Katie Breazeale, MS, RD, LD
It’s pretty common to feel relaxed and drowsy after that last cocktail or glass of wine at night, but does that alcohol really help you get enough high-quality sleep? What about alcohol and sports performance? Alcohol can affect you in multiple ways, let’s look at the different side effects of drinking.
Downside 1: It Dehydrates You
One of the main reasons for your throbbing skull and dry mouth the day after a big night on the town is dehydration. You lose much more water than you gain when you drink—even if you drink a lot. Ever notice how often you run to the bathroom? That's part of it. And because there's not enough to go around, water that should go to the brain is redirected to other organs, hence that headache. When dehydrated, people are at greater risk of sustaining musculoskeletal injuries such as cramps, muscle pulls and strains. This increased risk of injuries can result in reduced training time and diminished muscle gains.
Downside 2: It Can Contribute to Weight Gain
Alcohol isn't a carbohydrate, fat, or protein. It's just alcohol, or basically, a fourth macronutrient. That means that it has calories, even if you're drinking the hard stuff straight out of the bottle with no mixers. And the way alcohol consumption affects your body is different than, say, what you get from a solid dose of protein or some vegetables. At 7 calories per gram (yikes! almost the same as fat at 9 calories per gram), alcohol is also the emptiest of calories. An average alcoholic beverage is anywhere from 100-200 calories, but we all know that in drinking, one man's average is another man's warm-up, so the numbers can be much more than the average 1 drink serving size. And to be clear, all these extra calories, when not metabolized, will be stored as fat.
Downside 3: It Can Disrupt Muscle Growth
Not only does alcohol have zero nutritional value, but some studies also say it may even disrupt muscle protein synthesis, and muscle growth. (Google it if you have a day or two to kill.)
Of course, many studies are questionable, reporting only on "chronic" drinkers or even non-human subjects. That said, anyone who has taken ninth grade biology knows that alcohol is metabolized before other nutrients, blocking them from being absorbed. This can hinder protein synthesis.
Protein Synthesis
To achieve muscle growth, you must have a positive muscle protein balance. If you don't consume enough protein or exercise enough, your muscle breakdown may exceed your muscle gains, leading to a catabolic (breakdown) state in which you are losing muscle tissue. Alcohol can also put your body into a catabolic state due to its high calorie content and disruptive nature when it comes to normal bodily processes, such as protein synthesis.
Downside 4: It Interrupts Your Sleep
Alcohol can help you fall asleep, however making you feel sleepy doesn’t mean you’ll get a good night’s sleep. Drinking alcohol often leads to fragmented sleep, where you wake up several times throughout the night. Alcohol suppresses your essential REM sleep and can lead to more vivid dreams and nightmares, sleepwalking and other disruptive sleep disorders, insomnia, and even breathing problems like sleep apnea. In fact, as more alcohol is consumed, sleep quality tends to get worse.
Not to mention the morning after a night with too much alcohol: oversleeping and grogginess can really prevent you from feeling like your best self for the next day.
These sleep disturbances happen because, as your body breaks down and metabolizes the alcohol, it disrupts the natural healthy sleep cycle that helps you have a sound and restful sleep. The metabolism of alcohol is what prevents you from waking up feeling refreshed and rested.
Downside 5: Disrupted Hormone Levels
A major part of protein synthesis involves several hormones involved in the muscle-building process, namely testosterone and human growth hormone. According to a this recent study, alcohol affects the release of both of these hormones. Alcohol can negatively impact this essential hormone in two different ways, both of which can significantly short circuit muscle gains:
Alcohol has been shown to increase the stress hormone cortisol, which can reduce the levels of growth hormone by as much as 72 percent.
Growth hormone is predominately secreted during the early sleeping hours of the night. Because alcohol tends to disrupt natural sleep rhythms, it can decrease the amount of growth hormone released by as much as 70 percent.
Alcohol consumption also causes your liver to release substances that virtually cancel out the effects of testosterone in your body. The result is an environment not suitable for muscle growth.
Testosterone levels are decreased with alcohol consumption. More estrogen is created with alcohol consumption thus causing increased fat depositing, fluid retention, and gynecomastia (man boobs).
Long story short alcohol is not just about dehydration or empty calories consumed. Alcohol can mess with your hormones, sleep cycles, heart rate, and more. I am all about a celebratory drink, but keep in mind what factors could be at play when you’re shooting the boot, and the benefits to your health you could have from changing what you choose to drink.