A woman stares at some shelves of wine bottlesShare on Pinterest
Experts say even moderate consumption of alcohol can lead to health issues. d3sign/Getty Images
  • Drinking alcohol can negatively affect the body.
  • Harmful use of alcohol can lead to a variety of health problems, including certain cancers.
  • Researchers from the National Institute of Health have discovered more information on how alcohol affects the small and large intestine, known as alcohol-associated bowel disease.

Drinking alcohol, even in moderate amounts, can have harmful effects on health.

How much and how often you imbibe can increase these effects, leading to health problems such as liver disease, pancreatitis, mental health issues, and certain cancers like gastric cancer and colorectal cancer.

Additionally, about 3 million deaths each year worldwide are linked to use of alcohol.

Now, researchers from the National Institute of Health are shedding more light on how alcohol can also cause damage to other areas of the gastrointestinal system, mainly the small and large intestines.

The condition is known as alcohol-associated bowel disease.

This study was recently published in the journal eGastroenterology.

When you drink alcohol, it instantly begins to affect the gastrointestinal system as it goes down your esophagus to your stomach.

In the stomach, the alcohol begins to absorb into your bloodstream. If you do not have much food in your stomach, the remaining alcohol then passes quickly into the intestines, where it continues to be drawn up into the bloodstream.

Once alcohol is in the bloodstream, it is carried to all areas and organs of the body.

The amount of alcohol in a person’s bloodstream is known as their blood alcohol concentration.

The body also instantly begins to metabolize alcohol once it enters the body. Ethanol in alcohol is broken down by the liver into a carcinogenic compound called acetaldehyde.

Although acetaldehyde is eventually broken down into acetate, and then water and carbon dioxide are expelled by the body, it can still have damaging effects before that happens.

This is what makes alcohol a significant risk factor for gastrointestinal diseases, said Dr. Luca Maccioni, a postdoctoral fellow in the Laboratory of Liver Diseases and Laboratory of Physiologic Studies at the National Institute of Health and first author of this study.

“The gastrointestinal tract is in contact with the highest amount of ethanol and its metabolites during alcohol consumption. Extremely high concentrations of ethanol and its metabolites significantly increase the risk of gastrointestinal diseases and cancers,” he told Medical News Today.

In this study, Maccioni and his team reviewed previous studies to gather more information on alcohol-associated bowel disease, which researchers say is a poorly understood condition.

“Alcohol-associated bowel disease is a spectrum of intestinal dysfunctions linked to excessive alcohol consumption,” Maccioni explained.

“To date, we lack a diagnostic definition of alcohol-associated bowel disease, as well as a detailed molecular characterization of alcohol-associated bowel disease, which could precede cancers of the digestive tract. Therefore, future studies are needed to better understand alcohol-associated bowel disease’s pathogenesis and identify therapeutic targets to treat and/or ameliorate this disease,” he said.

While researchers state the complete physical process of how alcohol-associated bowel disease happens is not entirely understood, they believe it involves the metabolism of ethanol and the metabolites acetaldehyde and acetate it creates.

“Ethanol, a main component of alcoholic drinks, is a psychoactive substance with toxic and dependence-producing properties,” said Maccioni.

“Ethanol metabolism in the digestive tract leads to the generation of acetaldehyde and acetate. Ethanol, as well as acetaldehyde and acetate produced by ethanol metabolism, may promote and/or contribute to bowel pathogenesis via different mechanisms, including gut microbiome-related changes and intestinal epithelial/immune dysfunctions,” he explained.

Previous research shows drinking alcohol is linked to an increased likelihood of developing gastric cancer. It is also correlated to a higher risk for colorectal cancer.

According to Dr. Rudolph Bedford, a gastroenterologist at Providence Saint John’s Health Center in California who was not involved in this research, much of that has to do with the carcinogens released by the alcohol when consuming it.

“These carcinogens can affect the cells in either the stomach or the colon and, quite frankly, other GI organs such as the pancreas (and) esophagus,” he told Medical News Today.

“Alcohol really causes an increased risk of cancer throughout the gastrointestinal system. Patients who drink alcohol [u]pwards of three drinks a day are at an increased risk of stomach cancer and colon cancer.”
— Dr. Rudolph Bedford

Medical News Today also spoke with Dr. Scott Friedman, the dean for therapeutic discovery, a professor of medicine and pharmacologic sciences, and the chief of the Division of Liver Diseases at the Icahn School of Medicine at Mount Sinai in New York who was not involved in the study.

Friedman discussed another potential driver of gastric and colorectal cancer — alcohol’s effect on gut bacteria.

“We’re now intensely focused on the contribution of the microbiome or the collection of bacteria in the human gut because we’re beginning to appreciate that not only are they a rich source of metabolites that can affect health, but they can interact with organs in the body,” he said.

“For example, the microbiome can generate species in some patients that percolate to the liver and can induce some liver damage,” Friedman added.

“That’s actually thought to be one of the drivers of alcoholic liver disease, which is that alcohol changes the microbiome, changes the bacteria. Those bacteria make substances that both damage the intestinal wall directly, but may also percolate through the blood into the liver where they induce damage there.”
— Dr. Scott Friedman

When it comes to lowering your risk for gastrointestinal issues, such as alcohol-associated bowel disease, gastric cancer, and colorectal cancer, Friedman said the first order of business is addressing your drinking habits.

“Alcohol abuse is damaging to the body in many ways (and) as this article points out, the underlying disease really is alcohol-use disorder,” he noted.

“Go to 12-step programs or other rehab programs to seriously tackle the addiction to alcohol so that they can reduce their intake. That is far more effective than any other treatment,” he said.

“Beyond [avoiding alcohol], a healthy diet, avoiding the overindulgence of red meats, plenty of fiber, and what we would consider really a healthy diet or a Mediterranean diet sometimes, are all things that may enhance the gut function and maintain its health.”
— Dr. Scott Friedman

Bedford said he would like to see more messaging to the general public about the effect of alcohol consumption on the gut microbiome.

“I believe this really comes down to the effect on the microbiome, on top of the other multiple effects that alcohol has, but the bacterial flora is likely manipulated (and) changed. The diversity of bacteria within the gut is probably decreased. Other mechanisms, something we call DNA methylation, is probably affected. And those are all likely factors that predispose one to many of these cancers,” he said.