Nutrients Alcohol Depletes: B Vitamins, Magnesium, Zinc and More

Heavy or regular drinking can deplete thiamin (vitamin B1), folate, vitamin B6, magnesium and zinc by reducing absorption and increasing losses, but the deficiency research is about sustained drinking rather than a single night out, and vitamin supplements haven’t been shown to prevent hangovers.1, 2, 3 For most people who drink, food covers these nutrients; people who drink heavily need a doctor, not a multivitamin.

Key takeaways

  • Up to 80% of people with chronic alcoholism develop thiamin (vitamin B1) deficiency, because ethanol reduces thiamin absorption, liver stores and activation.1
  • Low zinc status shows up in 30% to 50% of people with alcohol use disorder; alcohol cuts zinc absorption and increases the zinc lost in urine.2
  • Even 8 fluid ounces of red wine a day for two weeks significantly lowered blood folate in healthy men, though not to deficient levels.4
  • In a November 2024 survey of 46 US hangover products, 20 of the 23 containing vitamin B1, and all 22 that stated a vitamin B12 amount, exceeded the daily recommended amount, yet none had been shown to prevent or reduce hangovers.5

How does alcohol affect nutrient absorption?

Alcohol works against nutrients three ways: you absorb less, you lose more, and heavy drinking often crowds out food.4, 6

It inhibits absorption in the small intestine, raises how much folate and zinc the kidneys excrete, and interferes with how the liver stores and activates thiamin.1, 2, 4, 6 Scale matters: most of the numbers below come from chronic heavy drinking, not an occasional night out, though even moderate daily drinking can nudge folate down.4

Nutrients affected by drinking: adult needs and food sources (NIH Office of Dietary Supplements)
Nutrient How alcohol affects it Adult RDA (AI for potassium) Good food sources
Thiamin (B1) Less absorbed, stored and activated; deficient in up to 80% with chronic alcoholism1 1.2 mg men, 1.1 mg women Fortified cereal (1.2 mg), pork chop, 3 oz (0.4 mg), black beans, ½ cup (0.4 mg)
Folate Less absorbed, broken down faster, more lost in urine4 400 mcg DFE Boiled spinach, ½ cup (131 mcg), black-eyed peas, ½ cup (105 mcg)
Vitamin B6 Active form tends to be very low with alcohol dependence7 1.3 mg (ages 19–50) Chickpeas, 1 cup (1.1 mg), tuna, 3 oz (0.9 mg)
Vitamin B12 Not listed by ODS among causes of deficiency8 2.4 mcg Clams, 3 oz (17 mcg), salmon, 3 oz (2.6 mcg)
Magnesium Deficiency common with chronic alcoholism9 400–420 mg men, 310–320 mg women Pumpkin seeds, 1 oz (156 mg), almonds, 1 oz (80 mg)
Zinc Less absorbed, more lost in urine; low in 30–50% with alcohol use disorder2 11 mg men, 8 mg women Oysters, 3 oz (28–32 mg), beef sirloin, 3 oz (3.8 mg)
Potassium Vomiting and diarrhea can lower it10 3,400 mg men, 2,600 mg women Lentils, 1 cup (731 mg), baked potato (610 mg), banana (422 mg)

Thiamin (B1): the most important one

Thiamin deficiency is the most serious nutrient problem tied to drinking: ODS says chronic alcohol use disorder appears to be its most common cause in high-income countries, and up to 80% of people with chronic alcoholism develop it.1

The worst outcome is Wernicke-Korsakoff syndrome, 8 to 10 times more common in people with chronic alcoholism, which can bring severe short-term memory loss, disorientation and confabulation (filling memory gaps with made-up stories).1 Confusion and unsteady movement in someone who drinks heavily need prompt medical care; ODS describes clinicians treating those patients with thiamin.1

Folate, B6 and B12

Folate and B6 are clearly affected by drinking; B12 much less so.4, 7, 8

Folate. Low folate turned up in more than 60% of people with chronic alcoholism in one Portuguese evaluation, and 8 ounces of red wine or 2.7 ounces of vodka a day for two weeks lowered blood folate in healthy men, though not below the cutoff for adequacy.4 The upper limit for folic acid is 1,000 mcg a day, and high intakes may mask a B12 deficiency.4

Vitamin B6. Acetaldehyde reduces how much active B6 (PLP) cells make, and ODS says people with alcohol dependence might benefit from supplements. More isn’t better: the upper limit is 100 mg a day, and 1 to 6 grams a day for a year or more has caused nerve damage.7

Vitamin B12. ODS doesn’t list alcohol among the main causes of B12 deficiency; it highlights stomach-acid medicines and metformin instead.8

Magnesium and zinc

Both run low in many people who drink heavily, for the same reason: less in, more out.2, 9

Magnesium deficiency is common in chronic alcoholism, driven by poor diet, vomiting and diarrhea, and kidney losses. Supplements have an adult upper limit of 350 mg a day; high doses cause diarrhea and cramping.9 Zinc is low in 30% to 50% of people with alcohol use disorder. Its upper limit is 40 mg a day, and 50 mg or more for weeks can block copper absorption.2 In one small study, among 13 hangover-prone social drinkers, more dietary zinc and niacin went with milder hangovers, but the finding is only a correlation.11

Potassium and sodium

Alcohol makes you urinate more by suppressing vasopressin, but in most people electrolyte balance returns once the alcohol wears off, and the size of the disruption doesn’t track hangover severity.12

Vomiting and diarrhea can lower potassium.10 The 2025–2030 Dietary Guidelines call sodium and electrolytes essential for hydration, with a sodium limit under 2,300 mg a day.13 See electrolytes for a hangover. Vomiting after heavy drinking can also be a sign of alcohol poisoning.14

Food first: which meals replenish these nutrients?

A varied diet covers all of these for most people: beans and lentils (thiamin, folate, magnesium, potassium), leafy greens (folate, magnesium), fish (B6, B12), and beef or shellfish (zinc).1, 2, 4, 7, 9 Eating before you drink also slows alcohol absorption.15 See the best foods for a hangover and how alcohol affects your gut.

When do supplements make sense?

Mainly when a clinician finds or suspects a deficiency, which is most likely with long-term heavy drinking; thiamin and B6 are the examples ODS describes.1, 7 For everyone else, food comes first, and megadoses carry their own risks.2, 7

The current guideline is simple: “Consume less alcohol for better overall health.” Some people shouldn’t drink at all, including anyone pregnant or taking interacting medicines, and no one should drive after drinking.13 See also liver support after drinking.

Why don’t B vitamins in hangover pills prevent hangovers?

Because no good trial has shown they do, and a hangover isn’t a vitamin deficiency.3, 12, 18

In a November 2024 survey of 46 US hangover products, 20 of the 23 products containing vitamin B1 and all 22 that stated a vitamin B12 amount exceeded the daily recommended amount. Of 14 products with zinc, 5 exceeded the amount recommended for men and 8 the amount for women. The authors concluded that the ability to prevent or reduce hangover “has not been demonstrated for any product on the US hangover market.”5 Systematic reviews in 2005 and 2022 found no remedy with convincing evidence.3, 18 NIAAA: “There is no cure for a hangover other than time.”12 See pure DHM vs. hangover blends and do hangover pills work?

What we don’t know yet

How much moderate drinking affects nutrient status over years is less clear than the data on heavy drinking, and the two-week folate finding came from a small group of healthy men.4 No well-designed trial has shown that topping up a nutrient changes how you feel after drinking.18

Frequently asked questions

What vitamins does alcohol deplete?

Mainly thiamin (B1), folate and vitamin B6, plus the minerals magnesium and zinc. Alcohol reduces absorption and increases losses, and the effects are largest with regular heavy drinking.1, 2, 4, 7, 9

Do B vitamins help hangovers?

There’s no good evidence they do. Systematic reviews in 2005 and 2022 found no remedy with convincing evidence, and a 2025 market survey found no US hangover product had shown it prevents or reduces hangovers.3, 5, 18

Should people who drink take magnesium?

Most people can get enough from seeds, nuts, spinach and beans. Deficiency is common in chronic alcoholism, which calls for a doctor. Supplements have an adult upper limit of 350 mg a day, and high doses can cause diarrhea and cramping.9

Is thiamine deficiency common in drinkers?

In chronic heavy drinkers, yes: up to 80% of people with chronic alcoholism develop it. Confusion or unsteady walking in someone who drinks heavily needs prompt medical care.1

Sources

  1. NIH Office of Dietary Supplements (ODS). Thiamin: Fact Sheet for Health Professionals. Updated February 9, 2023. ODS
  2. NIH Office of Dietary Supplements (ODS). Zinc: Fact Sheet for Health Professionals. Updated January 6, 2026. ODS
  3. Pittler MH, Verster JC, Ernst E. Interventions for preventing or treating alcohol hangover: systematic review of randomised controlled trials. BMJ. 2005;331(7531):1515–1518. PMID 16373736. PubMed
  4. NIH Office of Dietary Supplements (ODS). Folate: Fact Sheet for Health Professionals. Accessed October 9, 2026. ODS
  5. Verster JC, Zijlstra MN, Barré Q, Schulz SE, Išerić E, Scholey A. The alcohol hangover product market of the United States of America. Drug Science, Policy and Law. 2025. doi:10.1177/20503245251355868. SAGE
  6. Thomes PG, Rasineni K, Saraswathi V, et al. Natural recovery by the liver and other organs after chronic alcohol use. Alcohol Research: Current Reviews. 2021;41(1):05. PMID 33868869. PubMed
  7. NIH Office of Dietary Supplements (ODS). Vitamin B6: Fact Sheet for Health Professionals. Updated June 16, 2023. ODS
  8. NIH Office of Dietary Supplements (ODS). Vitamin B12: Fact Sheet for Health Professionals. Updated July 2, 2025. ODS
  9. NIH Office of Dietary Supplements (ODS). Magnesium: Fact Sheet for Health Professionals. Updated January 6, 2026. ODS
  10. NIH Office of Dietary Supplements (ODS). Potassium: Fact Sheet for Health Professionals. Updated June 2, 2022. ODS
  11. Verster JC, Vermeulen SA, van de Loo AJAE, et al. Dietary nutrient intake, alcohol metabolism, and hangover severity. Journal of Clinical Medicine. 2019;8(9):1316. PMID 31461972. PubMed
  12. NIAAA. Hangovers. Updated December 2025. NIAAA
  13. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2025–2030. Released January 7, 2026; “Limit Alcoholic Beverages,” p. 4. PDF
  14. National Institute on Alcohol Abuse and Alcoholism (NIAAA). Understanding the Dangers of Alcohol Overdose. Updated December 2025. NIAAA
  15. Cederbaum AI. Alcohol metabolism. Clinics in Liver Disease. 2012;16(4):667–685. PMID 23101976. PubMed
  16. Substance Abuse and Mental Health Services Administration (SAMHSA). SAMHSA’s National Helpline. Accessed October 9, 2026. SAMHSA
  17. MedlinePlus (U.S. National Library of Medicine). Alcohol withdrawal. Reviewed January 1, 2025. MedlinePlus
  18. Roberts E, Smith R, Hotopf M, Drummond C. The efficacy and tolerability of pharmacologically active interventions for alcohol-induced hangover symptomatology: a systematic review of the evidence from randomised placebo-controlled trials. Addiction. 2022;117(8):2157–2167. PMID 34972259. PubMed

Published by Fuller Health, which makes After Party. This article is general information, not medical advice: talk to a doctor or pharmacist about your own health, medicines and drinking. Last reviewed October 9, 2026. How we research and write.

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