It may be second nature to reach for a sweet boost when tired in the evening but this could lead to a disturbed night. How do you kick the habit?
Sugar is bad; sugar is evil; sugar is the devil. We all know that, although that doesn’t stop us from heaping it over our Weetabix every morning and adding it to tea and coffee.
Too much sugar can lead to weight gain, causes tooth decay and increases the risk of diabetes. But it also has another profound effect – it messes with your sleep, and in such a way that your sleeplessness will leave you with a craving for more sugar.
A 2016 study found that people who have diets high in sugar tend to sleep less deeply and display greater restlessness at night. According to Dr Michael Breus – AKA “the sleep doctor” – a US clinical psychologist who specialises in sleep disorders, too much sugar leads to a tendency to eat later in the day because blood sugar levels are zigzagging out of control. That adversely affects sleep, and your disrupted sleep will, in turn, produce an even greater craving for sugar the next day. The vicious circle is complete.
Having too much sugar at night can be detrimental to our health. “When you eat sugar, your blood sugar levels rise and your pancreas releases insulin, which helps the sugar to be taken back into the cells, giving them fuel to run on,” says the dietitian Alex Evans. “Eating sugar late at night overstimulates you. It gives you energy and makes you ready for activity, but that is not what we’re trying to do at night. We’re designed to shut down towards the end of the day.”
“Sugar uses up a lot of magnesium, which you need for sleep,” says the nutritional therapist Charlotte Watts, author of Good Mood Food and The De-Stress Effect. She points out that you should, in particular, avoid late-night chocolate, which contains caffeine and other stimulants.
Dr Paul Kelley, a researcher into sleep patterns, accepts the link between high sugar intake and disturbed sleep, but cautions that more data is needed before we fully understand the causality. “Poor sleep and eating sugar and fatty foods do go together, but there is evidence on both sides about which direction it goes in,” he says. “Does eating sweet things make you sleep less or does sleeping less make you eat sweet things?”