Cutting calories may improve memory among healthy elderly men and women, a new study from Germany hints. In the study, researchers found that people who cut their calorie intake by approximately 30 percent performed better on standard memory tests after just three months.
"Our study may help to generate novel prevention strategies to maintain cognitive functions into old age," Dr. A. Veronica Witte and colleagues from University of Munster wrote in the latest issue of Proceedings of the National Academy of Sciences.

Animal studies have shown that diets low in calories and rich in unsaturated fatty acids - the kind found in olive oil and fish - are beneficial for brain function, helping to improve memory in aging rats.

To see whether the same effects can be induced in humans, Witte's team divided 50 normal- to overweight individuals whose average age was 60 years into three groups. One group restricted by up to 30 percent the amount of calories they consumed; a second group increased their consumption of unsaturated fatty acids by up to 20 percent; and a third group, serving as the control group, made no changes.

According to the investigators, the calorie-restricted group saw a significant 20 percent average increase in verbal memory scores after 3 months. In contrast, no significant changes in memory performance emerged in the two other groups.

The investigators also noticed that memory improvements in the calorie-restricted group correlated with decreases in insulin levels and "biomarkers" of inflammation in the body, and that these changes were most pronounced in those individuals who stuck closest to the prescribed calorie-restricted diet.

"To our knowledge, the current results provide the first experimental evidence in humans that caloric restriction improves memory in the elderly," Witte and colleagues note.

The results of this study, they add, "may help to develop new prevention and treatment strategies for maintaining cognitive health into old age."

德国的一项新研究表明，削减卡路里可以改善健康老年男女的记忆力.研究人员在研究中发现,那些减少卡路里摄入约30%的人,仅仅3个月后, 在标准记忆力测试中的表现就要好得多.

“我们的研究有助于形成新颖的预防策略,来保持老年人的认知能力,” 蒙斯特大学的A.维罗妮卡.威特博士在最近一期的国家科学院学报中这样表述.

动物实验显示,低卡路里和富含不饱和脂肪酸的食物－－橄榄油和鱼中发现的那种－－对大脑的官能有利,有助于改善衰老的老鼠的记忆力

为了弄清楚在人类中是否会产生同样的效果,威特研究小组将50名平均年龄60岁、体格从正常到超重的研究对象分成了3组。第一组的卡路里摄入被控制在原有水平的30％，第二组不饱和脂肪酸的摄入量增加到原有水平的20％，第三组作为控制组，不作任何改变。

据研究人员说，3个月后，卡路里限制组单词记忆的分数有了一个显著的20％的平均增长。相反，其他两组表现出的记忆成绩没有显著的变化。

研究人员还注意到，卡路里限制组的记忆改善与体内胰岛素水平和炎症的生物标记物的降低是相关联的，并且这些变化在那些严格遵守指定的卡路里限制食谱的研究对象身上最为明显。

“就我们所知，目前的结果提供了卡路里限制可以改善老年人记忆力的第一个人类实验证据，”

这项研究成果，他们补充说：“有助于开发新的预防和治疗策略，以保持老年人的认知健康。”