Your Guide to Alcohol and Nutrition

Two common approaches to alcohol during quarantine: ending every night with a glass (or three) or wine, or staying sober since your last in-person happy hour. What is actually going on in our bodies when we drink? Is a sober lifestyle the healthier choice? If we choose to drink, what’s the smartest way to go about it? In this article, we’ll address all of those questions, and more.

What is alcohol?

Simply put, alcohol is a compound found in wine, beer, and spirits that causes you to feel drunk. It’s known in the science world as ethanol or ethyl alcohol. It is formed through a process known as fermentation. Fermentation is when microorganisms like yeasts break down sugars. This means that every alcoholic drink stems from a sugar-rich carbohydrate. For example: wine is made from grapes, beer is made from barley, and vodka is made from potatoes.What happens when we drink alcohol?

Part 1: How does alcohol get into our blood?

Alcohol absorption starts as soon as we take our first sip (1). A small amount immediately passes through the small blood vessels in the mouth and tongue. Next, it travels down to the stomach. Here, up to twenty percent will pass through the stomach and into the bloodstream. From there, alcohol continues to the small intestine, where the remaining 75-85% of alcohol is absorbed.

Importantly, food in the stomach slows down the transit time. In other words, drinking on a full belly causes alcohol to stay in the stomach longer. This gives an enzyme in the stomach more time to break down some alcohol. This enzyme is called alcohol dehydrogenase (ADH). Research links lower ADH activity with reduced alcohol tolerance (2). Unfortunately, women have less ADH activity than men (explains a lot, right?).

Part 2: What happens to the alcohol once it’s in our blood?

Once alcohol has made its way into the bloodstream, it quickly circulates until the liver can break it down. The liver breaks down 80-90% of alcohol, but can only handle approximately one drink per hour. Meanwhile, it makes its way to other organs of the body. 

Alcohol rushes to the brain. We will experience mood changes and impaired cognition within five to ten minutes. High levels of alcohol impair movement coordination and lead to memory disruption (hello, blackouts). Very high levels of alcohol will slow breathing and result in lost consciousness or even death.

The kidneys have to work harder to filter the blood and produce more urine so that alcohol waste products can leave the body. Some alcohol evaporates from the blood, through the lungs, and out through our breath. Additionally, a small amount of alcohol evaporates from our skin through tiny blood vessels.


What factors influence how alcohol affects the body?

Ever wonder why your drinking buddy can handle three martinis, but one vodka soda knocks you out? There are many factors that play into individual reactions to drinking, particularly their rise in blood alcohol concentrations (BAC). These factors include body size, age, sex, ethnicity, and genetics (3). Frequently drinking and the presence of food in the stomach also increases tolerance. Meanwhile, consuming highly concentrated beverages and rapid drinking will cause BAC to rise at a faster rate.


How does drinking alcohol affect our health?

Brain health

The short-term effects on your brain are mentioned above. While these effects are temporary, chronic drinkers may experience permanent changes in their brains. Alcohol abuse can increase risk of dementia and even cause brains to shrink (4). On the other hand, there is research to suggest that moderate drinking might benefit cognition. For instance, one study suggests that consuming one to six drinks per week is associated with lower risk of incident dementia in older adults (5).

Heart health

Evidence show that heavy drinking increases risk of heart attacks and strokes (6). However, there is some data to suggest that moderate alcohol consumption may help reduce risk of heart disease (7). There are a few proposed mechanisms by which this may occur, including: increasing “good” HDL cholesterol, decreasing blood pressure, and reducing stress and anxiety.


Light to moderate alcohol intake might enhance insulin sensitivity (8). Insulin is the hormone responsible for uptake of blood sugar into cells. Fighting insulin resistance lowers risk of type 2 diabetes. However, heavy drinking causes risk of type 2 diabetes to rise (note any trends here?) (9).


Alcohol consumption at all levels is directly linked to increased risk of certain cancers. Specifically, mouth and throat cancer are sensitive to its effects. Just one drink per day is linked to twenty percent increased risk of these cancers (10). Meanwhile, more than four drinks will increase risk by fivefold. It might also increase risk of other cancers like breast and colon (11, 12).

Birth defects

Alcohol use is not safe before and during pregnancy (13). It can pass from the mother’s blood to the baby. This results in miscarriage, stillbirth, and a range of other disabilities. These disabilities are called fetal alcohol spectrum disorders (FASDs). Children with FASDs may have various physical and cognitive impairments. These include abnormal facial features, growth issues, central nervous system problems, and more.


How does alcohol affect your weight?

Alcohol does not provide any beneficial nutrients. However, it comes with a price: seven calories per gram.That’s almost twice as many calories as carbohydrates and protein. Moreover, alcohol provides what we call “empty calories.” Think of calories as financial investments in your body. The calories “spent” on real food give you energy, benefit your hormones, provide micronutrients, and more. The calories from drinking might benefit your social health and provide short-term satisfaction. However, they do not nourish your body like vegetables, fruits, whole grains, meat, poultry, seafood, legumes and dairy. Additionally, beverages are not satiating. For some people, drinking leads to overeating by lowering inhibition. This can contribute to weight gain.


What is the healthiest way to drink?

If you’re going to choose to drink, we recommend sticking to beverages that have little to no added sugar. This helps keep calories in check. Wine, light beer, or a spirit mixed with soda water are all good options. If you want to add a kick, we like adding lemons, limes, or a splash of real fruit juice. The research is mixed on whether or not certain types of alcohol have beneficial effects. The current scientific consensus is that the quantity is what matters the most.

Hydration is key when you’re drinking. Dehydration can worsen the effects of alcohol and lead to brutal hangovers. We recommend matching each drink to at least one eight-ounce cup of water. We also recommend ordering drinks with plenty of ice to help water them down. Electrolyte powders might also be needed to aid hydration status.

Lastly, avoid drinking on an empty stomach. As we discussed above, food helps delay alcohol’s transit time from the stomach to the intestines. This enables ADH to do its job and help kickstart the breakdown process. Bonus points if you have a meal with protein, fat and fiber. These three together help keep food in the stomach for longer and increase feelings of fullness.


The bottom line:

The verdict on alcohol is still out. This is due to various limitations in the research and many unanswered questions. For example, are the benefits of drinking lightly underestimated because some heavy drinkers are inaccurately reporting their habits? Does drinking pattern (i.e. binge drinking vs. daily consumptions) have an effect? Are smoking and recreational drug use confounding factors?

As of now, our best bet is to listen to the U.S. Dietary Guidelines recommendations (14). If you aren’t currently drinking, there is insufficient evidence for you to start. If you do choose to drink, do so moderately. Moderate alcohol consumption is defined as up to 1 drink per day for women and up to 2 drinks per day for men. Remember: one drink is a 12 ounce beer, 5 ounce wine, or 1.5 ounce spirit. However, just because the Guidelines say that moderate drinking is “healthy,” that doesn’t mean it’s healthy for you.

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