Another not-so-fun fact? Alcohol can reduce the integrity of the intestinal barrier, which paves way for more environmental toxins to enter your body.
Before we uncork that issue, let’s take a step back and review the basic function of the gastrointestinal tract and what happens when your intestinal lining becomes “leaky.
The cells that line your intestines act as an insanely fine sieve. They allow tiny digested nutrients — such as the breakdown products of carbohydrate, protein, and fat — to pass into your bloodstream while directing larger undigested food, toxins, and harmful microorganisms (collectively called “endotoxins”) towards the toilet.
Research shows alcohol consumption can damage the structure of this vital sieve. As a result, more endotoxins may wind up inside your body.
Since your intestines are your body’s first line of defense against ingested endotoxins, you might think they would be thick and sturdy. In reality, the gut barrier is made of a single continuous layer of cells. If those cells, or the proteins that hold them together (called tight junctions), become damaged, the holes of the sieve grow wider. That means larger, potentially harmful molecules can slip into the bloodstream, activate the immune system, and cause inflammation all over the body. This type of damaged cell barrier is referred to as increased intestinal permeability, or more informally as “leaky gut”.
We have lots to learn about leaky gut, but evidence points to alcohol as a clear cause of increased gut permeability. Acetaldehyde, a breakdown byproduct of alcohol, directly damages the intestinal lining. Chronic alcohol consumption exposes the gut to acetaldehyde, which eventually increases intestinal permeability. The resulting influx of endotoxins contributes to liver disease and other organ damage.
One interesting study found that plasma levels of endotoxins were 5-fold greater in alcoholics than in healthy controls who consume ≤1 serving of alcohol daily. This research suggests that alcohol abuse significantly disrupts the intestinal barrier — whereas light-moderate intake may not have such a negative effect.
Now, you might be wondering what happens in the gut of a healthy person who enjoys an occasional drink? In other words, do I need to ditch the rosé this Summer? A 2015 randomized clinical trial sought the answer by giving 15 healthy male volunteers a glass of wine on one day and a glass of water on another.
First, the bad news: blood tests showed that a single serving of alcohol damages the intestinal lining immediately after consumption and continues to do so for up to 2.5 hours.
The (barely) good news: The damage was not enough to initiate an immune response or allow harmful substances to pass into the bloodstream.
The Bottom line: While you should not fear an occasional drink, don’t let your glass of rosé turn into a whole bottle.
For healthy individuals, it is regarded as safe for women to drink up to one alcoholic beverage per day and for men to have no more than two servings per day. However, consider drinking alcohol only a few times a week at most so your gut has time to heal between nights out.
Click here to learn more about the effects of alcohol on your health.
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