Summer Remedies: Nightcaps and Sleep
We’re into the delicious season of mid-summer: ripe fruit, golden corn and lazy summer evenings. Looking around this issue of the Messenger will remind us that we’re also delighting in summer cocktails—so delicious when paired gracefully with fresh fruit or a balmy outdoor meal or concert. Ambrosia of the season!
Alcohol is certainly our most socially acceptable and widely consumed drug, a custom shared almost universally around the world. While each person’s preference of alcoholic beverage is unpredictable, we know a fair amount about what determines your tolerance for alcohol. The health of your liver affects your alcohol tolerance: anyone with liver damage—whether from alcohol, infection, or other disease—usually avoids alcohol because it’s too intoxicating and/or too nauseating! Popular wisdom suggests that drinking alcohol with a meal reduces the alcohol’s impact (true!) and that coffee is an antidote for drunkenness (false!)
Science meanwhile has pondered: how does alcohol both make you ready to party and ready to sleep? What researchers have discovered is that as you start drinking and your blood alcohol levels rise, so does norepinephrine—the neurotransmitter responsible for excitement, impulsivity, and pleasure-seeking! When you take a mineral water after your first drink, you lose that nice high, and can find yourself eagerly switching back to alcohol for the good feeling of a rising blood alcohol level. If you take a special picture of the brain during drinking, most folks show decreased activity in that part of the brain where we think rationally and make wise decisions. And the more alcohol, the less brain activity in the balance center of the brain.
Scientists have been all over the alcohol-affected brain, and have found over 100 places clearly identified as sensitive to alcohol. The biggest challenge has been finding the part of the brain involved when alcohol makes us sleepy. Current science suggests that once alcohol levels peak and start to fall, you start to feel sedated (sleepy, relaxed, it varies) because of alcohol’s stimulation of a sub-set of GABA receptors. GABA stands for gamma-aminobutyric acid, the dreamy neurotransmitter.
GABA receptors promote a feeling of relaxation and even sleepiness. They are the receptors targeted by Valium, popular sleep drugs such as Ambien, and evidently alcohol.
Alcohol, just like Valium and Ambien, can knock you out but it actually prevents you from sleeping. They literally “knock you out,” in that you may be unconscious but you are not truly asleep. In fact, alcohol will constantly wake you up during the night and prevent you from falling into deeper sleep stages.”
Losing an hour of the ideal sleep period (7-8 hours) impairs you as much as one alcoholic drink. Losing that hour for several days in a row prevents you from realizing you are impaired.
The neurotransmitter dance that helps us sleep each night involves a complex choreography in which cortisol (an adrenal hormone) and norepinephrine decline while melatonin and GABA (both in the brain) rise. Each substance has many different actions and touches a variety of brain receptors. Sleep drugs, and alcohol, are such poor mimickers of nature that they rely on the over-activation of a limited number of receptors. Under the influence of drugs or alcohol, your brain does not cycle through sleep stages, which is why I say you are unconscious, not asleep. (If you take something “physiological” to sleep, such as melatonin or GABA, you are much more likely to have normal sleep cycles.)
The takeaway from this info might be to switch to mineral water a couple hours before you know you’re hitting the pillow: give your body time to normalize so that you can have a good night’s sleep that is both restful and refreshing. After all, it’s summer and you have a big day to enjoy tomorrow!
Read more of Dr. Deborah’s healthy insights at www.DrDeborahMD.com.