每天要面對來自生活、工作的壓力對於很多現代人來說已是家常便飯，但隨之而來的是由壓力引起的健康隱患，包括睡眠不足和心臟疾病等。你知道嗎，除此之外，壓力還可以使人的體重增加，甚至導致肥胖？本期選文討論壓力可能讓人變胖的原因。
課文內容Vocabulary: nutrition and health 詞彙：營養和健康
Have you ever had a stressful day? Many people do in the course of their daily lives. And on these high-pressure days, they might find themselves reaching for a sugary snack. Perhaps this is part of their daily routine. Or perhaps on this particular day, their self-control is a bit low and they feel compelled to take a sugar hit.
Stress is natural. That feeling of strain or pressure is a biological response, and under the right circumstances can be a great source of motivation. However, too much stress, especially chronic stress, has been linked to sleep disruption, a higher likelihood of a stroke, heart-attack, ulcer or depression, among other things. But why should stress make a person comfort eat?
Dr Giles Yeo, a member of the BBC’s Trust Me, I’m a Doctor team, got together with scientists from Leeds University to conduct an experiment into the effect of stress on blood sugar. Dr Yeo was subjected to a stress test. In the first stage, he was forced to answer mathematical questions rapidly. In the second, he had to immerse his hand in a bath of ice-cold water for a period of time.
Before and after these tests, the Leeds scientists would measure Dr Yeo’s blood sugar levels. These are the levels which rise when we eat as our body takes in the energy of the food. In a healthy person, these levels quickly return to normal. However, when Dr Yeo was being deliberately subjected to stress, his blood sugar took six times longer to drop than on a stress-free day.
When we become stressed, our bodies enter 『fight or flight』 mode. Because our body believes it’s under attack, it releases glucose into the blood to provide energy for muscles. However, if we don’t use that energy, our body then releases insulin to make the blood sugar levels drop. This drop causes a hunger response: you want to eat. And what you particularly crave is sugary food, which rapidly replenishes the energy you have lost. If this happens repeatedly, over a long enough period, these high-calorie foods can lead to obesity.
So what can we do to combat the stress? In an article for the BBC, Dr Michael Mosley recommends 『stress-busting』 techniques, like exercise, gardening, mindfulness or another activities that you enjoy. But his strongest recommendation is trying to get a good night’s sleep. A recent study carried out by researchers at King's College, London found that if you deprived people of sleep, they would consume, on average, an extra 385kcal per day, which is equivalent to the calories in a large muffin. So, try sleeping to decrease stress, and as a result make it easier to keep yourself a little trimmer.