Hangovers: What Causes Them and What Actually Helps

By the KABO Nutrition Team · fact-checked against cited public-health sources.

A hangover is dehydration, disrupted sleep, inflammation and the toxic byproduct of alcohol metabolism arriving together. No food or drink cures it — only time does. What genuinely helps is fluid with electrolytes, food, and rest; what does not is a morning drink or a ‘detox’ anything.

Key takeaways
  • Acetaldehyde, dehydration, poor sleep and inflammation all contribute.
  • Alcohol suppresses a hormone that conserves water, so you lose more than you drink.
  • Alternating alcohol with water during the evening is the single most effective step.
  • Nothing cures a hangover; time is the only actual treatment.
  • ‘Hair of the dog’ postpones the hangover rather than removing it.

Four separate problems wearing one name

Alcohol is metabolised first to acetaldehyde, a compound considerably more toxic than alcohol itself, before being broken down further. Acetaldehyde accumulation is a significant contributor to how you feel the next morning.

Alcohol also suppresses vasopressin, the hormone that tells the kidneys to conserve water — which is why you urinate more than the volume you drank, and wake up genuinely dehydrated, with electrolytes lost alongside.

It disrupts sleep architecture: you may fall asleep quickly, but deep and REM sleep are suppressed, so a full night in bed delivers poor-quality rest. And it triggers a low-grade inflammatory response that accounts for a good share of the malaise and headache.

There is a fifth factor worth naming: a meaningful proportion of people of East and South-East Asian descent carry a variant that slows acetaldehyde clearance, producing flushing and severe reactions from small amounts. That is a genetic difference, not a tolerance one.

What genuinely helps the morning after

  • Fluid with electrolytes — ORS, nimbu paani with salt and sugar, coconut water.
  • Food, particularly carbohydrate and protein; blood glucose is often low.
  • Sleep, which is the only thing that addresses the sleep debt.
  • Simple painkillers if needed — but never paracetamol in quantity, since it is processed by the same liver under load.
  • Time. This is the actual treatment; everything else manages symptoms.

Indian kitchens have reasonable options here: nimbu paani, curd rice, khichdi, rasam, buttermilk with salt, and idli are all easy on the stomach and replace fluid and salt at the same time.

What does not work

“Hair of the dog” delays withdrawal by topping up blood alcohol. The hangover arrives later and, if the pattern repeats, it is a recognised warning sign rather than a remedy.

Detox drinks, cleanses and liver tonics do nothing that the liver is not already doing. There is no product that speeds alcohol clearance — the rate is essentially fixed at roughly one standard drink per hour.

Coffee helps alertness and nothing else; it is also a mild diuretic when you are already dehydrated. A sweaty workout to “sweat it out” worsens dehydration and is not advisable.

Prevention, which is the only reliable lever

  • Alternate each alcoholic drink with a glass of water — the highest-yield habit by far.
  • Eat properly before and during; food slows absorption considerably.
  • Drink slowly; the liver processes roughly one standard drink per hour regardless of pace.
  • Prefer clearer spirits — darker drinks carry more congeners, which worsen hangovers.
  • Drink a glass or two of water and eat something before sleeping.
  • Set a limit before you start rather than during.

The larger picture

It is worth being straightforward: alcohol has no established safe level for health, and the WHO position is that risk begins with the first drink. Established associations include several cancers, liver disease and cardiovascular harm.

That does not mean the only acceptable advice is abstinence — many people drink moderately and will continue to. But hangover advice framed as harm reduction should not quietly imply that the underlying activity is neutral.

Frequent hangovers, drinking to relieve them, or an inability to stop once started are worth discussing with a doctor rather than managing with better hydration.

Frequently asked questions

Does eating before drinking prevent a hangover?

It slows alcohol absorption and reduces peak blood alcohol, which helps. It does not prevent a hangover if you drink enough.

Is beer less likely to cause a hangover than whisky?

Darker drinks contain more congeners, which are associated with worse hangovers. But total alcohol consumed is the dominant factor by a wide margin.

Do electrolyte drinks cure a hangover?

They address the dehydration and electrolyte losses, which is part of the picture. They do nothing about acetaldehyde, disrupted sleep or inflammation.

References

  1. World Health Organization, Healthy diet fact sheet. who.int
  2. ICMR-NIN, Dietary Guidelines for Indians (2024). nin.res.in

Related reading

More on this topic: Energy, Sleep & Stress · Browse all nutrition topics

Back to blog