Read a book, take a hot bath, maybe count sheep – we all have our own ways of trying to fall asleep. However, all too often these efforts prove unsuccessful.
Studies have found that around a third of people in the UK suffer from insomnia, which means they struggle to fall asleep or stay asleep, and around two million people are dependent on sleeping pills.
But a growing body of research suggests that there may be an easier way to improve your sleep, and that’s by improving what you eat.
While it has long been recognized that beverages and foods that contain caffeine, a stimulant, can make sleep difficult, it appears that certain food groups, such as fruits, vegetables, and even certain breads, can have the opposite effect.
A growing body of research suggests that there may be an easier way to improve your sleep, and that’s by improving what you eat.
This was the finding of a review of studies, published recently in the Annual Review of Nutrition.
Marie-Pierre St-Onge, associate professor of nutritional medicine at Columbia University in New York, one of the authors of the article, told Good Health: “We found that eating a diet that contains a lot of fruits and vegetables as well as legumes and dark whole grain breads, was associated with better quality of sleep. ‘
The review built on other findings, including a study published in Nutrients in 2020 involving 400 women, which found that the more they adhered to a Mediterranean-style diet rich in fruits, vegetables, nuts, and lean protein, the more they slept. . improved quality.
This study was self-reported, meaning the women themselves were writing down their diet and sleep, but other scientists have seen similar results.
In fact, following their own study, researchers at the University of Leeds, writing in the BMJ Open in 2018, were so convinced of the link between diet and sleep that they said it could have “important implications for lifestyle and sleep. behavior change policy “.
His research involved 1,612 adults who had to write down their sleep patterns plus their fruit and vegetable intake for four days. Those who slept less than seven hours a night consumed 24 g less of fruits and vegetables a day than those who slept between seven and eight hours.
This study was self-reported, meaning the women themselves were writing down their diet and sleep, but other scientists have seen similar results.
Also, while a healthy diet can benefit sleep, previous research by Dr. St-Onge and her team suggests that eating more saturated fat and sugar can disrupt sleep.
In a 2016 study, published in the Journal of Clinical Sleep Medicine, 26 volunteers underwent sleep polysomnography for five nights, with sophisticated monitoring equipment used to record brain waves and other vital signs that can determine sleep. quality and quantity of sleep.
This type of analysis can determine, for example, how long people spend in deep sleep and how often they wake up.
“The advantage of this study was that we had controlled their diet, so we knew exactly what they were eating,” says Dr. St-Onge. “So for the first four days they had a healthy diet, low in saturated fat and containing recommended levels of fiber and sodium. [salt]. On the fifth day, they were able to self-select what they were eating, and that’s when we saw that they had a much higher intake of saturated fat, salt, and sugar. “
When the team analyzed the group’s sleeping habits, they found some surprising differences.
“On the fifth day, it took them almost twice as long to fall asleep, 12 minutes longer, compared to the previous days,” Dr. St-Onge told Good Health. “They also spent less time in deep sleep, which is the most restorative stage of sleep.”
This is when brain waves slow down, allowing memories to be archived, and when the pituitary gland pumps out the growth hormone necessary to regenerate cells. The study found that the volunteers had 24 minutes of this deep sleep on the fifth night, compared to 29 minutes on the days when they had a better diet.
“That represents a 15 percent reduction, which is quite a bit,” says Dr. St-Onge.
From there, he went on to look at the specific foods they had eaten and their effects, and was able to identify three key food groups that had a significant impact.
“Volunteers who had eaten more fiber spent less time in light sleep and more time in deep sleep,” he says, “while eating more saturated fat was associated with less slow-wave sleep.” [deep] sleep.
And the more sugar they had, the more excitement they had that night. We believe that in the case of sugar, it leads to unstable blood sugar levels, which is what interrupts sleep. ”
It is not known why, although an earlier study published in PLoS ONE in 2015, involving 63 patients with type 2 diabetes, also found that poor blood sugar control was associated with poor sleep.
While sugar can be detrimental to sleep, there are “multiple components in plant-based foods that may be associated with better sleep,” says Dr. St-Onge.
Fiber is just one example. St-Onge’s research has found that those who eat the most fibrous legumes, which include legumes like lentils and chickpeas, have the best ‘sleep efficiency’ (in other words, the amount of time they spend in bed when they are actually asleep).
St-Onge’s research has found that those who eat the most fibrous legumes, which include legumes like lentils and chickpeas, have the best ‘sleep efficiency’ (in other words, the amount of time they spend in bed when they are actually asleep)
And when it comes to the Mediterranean-style diet in general, Dr. St-Onge suggests that its sleep benefits are derived from tryptophan, an amino acid that the body uses (although it cannot produce itself) to make the hormone melatonin. , which helps make us sleepy, and serotonin, which stabilizes the mood and also plays a role in sleep.
However, to be effective, tryptophan (found, for example, in turkey, fish, bananas, and seeds) has to cross the blood-brain barrier, the semi-permeable wall of cells that protects the brain from toxins. .
In order to cross it, tryptophan has to, in effect, get on a ‘carrier’ protein, but it can be pushed out of the way by other amino acids waiting to cross. And at least one study has concluded that “this limits the amount of serotonin that can be produced.”
“In the case of melatonin, your body is really good at making it,” says Kevin Morgan, emeritus professor of psychology at Loughborough University, who has spent much of his career researching sleep.
‘Sit in a bright light in the morning and you will start the production of everything you need.’
Catherine Collins, a Surrey-based NHS dietitian, believes that there is not yet enough evidence to recommend a single diet, or foods, as a way to improve sleep.
“The Mediterranean diet is the gold standard of diets, there is no question about that,” he says. “However, the studies to date have not involved enough people or conducted long enough to say with certainty that the specific components help sleep.”
But, he says, the fact that the diet has anti-inflammatory effects “means that it may be beneficial to health in other ways, such as for people with arthritis, for example, and may indirectly benefit long-term sleep.”
And the fact that it makes you feel full for longer can also be beneficial, he adds.
“Going to bed hungry won’t help you sleep, but the Mediterranean diet is quite high in healthy fats, which gives it a low glycemic index and makes you feel fuller for longer.”
Professor Morgan believes that the key is not what you eat, but when you eat.
“Mealtime is very valuable: it is the metronome of your circadian rhythm, which, as the name suggests, is the rhythm that makes your biological clock tick,” he says.
‘The guardian of good sleep is regularity. If you can maintain a boring lifestyle (eating and going to bed at the same time every day), it will encourage good sleep. But in my opinion, you can’t fix interrupted sleep by changing what you eat. ‘
Dr. St-Onge, however, believes her research is promising. ‘If we can find ways to improve the health of the population in a simple way, I think it is worth trying.
As for your own dream? “I already have a healthy diet,” he says. ‘But when I wake up thinking’ That was an exceptionally good dream ‘, I try to remember what I did that might have helped with that.
“We often pay our attention to bad sleep, but it can help to take a more positive approach.”
.
