What happens when somebody has a glass, we always hear a glass or two of wine in the evening or a cocktail after dinner or before dinner, how does that impact their sleep? And then we'll be sure to circle back in terms of what is reasonable ranges of behavior when it comes to avoiding alcohol or if it's age appropriate, et cetera.

- Enjoying alcohol. - Yeah. So alcohol, if we're thinking about classes of drugs, they're in a class of drugs that we call the sedatives. And I think one of the first problems that people often mistake, alcohol is often used as a sleep aid for people who are struggling with sleep when things like over-the-counter remedies, et cetera, or herbal remedies have just not worked out for them.

And alcohol, unfortunately, is anything but a sleep aid. The first reason that most people use it is to try and help them fall asleep. - And this process of this event that we call falling asleep, I have to imagine is a process. - It is a process. - Like everything in biology.

And that that process involves in some way, as we talked about push-pull before, turning off thinking, planning, et cetera, and turning on some sort of relaxation mechanism. I have to imagine that these two things are knobs turning in opposite directions that gives us this outcome we call falling asleep.

Alcohol, it seems, is helpful for some people to turn off their thoughts or their planning. Is that right? - Yes, it is. And so I think if we look at the pattern of brain activity, if I were to place you inside an MRI scanner where we're looking at the activity of your brain and watch you drifting off, some parts of your brain will become less active, other parts will become more active.

And this is the push-pull model. It's inhibition, excitation. But alcohol is quite different in that regard. Alcohol is, because it's a sedative, what it's really doing is trying to essentially knock out your cortex. It's sedating your cortex. And sedation is not sleep. But when we have a couple of drinks in the evening, when we have a couple of nightcaps, we mistake sedation for sleep, saying, well, I always, when I have a couple of whiskeys or a couple of cocktails, it always helps me fall asleep faster.

In truth, what's happening is that you're losing consciousness quicker, but you're not necessarily falling naturalistically asleep any quicker. So that's one of the first sort of things just to keep in mind. The second thing with alcohol is that it fragments your sleep. And we spoke about the quality of your sleep being just as important as the quantity.

And alcohol, through a variety of mechanisms, some of which are activation of that autonomic nervous system, that fight or flight branch of the nervous system, alcohol will actually have you waking up many more times throughout the night. So your sleep is far less continuous. Now, some of those awakenings will be of conscious recollection the next day.

You'll just remember waking up. Many of them won't be. And so, but yet your sleep will be littered with these sort of punctured awakenings throughout the night. And again, when you wake up the next morning, you don't feel restored by your sleep. Fragmented sleep or non-continuous sleep in this alcohol-induced way is usually not good quality sleep that you feel great on the next day.

The third part of alcohol in terms of an equation is that it's quite potent at blocking your REM sleep, your rapid eye movement sleep. And REM sleep is critical for a variety of cognitive functions, some aspects of learning and memory. It seems to be critical for aspects of emotional and mental health.

- You've described it before as a sort of self-generated therapy that occurs while we sleep. - Yeah, it's overnight therapy. You know, it's emotional first aid. - Certainly people that don't get enough sleep are very easy to derail emotionally. Not that one would wanna do that to people, but we all sort of fall apart emotionally.

I always think of it as almost like our skin sensitivity can be heightened when we are sleep deprived. Our emotional sensitivity is such that when we're sleep deprived, such that it takes a much finer grain of sandpaper to create that kind of friction. Things bother us. - Threshold to trigger.

- Even online comments bother us when we're sleep deprived. And never when we're well-rested. - I would love to say that I never look at them except I look at maybe every one of them. - Here I will editorialize because the notion of not looking at comments is unreasonable to ask of any academic.

Because academics, we are all trained to look at our teaching evaluations. And just like with online comments, to ignore 20% of them. No, I'm kidding. We look at them all in any event. So in terms of translating this to behavior, I don't particularly enjoy alcohol. I guess I might be fortunate in that sense, but I also have never really experienced the pleasure of drinking alcohol.

I sometimes like the taste of a drink, but I never liked the sensation. So that's, I don't have a lot of familiarity with this, but many people do. And I understand that. So let's say somebody enjoys a glass of wine or two with dinner and they eat dinner at 7 p.m.

Is that likely to disrupt their sleep at all? Let's just sort of, let's make this a series of gradations. - And the answer is yes. I think once they just looked at a single glass of wine in the evening with dinner, and I would be untruthful if I didn't just simply say it has an effect and we can measure that in terms of the actual- - Less REM sleep.

- Less REM sleep. And one of the fascinating studies, I can't remember what dose, I think they got them close to a standard illegal blood alcohol level. So maybe they were a little bit tipsy. And yes, you see all of the changes that we just described. They sort of lose consciousness more quickly.

They have fragmented sleep and they have a significant reduction in REM sleep. But what was also interesting because REM sleep, as we spoke about before, is a time when some hormonal systems are essentially recharged and refreshed, growth hormone being one of them. There was well over a 50%, five zero drop in their growth hormone release during alcohol-laced sleep at night.

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