How Alcohol Affects Your Metabolism and What You Can Do

28 June 2025

In this article, we take a closer look at the metabolic effects of drinking. Also, we’ll learn about the benefits of cutting down and even quitting alcohol.

Highlights

  • More than half of adults in England reported consuming alcohol in the past week.
  • Heavy drinking is a well-established risk factor for many health issues, including cancer, heart disease, and obesity.
  • Low energy levels and malnutrition in long-term heavy drinkers can result due to poor absorption, poor food choices, nutritional deficiencies, sleep disturbances, and impaired metabolism.
  • Quitting drinking or drinking within the limits can work wonders for your physical, mental, and emotional well-being.
  • With mindful drinking habits, clean eating, and appropriate exercise, one can enjoy alcoholic beverages without guilt, sometimes. After all, we’re humans and social animals!

Alcohol Use in the UK: A Quick Look at the Stats

In the UK, a lot of people enjoy alcoholic drinks, including beer, wine, spirits etc. According to the Commons Library Research Briefing, in 2022, (1)

  • Over 50% of adults in England reported drinking in the past week.
  • 30% of men drank more than the recommended limits.
  • Alcohol-specific deaths in the UK totalled 10,048, with alcoholic liver disease responsible for over 75% of deaths.

While moderate drinking isn’t expected to cause long-term health issues, heavy or long-term drinking has many health effects, including a higher risk of:

  • Diseases of the heart and blood vessels
  • Cancer of the oral cavity, liver, and colon
  • Diabetes
  • Malnutrition
  • Mental health issues, such as anxiety and depression
  • Impaired judgment, decision-making, and thinking
  • Road accidents
  • Domestic or public violence
  • Overweight and obesity

How Does Your Body Process Alcohol?

Once you drink alcohol, it reaches the bloodstream in two ways: through the lining of the mouth (small fraction) and via the stomach lining and small intestine.

From the circulation, alcohol travels to almost all body organs, including the brain. It takes about 30 minutes to feel the effects of alcohol, depending on how fast your body absorbs alcohol.

Our body considers alcohol a toxin. As such, it does everything to neutralise or remove the poison from the system. The liver is the primary organ that neutralises alcohol (about 90%).

In the liver, alcohol is first converted to acetaldehyde, a toxic chemical that can cause cancer. Then, another enzyme converts acetaldehyde to a less toxic substance called acetate. The liver can neutralize only one unit of alcohol per hour. Thus, if you drink more than one unit in an hour, alcohol will accumulate in the body, causing you to feel intoxicated.

How much is one unit in the UK?

In the UK, one unit of alcohol is what you find in a single shot of spirit. A can of lager/beer/cider contains about 2.4 units. Likewise, a standard glass of red/white/rosé wine contains about 2.1 units.

According to the NHS, adult men and women shouldn’t drink more than 14 units a week regularly.

How Alcohol Affects Your Metabolism

Metabolism is a series of reactions that occurs in each cell throughout the body. It helps convert what we eat and drink into energy.

Alcohol negatively affects metabolism, resulting in:

  • Impaired digestion and absorption of nutrients
  • Accumulation of toxic substances in the body
  • Malnutrition
  • Increased risk of medical conditions, such as diabetes, heart disease, and stroke 

In the following sections, we’ll learn how alcohol affects the metabolism of macronutrients—glucose, protein, and fat.

Macronutrients are nutrients that your body needs in large quantities to carry out daily activities. They provide energy to each cell of the body.

Alcohol effects on glucose metabolism

Short-term alcohol use has variable effects on blood sugar levels. It may reduce or cause no change in blood sugar levels. Factors that determine this, such as:

  • Nutritional status of the individuals at the time of drinking
  • The amount of alcohol consumed
  • Blood alcohol levels

For example, blood sugar levels typically remain unchanged if you drink after an overnight fast. However, drinking after fasting for 3 days can lead to dangerously low blood sugar levels. (2)

Long-term alcohol use dramatically reduces the amount of glucose stored in the liver. When you drink alcohol, your liver rapidly breaks down glucose stored in the liver to help maintain blood glucose levels.

On the other hand, both short- and long-term alcohol use appears to have no effect on the glucose stored in muscles.

Moderate drinkers may have a lower risk of diabetes because moderate amounts of alcohol are thought to help your cells use insulin more efficiently. Insulin is a hormone that carries sugar from the bloodstream to the cells. (3)

Contrarily, heavy drinking for prolonged periods may increase diabetes risk as heavy drinking prevents your cells from using insulin efficiently. (4)

Alcohol effects on protein metabolism

Alcohol use can lead to either increased or decreased protein, depending on specific organs and tissues.

For instance, alcohol causes our skeletal muscles to lose protein, affecting up to two-thirds of all alcohol abusers. (5)

Likewise, it reduces the amount of protein that helps your heart contract. This can lead to heart muscle disease. Similarly, brittle bones may occur due to a loss of collagen (a type of protein) from the bones.

On the other hand, increased collagen content in the liver can result in permanent liver scarring.

Alcohol effects on fat metabolism

Alcoholics tend to have lower total body fat but higher fat deposition in the stomach area (beer belly) and liver. Alcohol is thought to enhance fat breakdown. The released fatty acids then move to the liver, leading to alcoholic fatty liver disease.

Alcohol Also Affects Micronutrients

Our body needs micronutrients (vitamins and minerals) in small amounts for growth, disease prevention, and general well-being.

But did you know the pint you enjoy every day could be wreaking havoc on these essential nutrients? Several studies have consistently shown that regular drinking can lead to a deficiency of many micronutrients, including: (6)

  • B vitamins
  • Magnesium
  • Zinc
  • Selenium
  • Iron
  • Phosphorus

Further Reading, see our blog article: How Does Alcohol Affect Vitamin Absorption And Energy?

Can Drinking Cause Weight Gain?

Yes and no.

Because alcohol is calorie-dense, many of us might think that’s the only way drinking can lead to weight gain. However, alcohol is more of an enigma than a simple drink.

Studies have consistently shown that light-to-moderate drinking has no considerable effect on body weight. Nonetheless, heavy drinking has been associated with obesity in many studies. (7)

The following factors may affect the risk of weight gain from alcohol use:

  • Type of drink
  • Amount you drink
  • How often you drink
  • Genetics
  • Gender
  • Level of physical activity
  • Age
  • General health

While researchers have yet to find a clear link between drinking and obesity, alcohol might be the culprit because:

  • It makes fat burning hard.
  • It’s rich in calories (7 calories per gram; for reference, fat has 9 calories per gram).
  • It stimulates hunger and suppresses satiety.

What you take with alcohol can make you gain extra pounds

Eating habits tend to change both during and after drinking. 

In one study involving 282 college freshmen, (8)

  • 75% of the participants reported drinking in the past month.
  • Of them, 65% were “low-risk” drinkers and 35% were “moderate-risk” drinkers.
  • 50% reported overeating and making unhealthy food choices after drinking.

Alcohol shuts down the brain region that regulates decision-making and judgment. As a result, when intoxicated, you’ll be more likely to devour high-fat and salty foods.

Together with excess calories from alcohol, these calorie-dense foods can lead to weight gain.

Benefits of Cutting Down or Quitting Drinking

Cutting down or quitting drinking has several benefits to your physical, psychological, and emotional health. When you drink less or quit, you will typically have:

  • Improved mood and sleep
  • Increased energy levels
  • Improved relationships with your loved ones
  • Better performance at work
  • Decreased risk of long-term health conditions, including cancer and heart disease
  • More savings

At Clinic Nutrition, some of us drink alcohol and some don’t. If you are concerned about your level of drinking, talk to your doctor and they can help you find resources to quit.  For an interesting read , take a look at Stop Drinking Now by Allen Carr See Amazon listing  (no referral fees).

Frequently Asked Questions

  1. What happens if you drink alcohol daily?

Regular alcohol use, even within the limits, can cause damage to your liver, lungs, heart, kidneys, and pancreas. Besides, too much drinking can increase the risk of certain cancers.

  1. Does alcohol affect sperm?

Altered sperm count, size, shape, and motility are some of the common effects of heavy, long-term drinking.

  1. What are the short-term effects of alcohol?

Initially, an individual may feel relaxed and uninhibited. If they continue drinking after this point, they may experience:

  • Slurred speech
  • Unsteady gait
  • Drowsiness
  • Distorted perception
  • Memory problems

References:

  1. House of Commons Library. Alcohol statistics: England. https://researchbriefings.files.parliament.uk/documents/CBP-7626/CBP-7626.pdf
  2. Steiner, Jennifer L et al. “Impact of Alcohol on Glycemic Control and Insulin Action.” Biomolecules vol. 5,4 2223-46. 29 Sep. 2015, doi:10.3390/biom5042223
  3. Ilse C. Schrieks, Annelijn L.J. Heil, Henk F.J. Hendriks, Kenneth J. Mukamal, Joline W.J. Beulens; The Effect of Alcohol Consumption on Insulin Sensitivity and Glycemic Status: A Systematic Review and Meta-analysis of Intervention Studies. Diabetes Care 1 April 2015; 38 (4): 723–732. https://doi.org/10.2337/dc14-1556
  4. Kim, Soo-Jeong, and Dai-Jin Kim. “Alcoholism and Diabetes Mellitus.” Diabetes & Metabolism Journal, vol. 36, no. 2, Jan. 2012, p. 108, doi:10.4093/dmj.2012.36.2.108.
  5. Preedy, Victor R., et al. “Protein Metabolism in Alcoholism: Effects on Specific Tissues and the Whole Body.” Nutrition, vol. 15, no. 7–8, July 1999, pp. 604–08, doi:10.1016/s0899-9007(99)00096-9.
  6. Parrish, C. R., Peterson, B. D., Stotts, M. J., University of Virginia Health System, & University of Virginia Health System. (2021). Beyond the banana bag: Treating nutritional deficiencies of alcohol withdrawal syndrome. In PRACTICAL GASTROENTEROLOGY. https://med.virginia.edu/ginutrition/wp-content/uploads/sites/199/2021/06/Alcohol-Withdrawal-June-2021.pdf
  7. Martínez-Urbistondo, D., Perez-Diaz-del-Campo, N., Landecho, M.F. et al. Alcohol Drinking Impacts on Adiposity and Steatotic Liver Disease: Concurrent Effects on Metabolic Pathways and Cardiovascular Risks. Curr Obes Rep 13, 461–474 (2024). https://doi.org/10.1007/s13679-024-00560-5
  8. Lloyd-Richardson, Elizabeth E et al. “The relationship between alcohol use, eating habits and weight change in college freshmen.” Eating behaviors vol. 9,4 (2008): 504-8. doi:10.1016/j.eatbeh.2008.06.005