Meat Withdrawal: Symptoms & Side Effects of Not Eating Meat


Meat withdrawal is what can happen when you stop eating meat. Withdrawal from meat can cause negative side effects like headaches and sleeping problems, although it varies from person to person.

When you’ve depended on something for most (if not all) of your life, and suddenly take it away, there are going to be consequences.

In the case of meat withdrawal, there are both potential benefits and side effects from suddenly going off meat.

I’ll give you an overview of both the good and the bad in this post.

Negative Side Effects of Not Eating Meat

meat withdrawal symptoms

In the long run, there are no negative side effects of not eating meat, as long as you take a vegan vitamin B12 supplement.

B12 is the only nutrient in meat that isn’t commonly found in plants (unless you eat algae or dirty produce).

However, there are some potential short term negative side effects if you suddenly stop eating meat.

I’ve divided those side effects into 2 main categories: psychological and physiological.

Psychological Side Effects of Not Eating Meat

The first side effect that many experience are meat cravings.

To make things worse, not eating something you’re used to might make you uncomfortable (“what do I eat instead?”), which can cause stress and anxiety.

Those make cravings even worse and it’s a self-repeating cycle.

I’ve written a full guide to vegan meat cravings and what to do about them.


When you stop eating meat, there’s a good chance that you will experience meat cravings.

Meat Withdrawal Symptoms

There are a variety of minor, but annoying possible meat withdrawal symptoms:

Meat withdrawal can cause some real physical side effects that aren’t just in your head.

Explanation: How Meat Withdrawal Symptoms Might Occur 

A B12 deficiency isn’t a concern since you likely have stores for at least a few months (if not years).

However, what is a concern is experiencing a Jarisch–Herxheimer reaction.

Here’s what a Herxheimer reaction consists of in simple terms:

  • Your gut bacteria consists of bacteria that specialize in breaking down certain foods.
  • Bacteria that specialize in digesting meat die off when you stop eating meat.
  • A Herxheimer reaction occurs when a large portion of bacteria die off at the same time.
  • These dead bacteria release their endotoxins into your blood faster than you can process them, causing a strong inflammatory response.

Note that this doesn’t happen right away. It takes days or weeks for a large portion of meat-eating bacteria to die. During this time you may experience the flu-like symptoms listed above.

While I’m just speculating, a reaction is probably more likely if you ate a diet heavy in red meat. White meat is more “plain” and easier to digest in general.

How Common Are Negative Side Effects of Not Eating Meat?

Symptoms don’t occur in everyone that stops eating meat. It depends on the amount of meat you ate before, resiliency of your body, and other factors.

For me, I had zero side effects, even though I went vegan cold turkey in the middle of a semi-professional soccer season. However, I didn’t eat a lot of meat before, and when I did it was usually white meat like chicken breast.

If you had a severe reaction (not common) you would need to see a doctor.

Otherwise, an anti-inflammatory like aspirin or ibuprofen should get you through any symptoms.

Not many people will experience the sort of reaction we went over above, but it is a possibility.


Most people won’t have a physical reaction when they stop eating meat. However, if you were a heavy meat eater, symptoms like headaches and fatigue are possible during this withdrawal period.

Potential Benefits From Not Eating Meat Anymore

The most common benefits that people report after they stop eating meat (or go vegan) are:

In the last few years, dozens of professional athletes have gone vegan across multiple sports (mostly the NFL and NBA).

These are some of the biggest, strongest athletes, and they often experience significant inflammation due to their size and sport demands.

So it means something when almost all of them have had nothing but positive things to say about their meat-free diet in terms of health effects.

SB Nation has a great collection of stories from these athletes, but let me highlight a few quotes from NBA players.

First, from Jahlil Okafor:

Cutting out dairy and the swelling went down and I went full fledge on it and I feel great.

Next, here’s what Kyrie Irving said:

So my energy is up, my body feels amazing. Just understanding what the diet is like for me and what’s beneficial for me for having the highest energy out here and being able to sustain it at a very high level

And finally, a quote from Damian Lillard:

I feel much better. I thought it was all hype. I thought people just said it just because it was a healthier food but I can feel it. I can definitely feel it.”


If you’ve struggled with issues like sluggishness or inflammation in the past, you might actually feel better shortly after giving up meat. This may happen right away, or after an initial transition period (i.e. you’ll feel worse before you feel better).

How Long Does it Take to “Detox” From Meat?

I hate the term detox just because it’s often surrounded by pseudoscience, but yes, there will be an adjustment period.

How long?

I can’t give you a great answer here, because there doesn’t seem to be any research about this specific topic.

What we can say from the research, is that it likely takes somewhere from a few days to a few weeks for bacteria to start to die off.

Here’s a quote from a researcher who looked at the growth of new bacteria when new food is introduced.

Within days we saw not just a variation in the abundance of different kinds of bacteria, but in the kinds of genes they were expressing.

Your gut reacts quickly to introducing new foods, but is probably a bit slower to discard unused bacteria.

Thinking about it logically, people often don’t eat a specific food for days or weeks, so it makes sense to try and keep around bacteria for those foods for a while, even if unused.

Again, no conclusive research behind that, just common sense, so it could be way off.


There’s no research-backed answer to how long meat withdrawal symptoms will take to pass. From common sense and what I’ve read from others, it usually takes anywhere from a few days to a few weeks depending on factors like prior meat consumption and personality.

Side Effects of Eating Meat After Being Vegan

Assuming the vast majority of your gut bacteria that can break down meat are gone (we’re talking months or years later), suddenly eating meat can give you issues.

When you first go vegan and start eating foods like beans that you’re not used to in fairly large amounts, it’s hard to digest. It causes bloating, gas, and other stomach issues.

Same goes for reintroducing meat. If you suddenly had a lot of it, you’ll have some big stomach issues. However, if you only had a small amount, it likely wouldn’t be too bad.


If you suddenly eat a significant amount of meat after not eating any meat for a while, it can cause you to get sick because your gut bacteria that is needed for processing meat is largely gone.

Summary of Meat Withdrawal

Meat withdrawal is a real thing that can cause both mental and physical side effects that mainly include cravings and flu-like symptoms.

However, once you’re through meat withdrawal, it’s fairly common to have more energy and less inflammation.

It likely takes weeks or months to fully adjust to a meat-free diet, and if you ever re-introduce meat to your diet, you should do it slowly.

Can You Die From Not Eating Meat?

This is a common question that I see.

The short answer is that you can be extremely healthy if you don’t eat meat, but you need to plan your diet.

Above all else, the most important nutrient that people get from meat is vitamin B12.

Vitamin B12 is crucial to nervous system function in many ways, and is difficult to get from plant foods. It’s a long story, but you can read more about vegan vitamin B12 sources here.

Getting a supplement is a good idea if you’ve gone entirely plant-based, and you should get your blood levels checked regularly by your doctor.

About the author

Dale Cudmore

Your friendly neighborhood vegan from Toronto. Chemical engineer turned semi-professional soccer player and freelance nutrition writer. I've been vegan for years and try to make life easier for others by sharing what I've learned.


  • I am on day 15 of no meat, and stopped cold turkey after eating it for thirty years. I have been extremely nauseous / dizzy and was very concerned for my health. It has been 4 days of feeling like this and the dizziness is starting to slowdown. I look forward to how I feel after all the bacteria dies off and my blood becomes crystal clean. 🤗 thank you very much for this article.

    • I hope you feel better. Consider seeing a doctor if you continue feeling unwell, the symptoms shouldn’t be that extreme, so there might be something else going on.

  • Thank you very much for the information it’s now 2 months of being a vegetarian but I’m still struggling not to eat egg what can I replace with

  • Sometimes I go a few days without it cause I don’t wish for it. I didn’t realize there would be side effects. I’m on day 4 and can’t sleep. I guess it was food poisoning from 2 days before quitting that made me quit. I actually feel calmer on days 3&4 but on day 2 I was emotional. Was hoping they would talk about urine as I may go see my doctor about that. I’m pretty thirsty despite drinking my usual amounts of liquids :-/

  • My husband, children and myself went cold turkey Whole Food/plant based 3 weeks ago. After 2 weeks I seemed to be the only one experiencing severe headaches, nausea, fatigue, insomnia, anxiety, mood swings, body aches. I felt so bad, Ibwas convinced that it was beyond detox and maybe I was deficient in something. My husband said he thought we just hadn’t done it long enough but suggested that maybe we should had fish in for now. I did feel a little better. But I still don’t have much of a taste for anything. Even when I’m hungry, I can’t really eat anything. I’m mad at myself for stepping backward with fish. What should I do at this point to move forward?

      • I’m going through the same thing as Stacey with one additional symptom. Breathing is shallow. Seem at certain times of the day my breathing is difficult. Been to the ER and all test say I’m great. But I have been experiencing this feeling since last Friday. I will add b12 back into my vitamin regimen. I stopped taking them a week ago as I thought they were delaying my weight loss.

  • Thank you for your insights and recommendations. Found it very truthful and useful. Dizziness, flu-like symptoms and some fatigue going and coming after maybe 4 weeks. Keep up your good work helping others. That’s what life is about ! Take care.

  • It’s my 3rd month. I’m also withdrawing from skin care products that I switched with natural products. Wow it’s tricky.

    It seems like every month since I started going alkaline I have a night or two where I have the shakes and anxiety and panic.

    Very strange it goes and comes back.
    Other than that a few minor symptoms but there is pain and darkness that comes with it for sure.

    You got to be strong and understand after years of eating meat and changing now your body is going through major change. Being kind to yourself and understanding this definitely helps the situation.

    Remember you’re not alone.

  • Great article, thank you!
    I began a vegetarian diet back in 2011 and then cold turkey vegan sometime in 2012/2013, and back to meat (I call it “flexitarian”) in 2015, and now vegetarian but hoping to slowly cut out dairy and bring in more fish if possible and if affordable where I am. Major things I noticed during all of this: 1. weight loss without trying between 2011 and 2017, 2. more bloating and stomach issues and overall feeling like a bloated balloon after going back to meat (and more processed foods with meat), and 3. this is more psychological I guess, but since my more heavier meat eating days in the last couple of years, I’ve had a craving for the way I felt as a vegetarian. I’ve come to think of this whole journey as a “I did this and tried that, and my conclusion: I don’t need meat to feel great inside and out”.
    I truly believe in eating what you want and what makes you feel great and healthy, and checking with a nutritionist or your doctor to make sure you are getting your nutrition needs met and that any health problems you notice are taken care of.