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Alcohol

Table of Contents

How alcohol accelerates biological aging
Alcohol and cancer: a classified carcinogen
Sleep architecture and recovery
The "moderate drinking" myth
Practical takeaways for longevity

How alcohol accelerates biological aging

Alcohol doesn't just damage the liver. It accelerates aging at the cellular level through multiple, well-documented pathways. A 2022 Mendelian randomization study from Oxford found that alcohol directly shortens telomeres, the protective caps on chromosomes that determine how fast cells age ^[1]. Drinking more than 29 units per week was associated with one to two years of additional biological aging compared to light drinkers. People with alcohol use disorder showed epigenetic age acceleration of over two years on next-generation aging clocks ^[2].

The mechanism is straightforward: when your liver breaks down ethanol, it uses NAD+ as a cofactor. This depletes cellular NAD+ levels and shifts the NADH/NAD+ ratio, directly impairing sirtuin activity. Sirtuins are the proteins responsible for DNA repair, mitochondrial function, and stress resistance. In short, every drink competes with your body's repair systems for the same fuel ^[3].

Alcohol and cancer: a classified carcinogen

The International Agency for Research on Cancer (IARC) classifies alcohol as a Group 1 carcinogen, the same category as tobacco and asbestos ^[4]. This isn't a marginal risk. Roughly 5.5% of all new cancer cases worldwide are attributable to alcohol. The dose-response relationship is linear for breast cancer and colorectal cancer, meaning there is no "safe" threshold below which risk disappears.

Acetaldehyde, the first breakdown product of ethanol, is the primary culprit. It damages DNA directly, increases oxidative stress, and raises estrogen levels (relevant for breast cancer risk). Even one drink per day measurably increases breast cancer risk by about 7-10% ^[5].

Sleep architecture and recovery

Alcohol is one of the most common sleep disruptors, and poor sleep accelerates aging. A 2024 systematic review confirmed that even low doses (around two standard drinks) suppress REM sleep and fragment sleep architecture ^[6]. REM sleep is when your brain consolidates memories, processes emotions, and clears metabolic waste. Losing it consistently compounds cognitive decline over time.

For anyone focused on physical performance or recovery, alcohol also suppresses muscle protein synthesis and impairs glycogen replenishment. Post-exercise recovery suffers measurably after even moderate drinking.

The "moderate drinking" myth

For decades, observational studies suggested that moderate drinkers lived longer than abstainers. This finding shaped public health messaging for a generation. It was also largely wrong. The apparent benefit came from a methodological flaw: many "non-drinkers" in older studies were former heavy drinkers who had quit due to health problems, dragging down the abstainer group's outcomes ^[7].

When researchers corrected for this using Mendelian randomization (a technique that removes confounding by using genetic variants as natural experiments), the protective effect vanished. A 2024 study published in Scientific Reports found no lifespan benefit from any level of alcohol consumption ^[8]. The WHO now states plainly: no level of alcohol consumption is safe for health.

Practical takeaways for longevity

If you currently drink, reducing intake is one of the highest-impact changes you can make for healthspan. The benefits of cutting back are measurable within weeks: improved sleep quality, lower resting heart rate, better HRV readings, and reduced inflammation markers. Complete abstinence isn't necessary for everyone, but the evidence supports keeping consumption as low as possible. If you don't drink, there is no longevity-based reason to start.

References

Track your biological age after cutting back

Epigenetic clocks show measurable biological age acceleration in regular drinkers. If you reduce or quit alcohol, track biomarkers like HRV, resting heart rate, and inflammatory markers (hsCRP) to see the reversal in real time.

www.nature.com

Protect your deep sleep

Even two drinks suppress REM sleep and fragment sleep architecture. If you do drink, stop at least 3-4 hours before bed. Better yet, use a sleep tracker to see the difference between alcohol and alcohol-free nights yourself.

pubmed.ncbi.nlm.nih.gov

Know your cancer risk honestly

Alcohol is a Group 1 carcinogen (IARC), same classification as tobacco. One drink per day raises breast cancer risk by 7-10%. There is no threshold below which the cancer risk is zero. Factor this into your personal risk assessment.

www.cancer.gov

Understand the NAD+ trade-off

Every drink depletes NAD+, the same molecule your sirtuins need for DNA repair and mitochondrial maintenance. If you're taking NMN or NR supplements to boost NAD+, alcohol directly counteracts that investment.

pmc.ncbi.nlm.nih.gov

Don't drink after training

Alcohol suppresses muscle protein synthesis and impairs glycogen replenishment. If you train for strength or endurance, drinking within 24 hours of a workout measurably reduces your gains. Time your social drinking away from training days.

Is moderate drinking actually good for longevity?

No. The earlier studies suggesting moderate drinkers live longer were flawed. Many "non-drinkers" in those studies were actually former heavy drinkers who quit due to illness, making the abstainer group look unhealthier. Mendelian randomization studies, which remove this bias by using genetic data, found no lifespan benefit at any consumption level. A 2024 study in Scientific Reports confirmed this finding.

Does alcohol make you age faster?

Yes, measurably. Research from Oxford using genetic data showed that alcohol shortens telomeres, the protective chromosome caps that shorten with aging. Heavy drinkers showed one to two years of additional biological aging. Epigenetic clock studies found that people with alcohol use disorder had a biological age over two years older than their calendar age. These are direct, causal effects confirmed by methods that control for lifestyle confounders.

Is red wine better for health than other alcohol?

The supposed benefits of red wine were largely a confounding effect. Wine drinkers tend to have higher incomes, eat more vegetables, and exercise more than beer or spirits drinkers. When researchers controlled for these lifestyle factors, the advantage disappeared. Resveratrol, the compound often credited for wine's benefits, is present in far too small amounts in wine to have any meaningful biological effect. You'd need hundreds of glasses daily to reach a therapeutic dose.

How long does it take to reverse alcohol's aging effects?

Some effects reverse quickly, others take longer. Sleep quality typically improves within days of stopping. Liver enzymes normalize within weeks. Inflammatory markers like hsCRP drop within 2-4 weeks. Telomere shortening, however, is not easily reversible. Epigenetic changes may partially reverse over months to years of abstinence, but the research on long-term reversal is still ongoing.

Does alcohol cancel out the benefits of NMN or NAD+ supplements?

Partially, yes. Alcohol metabolism directly consumes NAD+ in the liver, working against what NMN and nicotinamide riboside supplements are designed to boost. While supplements still raise baseline NAD+ levels, regular drinking forces your body to divert that NAD+ toward ethanol detoxification instead of DNA repair and sirtuin activation. It's a direct biochemical trade-off.