HOW ALCOHOL AFFECTS YOUR BODY AND BRAIN

Alcohol and glucose spikes

As you can see in the graph below, alcohol can reduce glucose spikes when paired with food, but this is actually a "fake" benefit. We see this because the liver prioritizes breaking down alcohol over managing glucose, leading to lower spikes but greater strain on the liver.

The truth about alcohol

Ethanol, the main component in alcohol, is a toxin processed by the liver. During its breakdown into acetylaldehyde (toxic) and then acetic acid (non-toxic), both ethanol and acetylaldehyde cause cellular damage.

So what happens in the brain?

Alcohol crosses the blood-brain barrier, releasing dopamine (pleasure) and serotonin (happiness). That's why some people get that buzz on a night out. But alcohol also leads to long-term damage, including neuron death, DNA damage, and accelerated brain aging. Even moderate drinking, as little as one drink a day, can shrink the brain and impair cognitive function over time (read study).

Alcohol also has damaging effects on the rest of the body:

• It's a Group 1 carcinogen, which means it's linked to multiple cancers, like breast, liver, and colon cancers. This is the highest-risk group and includes other known carcinogens like asbestos, radiation, and tobacco. The more alcohol you drink, the greater your risk for these cancers, and this is due notably to the fact that alcohol creates DNA mutations. And cancers start with DNA mutations. (read study)
• It damages gut health, leads to nutrient deficiencies, causes leaky gut syndrome, and kills beneficial gut bacteria. (read study)
• It impacts fertility and hormonal balance in both men and women. (read study)
• It worsens sleep by reducing the amount and quality of restorative sleep we get. (read study)

The "one drink a day" myth

For years, it was widely believed that having one drink a day was good for heart health, but this was based on flawed studies. These studies included former heavy drinkers and individuals with health issues in the “non-drinker” category, making those who drank moderately appear healthier by comparison. Recent research has debunked this myth, showing that even one drink a day can harm the brain.

Two major studies from 2022 revealed that just one drink daily is linked to brain shrinkage, cognitive decline, and neuron loss—essentially accelerating the natural aging of the brain (read studies here and here). Additionally, when confounding factors were removed, alcohol's supposed benefits for heart health disappeared. The conclusion is clear: there is no amount of alcohol that can be considered healthy, and even light drinking comes with significant risks.

Tips if you drink alcohol

So now we know for a fact that alcohol is bad for us. It's a pleasure decision, not a health decision. Here are some tips if you want to drink for pleasure:

• Pace yourself. Drink as slowly as possible so that you don’t have more unprocessed ethanol and acetyladlehyde in your body as your liver processes them.
• Eat food. This helps slow down the arrival of ethanol in the liver. So before you drink, eat a mixed meal with protein, fat, and fiber. If you’re not sure what to eat check out my Recipe Club. 
• Exercise. The most protective thing against all the bad side effects of alcohol is working out regularly. This seems to even help reduce the impact on cancer risk of drinking! A 2017 study showed that regular vidgourous exercise nullifies the effect on cancer risk.
• Avoid drinking close to bedtime to prevent sleep disruption
• Eat fermented foods like kimchi to replenish your microbiome that’s been damaged. 
• If you’ve been drinking, have a savoury breakfast centered around protein the next day to help your body not have glucose spikes to deal with again.

The scientific studies mentioned in this episode

Biddinger K J et al., “Association of Habitual Alcohol Intake With Risk of Cardiovascular Disease.” JAMA network open 5, no. 3 (2022): e223849. https://pubmed.ncbi.nlm.nih.gov/35333364/

Daviet R et al., "Associations between alcohol consumption and gray and white matter volumes in the UK Biobank." Nature Communications 13 (2022): 1175. https://www.nature.com/articles/s41467-022-28735-5

Dufouil C et al., “Influence of apolipoprotein E genotype on the risk of cognitive deterioration in moderate drinkers and smokers.” Epidemiology (Cambridge, Mass.) 11, no. 3 (2000): 280-4. https://pubmed.ncbi.nlm.nih.gov/10784244/

Ebrahim I O et al., “Alcohol and sleep I: effects on normal sleep.” Alcoholism, clinical and experimental research 37, no. 4 (2013): 539-549. https://pubmed.ncbi.nlm.nih.gov/23347102/

Elamin E et al. “Ethanol impairs intestinal barrier function in humans through mitogen activated protein kinase signaling: a combined in vivo and in vitro approach.” PloS one 9, no. 9 (2014): e107421. https://pubmed.ncbi.nlm.nih.gov/25226407/

Fan D et al., "Female alcohol consumption and fecundability: a systematic review and dose-response meta-analysis." Scientific Reports 7 (2017): 13815. https://www.nature.com/articles/s41598-017-14261-8

Ham B J and Choi I, "Psychiatric implications of nutritional deficiencies in alcoholism."Psychiatry Investigation 2, no. 2 (2005): 44. https://www.psychiatryinvestigation.org/m/journal/view.php?number=744

Holford N H, “Clinical pharmacokinetics of ethanol.” Clinical pharmacokinetics 13, no. 5 (1987): 273-92.https://pubmed.ncbi.nlm.nih.gov/3319346/

Perreault K et al., “Does physical activity moderate the association between alcohol drinking and all-cause, cancer and cardiovascular diseases mortality? A pooled analysis of eight British population cohorts”. British Journal of Sports Medicine 51 (2017): 651-657.https://bjsm.bmj.com/content/51/8/651

Neupane S P et al., “Cytokine Changes following Acute Ethanol Intoxication in Healthy Men: A Crossover Study”. Mediators of Inflammation, no. 2 (2016): 1-7.https://onlinelibrary.wiley.com/doi/10.1155/2016/3758590

Ramchandani V et al., "A genetic determinant of the striatal dopamine response to alcohol in men." Mol Psychiatry 16 (2011): 809–817. https://www.nature.com/articles/mp201056

Shield K D et al., “Alcohol Use and Breast Cancer: A Critical Review.” Alcoholism, clinical and experimental research 40, no. 6 (2016): 1166-81. https://pubmed.ncbi.nlm.nih.gov/27130687/