Is Fasting on a Hangover a Good Idea?

I bet you know the feeling: getting up on a Sunday with a massive hangover, asking yourself should I fast today or not? To me, the first thing that comes to mind is always: I need high carbs, greasy junk food to soak all this alcohol. But do you really?

So is fasting on a hangover good or bad for you? Nothing indicates that fasting would have either a negative nor a positive effect on your body on a hangover. Your liver will spend the day detoxifying the alcohol. You’re dehydrated and in hypoglycemia: drink a lot of water and it might even help to carb load since you’re experiencing low blood sugar.

There are tons of other elements that go into a hangover and your body’s reaction to it. It’s important to comprehend the effect of a hangover and fasting to better choose what you should do.

The effects of fasting on a hangover

Before jumping into the effect fasting might have when hungover, what exactly happens to your body when you’re in that dreadful state?

As explained above, the most common explanation is simply that being hungover puts you in a dehydrated state. Alcohol acts as a diuretic, increasing the production of urine and inhibiting the pituitary secretion of anti-diuretic hormone (ADH for short). Those reduced levels prevent the kidney from reabsorbing water, which results in dehydration.

But on that subject, one study has shown that there seems to be no correlation between dehydration levels and the severity of a hangover. So while dehydration is definitely a cause for that state, it’s not the only explanation.

Another cause of a hangover, for most scientists, comes from the way alcohol interferes with your body’s natural chemical balance. Resulting in your cells no longer being capable of performing several metabolic activities. Like absorbing glucose from the blood or regulating electrolyte levels.

But once again, the same study shows people with hangover don’t seem to have lower levels of electrolytes or glucose in the blood.

Another suspect could be acetaldehyde, a toxic compound in the body. Ethanol is broken down by enzymes in the liver into those acetaldehydes, which are found to be 10 to 30 times more toxic than alcohol. Normally, they are broken down quickly into acetate (which isn’t toxic) and then into carbon dioxide and water. But drinking lots of alcohol slows this process down and acetaldehydes can build up in the body. This alone could explain symptoms such as sweatiness, nausea or vomiting.

One of the last things on the list of suspects is also the way alcohol messes with your immune system. Cytokines, a molecule used by the immune system for signaling, can be released upon drinking too much. This molecule is generally released to trigger a fever of inflammatory response to battle an infection. This reaction can then provoke headaches, muscle fatigue or nausea.

So with all that in mind, where exactly does fasting fit in? Well it doesn’t, really. What’s important to know is that your body is in a toxified state on a hangover. Your immune system is acting out, you’re dehydrated and you have low blood sugar.

The toxic alcohol metabolism – Source

In this state, your liver primary goal will be to kick the alcohol out of your system. To detoxify you. That doesn’t allow much space for ketosis and fat burning. If it takes your liver a day to clean your body of the poisoning, you’re not going to get in ketosis as fast obviously.

So your fasting day might have been for nothing since fat burning and the detox effects of a fast aren’t accounted for by your body in the same way. Plus it will be extra hard for you to fast in that state.

I’m not saying you should eat like a pig, because, who cares. And fasting won’t have a negative effect on your body. But don’t guilt you into an awful day. You’ve already done a pretty unhealthy thing, eating normally the next day, with carbs, might help you get through the day. And you will definitively be more energized with some food and glucose since you probably won’t be in ketosis for the day.

But all the science on this subject is rather foggy, I’m extrapolating on what I read about it, and the way I handle hangovers. There are no great benefits to fasting when hungover and it might even make you shittier, so why bother? I know I don’t.

Why would eating be better on a hangover?

It’s not specifically eating that can help a hangover it’s rather what you eat that could do the trick.

I believe indulging in junk food could have a liberating effect and the rise of sugar would help. Not in any healthy way of course, but you’ll definitely feel better after a sugar rush. Since we’re all addicted anyway.

A typical “I don’t give a f***” meal for me on a hangover

You could, however, replace junk food with fruit or fruit juice to be extra efficient. The fructose you find in fruits can replace glucose, which has been lost and give you the energy to process the alcohol still in your blood.

It might not help your overall condition and symptoms, but it’ll definitely help redress the biological imbalances caused by massive drinking.

As I said before, carb-loading might help. Since you have low blood sugar, eating bread, pasta, etc. can aid you to regain some energy.

Anything with amino acids can help too. Especially cysteine, which can be found in eggs for example. This amino acid helps to break down acetaldehyde, the toxic enzyme we talked about earlier. It might relieve your liver of some of the workload.

You’re also depleted of some important minerals when drinking. So restoring those levels should also be on your to-do list. You could, for example, eat bananas for potassium, pickles for sodium and nuts for magnesium.

It’s common to think you should eat loads of fat on a hangover, but not really. You could, however, have a greasy dinner before indulging in a drinking night. It might slow the rate at which you’ll absorb alcohol. Thus reducing intoxication.

Getting back to intermittent fasting after a hangover

I have absolutely no data on this subject. Once your body has detoxified himself of the alcohol, you should go back to feeling normal. Of course depending on the hangover, how you generally handle them and how often you have them, it could take you a few days to adjust.

But the alcohol shouldn’t take more than 24 hours to be kicked out of your body. Unless you’re a really heavy drinker and you’re drinking on a regular basis. So even if you still feel shitty and down, going back to fasting the next day shouldn’t be too hard.

You shouldn’t wait to be perfectly OK before getting back on track. Force yourself to fast the next day. You’ll get your energy back rapidly and ketosis will always feel better than the drowsiness that comes with a big plate of pasta.

Moreover, stay active. This also goes when hungover. If you’re feeling bad, go outside, take a walk, be active, engage with people. Your first reaction might be to sleep in front of the TV, but I really advise you against that. Being lethargic isn’t going to help you.

Staying active will help reduce muscle ache, occupy your mind with something else, etc. I’d advise against an actual workout. Keep your exercises on a hangover day light, since you’ll already have sore muscle and low magnesium levels. Do it, but don’t push it.

Being active the next day is really important too. Of course, you should be exercising as much as possible, so don’t say to yourself: “It’s been a hard weekend, I’ll skip a day”.

Some of the tools of torture I use – lightly – on a hangover

I exercise first thing in the morning and some Mondays, I’m really not proud of myself, sweating and panting like on overweight drunk. But still, once it’s done it’s really worth it. Physically of course, but it’ll also have a great effect on you mentally.

Exercising is great and coupled with intermittent fasting or keto, it’s plain awesome. You’ll get in ketosis faster with exercise and you’ll lose more fat and less muscle. If you’re getting back on track with fasting, get back on track with your exercise routine too.

Related questions

Does sleep help on a hangover? When you go home drunk, you generally fall asleep within seconds. Alcohol is a quite powerful sedative, but you actually don’t get any good quality sleep in that condition. Still, you should avoid taking a nap on a hangover day. Just get through the detoxifying of your liver and then have a good night’s sleep. Everything will be easier the next day.

Is there a way to accelerate the process of detox on a hangover? As I mentioned, some food can help. To that list, you could add Curcuma, which is a natural anti-inflammatory. But your body recovers in its own time. If taking aspirin can help remove headaches and nausea, it doesn’t mean alcohol gets kicked out of your system any faster.

About me

I’m Thierry, a binge eating, alcohol drinking, party making, intermittent faster experimenting with keto, short and long fasts, etc.

I’m by no mean a doctor nor pretending to be one, I’m just an ordinary guy fascinated with these subjects. I compile in this blog informations, studies, content, etc. I read, listened to or watched since I first started intermittent fasting in 2007.

I hope these articles will help you !