Does Sugar Keep You Up at Night?

In a recent article about Chamomile tea and sleep, I received an interesting comment about sugar. In response to my claim that decaf tea could still keep you up if it’s full of sugar, commenter Jeremy said that sugar doesn’t keep you up at all.

Jeremy is right. I fell victim to one of the most persistent and pervasive myths that surround both food and sleep: that sugar gives you energy, makes you hyper, or keeps you up.

Not true. Sugar adds calories to your tea, but does not have a significant effect on energy levels or sleep.

In fact, sugar might even help sleep, rather than hinder.

From Your Spoon to Your Blood

Let’s start at the beginning. Sugar, be it white, brown, cane, beet, or even another sweetener like honey, is digested and turned into glucose in the bloodstream.

Glucose is indeed the energy molecule – and it’s available in an easily accessible form in sugar. But glucose does not correspond with long-term energy and wakefulness. Potato, rice, or bread is also converted to glucose in the blood – and there’s hardly a big concern that a baked potato will keep you up at night.

These starchy foods might even have an even more pronounced effect on blood glucose levels than sugar itself.  There is no unique chemical properties of sugar that make it special with regards to wakefulness and sleep, compared to any other source of glucose.

Sugar Science Trumps Sugar Myth

Perhaps the most common misunderstanding has to do with kids and sugar. Many parents, and those exposed to their rampaging children, blame sugar for hyperactivity.

Nope. For at least 30 years, researchers have known that sugar does not cause a hyperactive spike in energy in children. Double-blind tests are conclusive – if the kids are hyper, the reason isn’t sugar. The cause can vary, but it’s most likely a combination of confirmation bias, and the fact that the times that kids get sugary treats (birthdays, Christmas, holidays) are already cranking the kids up to max.

Don’t think that sugar affects you any differently just because you’re not a hyper kid, either. One study compared light physical activity vs sugar consumption to see which was more stimulating. A brisk walk wins every time. The sugar-eaters reported a slight initial boost in energy levels. However, this was followed shortly by a significant crash and an increase in sleepiness.

These results are repeated in an experiment comparing sugary drinks, aspartame-sweetened drinks, and plain water. The sippers that had sugar in their drink reported sleepiness half-an-hour after consumption – not alertness.

So here we are – sugar does not wake you up and won’t keep you up. But that’s only half the story.

Can Sugar Help You Sleep?

In previous articles, we’ve looked at a few chemicals to do with sleep, primarily adenosine and how it relates to coffee and sleep. But, with the human body being the complex interplay of hormones and glands that it is, there’s more than just one chemical that works to regulate sleep.

Orexin, also known as hypocretin, is a neurotransmitter produced in the brain. It works to regulate arousal, wakefulness, and appetite.  Orexin is a key factor in sleep and wakefulness. To drive home the importance of orexin, sufferers of the most common form of narcolepsy are missing just this hormone.

The relationship between orexin and sleep basically breaks down to this:

• High orexin: Wakefulness
• Low orexin: Sleepiness

And that’s where sugar comes in. Studies indicate that large amounts of glucose in the bloodstream are enough to suppress the activity of orexin neurons in the brain. And we know that consuming sugar is a sure way to dump glucose into your bloodstream. With the orexin activity slowed or stopped thanks to sugar, sleepiness follows.

Sweet Dreams

I had warned in a previous article that your evening decaf tea shouldn’t have any sugar in it. This was not true.

If you want to add a spoon of sugar to your chamomile, go for it. It may be that the sugar actually helps you fall asleep faster than otherwise.

But this means that the same is true in the morning. If you have a hard time getting going after breakfast, you may want to cut out your sugary drinks, cereals, and other sweet snacks. It may seem counter-intuitive, thanks to the ingrained sugar myth. But sugar is not a stimulant food – it is a sleepy food.

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