来源：《新科学家》
原文刊登日期：2023年5月31日
Eating a diet that is high in fat and sugar may reduce sleep quality by messing with the brain’s electrical activity during deep sleep.
高脂高糖饮食可能会扰乱深度睡眠时的大脑电波活动，从而降低睡眠质量。
When we go to sleep, our brain’s electrical activity slows down. The higher-frequency brainwaves that dominate while we are awake, called beta waves, are gradually replaced by lower-frequency ones called delta waves.
当我们入睡时，大脑的电波活动减慢。在我们清醒时占主导地位的高频脑电波，被称为β波，逐渐被低频的δ波所取代。
The deepest, most restorative stage of sleep – called slow-wave sleep – has the highest proportion of delta waves. It typically occurs in the first half of the night and allows the body to repair itself and consolidate memories.
在最深层、最能恢复体力的睡眠阶段——被称为慢波睡眠——δ波的比例最高。它通常发生在前半夜，使身体能够自我修复并巩固记忆。
Jonathan Cedernaes at Uppsala University in Sweden and his colleagues tested the effects of a Western-style high-fat, high-sugar diet on slow-wave sleep in 15 men with an average age of 23.
瑞典乌普萨拉大学的Cedernaes和他的同事测试了西式高脂肪、高糖饮食对15名平均年龄为23岁的男性慢波睡眠的影响。
The men were randomly assigned to eat a high-fat, high-sugar diet or a low-fat, low-sugar diet for one week. They then slept for one night in a laboratory wearing an electroencephalography (EEG) cap to record their brain’s electrical activity. After a break of several weeks, they switched to the other diet and repeated the laboratory sleep study.
这些男性被随机分配在一周内吃高脂肪、高糖饮食或低脂肪、低糖饮食。然后，他们戴着脑电图(EEG)帽在实验室里睡了一晚，以记录他们的脑电活动。休息几周后，他们改用另一种饮食，并重复实验室睡眠研究。
The participants were provided with all their meals and had to eat them at set times. The high-fat, high-sugar diet included foods like pizza and chocolate, whereas the low-fat, low-sugar diet contained foods like salmon and vegetables. The two diets were matched for calories.
研究人员为参与者提供了所有的食物，并且必须在规定的时间进食。高脂肪、高糖饮食包括披萨和巧克力等食物，而低脂肪、低糖饮食包括鲑鱼和蔬菜等食物。这两种饮食的卡路里含量相当。
Each man typically slept for the same length of time on the two diets and felt their sleep quality was the same. However, the EEG recordings showed that the high-fat, high-sugar diet disrupted slow-wave sleep by reducing the proportion of delta waves and increasing beta waves, suggesting it was less restful. This happened in 11 out of the 14 men for whom full results were collected.
在摄入这两种饮食后，每个人的睡眠时间通常没有变化，他们觉得自己的睡眠质量也是一样的。然而，脑电图记录显示，高脂肪、高糖的饮食会减少δ波的比例，增加β波的比例，从而扰乱慢波睡眠，这表明睡眠并不那么安静。在收集了完整结果的14名男性中，有11人出现了这种情况。
The effect may be because sugar and fat activate brain pathways that increase how awake people feel, but more work is needed to unravel the mechanisms, says Cedernaes. He also hopes to repeat the study to find out if the change also occurs in women.
Cedernaes说，这种影响可能是因为糖和脂肪激活了大脑通路，增加了人们清醒的感觉，但需要做更多的工作来解开其中的机制。他还希望重复这项研究，看看这种变化是否也发生在女性身上。
We don’t know the long-term impact of disrupting slow-wave sleep in this way, but we do know that poor diets typically lead to worse health, which may partly be explained by their effect on sleep quality, he says.
他说：“我们不知道以这种方式扰乱慢波睡眠的长期影响，但我们确实知道不良饮食通常会导致健康状况恶化，这在一定程度上可以用不良饮食对睡眠质量的影响来解释。”
The amount of slow-wave sleep that we get naturally declines with age, so eating a healthy diet may be particularly important in older age to protect against further losses in sleep quality, says Cedernaes.
Cedernaes说，随着年龄的增长，我们获得的慢波睡眠时间自然会减少，所以在老年人中，健康的饮食对于防止睡眠质量进一步下降尤为重要。