and were reevaluated periodically with brief measures of cognitive performance assessing attention and mental flexibility.
Weight losses were comparable on the two diets (Mean = 8.1 kg). Performance on attention tasks did not differ as a function of the diet. However, performance on the trail making task, a neuropsychological test that requires higher order mental processing and flexibility, was adversely affected by the ketogenic diet. The worsening in performance was observed primarily between baseline and week one of the ketogenic diet.
Further research is needed to confirm this finding and to determine whether ketogenic diets negatively affect other complex mental tasks, such as problem solving.
确定生酮减肥饮食是否对认知能力有不良影响。
21名超重女性（平均体重指数=41kg/m²）。
随机双盲研究。
受试者被随机分配到生酮或非生酮液体配方极低能量饮食组，两组饮食的能量和蛋白质含量相当。受试者坚持饮食28天，并通过评估注意力和心理灵活性的简短认知能力测试定期进行重新评估。
两种饮食的体重减轻情况相当（平均=8.1kg）。注意力任务的表现不因饮食而有所不同。然而，生酮饮食对连线测验任务（一种需要高阶心理加工和灵活性的神经心理学测试）的表现有不利影响。表现恶化主要出现在生酮饮食的基线期和第一周之间。
需要进一步研究来证实这一发现，并确定生酮饮食是否会对其他复杂的心理任务（如解决问题）产生负面影响。
