What Happens if I Eat Meat After Being Vegan? An Overview

October 7, 2025 •

4 min read

According to some studies, over 80% of people who try veganism or vegetarianism eventually return to eating meat. If you're contemplating this transition, it's natural to wonder, what happens if I eat meat after being vegan? The physical and psychological effects vary, but understanding them can help you prepare for a smoother dietary shift.

Quick Summary

A transition from veganism to eating meat can cause temporary digestive discomfort as your body adjusts its gut flora and enzyme production, but serious illness is unlikely.

Key Points

Initial Digestive Issues: Temporary bloating, gas, constipation, or diarrhea are common as your gut biome and enzymes adjust to digesting meat again.
Body Retains Digestive Ability: Your body does not lose the ability to digest meat, but enzyme production may need time to ramp back up after a long period of veganism.
Start Slowly and Gradually: To minimize discomfort, begin with small portions of easily digestible meats like fish, eggs, or chicken broth before introducing red meat.
Emotional Responses are Normal: Feelings of guilt or emotional distress, especially if your veganism was ethically motivated, are common and can be addressed with support.
Potential Nutrient Benefits: Reintroducing meat can boost nutrient levels, particularly iron and vitamin B12, which may lead to increased energy.
Maintain Fiber Intake: Continue to include plenty of fiber from plant foods to support gut health and aid digestion during the transition.
Listen to Your Body: Pay attention to how different types and portions of meat affect you and adjust your pace accordingly.

The Initial Physical Reactions: What to Expect

Reintroducing meat after a period of veganism can cause a range of temporary physical symptoms as your body's digestive system, which has adapted to a plant-based diet, works to process a new type of food. For most people, these symptoms are mild and short-lived.

The Gut Microbiome Shift

Over time, a vegan diet fosters a gut microbiome rich in bacteria that are efficient at breaking down plant fibers. When you reintroduce meat, which is high in protein and fat, this community of microbes needs to change. The balance of gut bacteria shifts, which can lead to initial digestive disturbances.

Bloating and Gas: The introduction of dense proteins and fats that your gut isn't accustomed to can cause fermentation and gas, leading to bloating and discomfort.
Constipation or Diarrhea: Meat is low in fiber compared to most plant foods. This decrease in fiber intake, combined with the extra time needed to digest meat, can cause temporary constipation. Conversely, some individuals may experience diarrhea as their system reacts to the unfamiliar proteins and fats.

Enzymes and Digestion

While your body doesn't completely lose its ability to digest meat, the levels of meat-specific digestive enzymes, particularly proteases, may decrease during a prolonged vegan diet. When meat is reintroduced, it can take time for enzyme production to ramp back up. This can result in the meat sitting in the gut longer, potentially causing nausea or a feeling of heaviness. Starting with smaller portions of easier-to-digest meats can help mitigate this.

The Psychological and Emotional Aspects

The transition can be mentally and emotionally challenging, especially if your veganism was motivated by ethical or environmental concerns.

Feelings of Guilt: Many ex-vegans report feeling guilty or emotionally distressed after eating meat again. This is a normal and valid response rooted in compassion and empathy. Finding support from communities of former vegans or consulting a dietitian can be helpful.
Anxiety and Stress: Anxiety related to the change can sometimes manifest as physical symptoms, like heartburn or indigestion, blurring the lines between physiological and psychological reactions.

Navigating the Transition: A Guide to Reintroducing Meat

A gradual approach is key to minimizing discomfort and allowing your body time to adapt.

A Step-by-Step Reintroduction Plan

Start with bone broth or eggs: These are gentle on the digestive system and can ease your body back into processing animal products.
Move to fish and poultry: Lighter meats like salmon or chicken are easier to digest than red meat. Begin with small portions, around 2-3 ounces.
Increase slowly: As your body adapts, gradually increase the portion size and frequency. Listen to your body's signals and don't rush the process.
Balance your plate: Continue to include plenty of fiber-rich fruits, vegetables, and whole grains to maintain a healthy gut and aid digestion.
Stay hydrated: Drink plenty of water to support your body's digestive processes.

Comparative Table: Initial Vegan to Omnivore Transition


Aspect	Sudden Reintroduction	Gradual Reintroduction
Digestive Symptoms	Higher risk of severe bloating, gas, stomach cramps, and irregular bowel movements.	Milder and shorter-lived digestive symptoms.
Psychological Impact	Increased potential for shock, guilt, and emotional distress.	Allows time for mental and emotional adjustment, reducing guilt.
Adjustment Period	Can cause prolonged discomfort as the body is overwhelmed.	Smoother, more controlled adjustment for the digestive system and gut flora.
Nutrient Balance	May cause an imbalance as the body adjusts to new nutrient sources.	Easier to maintain a balanced diet by slowly incorporating new nutrient sources.
Satiety	Could feel heavy and overfull initially due to dense protein and fat.	Allows the body to adjust to feeling full on different food types.

Potential Health Benefits and Drawbacks

For some, reintroducing meat can bring notable health benefits, particularly if they had developed nutritional deficiencies on their vegan diet.

Increased Energy: Meat is a rich source of iron and vitamin B12, and its reintroduction can lead to increased energy levels, especially for those who were previously deficient.
Improved Body Composition: Meat provides complete protein, which can support muscle building and satiety.

However, it's also important to be mindful of potential drawbacks, such as the increased saturated fat and cholesterol in certain meat types. Choosing lean, high-quality, and sustainably sourced options can help mitigate these concerns.

Conclusion: Making an Informed Choice

Deciding to reintroduce meat after a period of veganism is a personal choice with both physical and emotional considerations. While temporary digestive upset is likely as your body and gut microbiome adjust, your digestive system has not forgotten how to process meat. The key to a smooth transition lies in a gradual, mindful approach, starting with small portions of lighter meats. Understanding the potential for temporary discomfort, both physical and psychological, can help you navigate this change with patience and self-compassion. For personalized guidance, consulting a registered dietitian is always a prudent step. Ultimately, the goal is to find a dietary pattern that best supports your individual health and well-being.

Expert Recommendations and Support

Finding the right support during this transition can make a significant difference. Consulting a healthcare professional or a registered dietitian is highly recommended to ensure you address any nutritional needs and concerns. They can help you create a personalized plan that minimizes discomfort and maximizes health benefits. For those with ethical concerns, choosing responsibly sourced, pasture-raised meats can provide a middle ground. Remember, your health and wellness are the priority, and there is no single right answer for everyone. Support from friends, family, or online communities of former vegans can also provide valuable emotional support and shared experiences during this change. For some, maintaining a flexitarian approach—integrating meat on occasion—can be a sustainable and satisfying option.

Frequently Asked Questions

It is highly unlikely you will become seriously ill from reintroducing meat. While digestive upset like bloating or gas is common, it is almost always temporary.

No, your body does not lose the ability to digest meat. However, your gut flora and levels of specific digestive enzymes may need time to readapt and increase their function to process animal products efficiently.

A gradual approach is recommended. Start with small, manageable portions of easily digestible meats like fish, chicken, or bone broth before moving on to red meats. Pair meat with plenty of fiber-rich vegetables.

Feelings of guilt are common, especially for those with ethical motivations. Focus on your reasons for the change, prioritize your health, and consider discussing your feelings with a registered dietitian or finding a supportive community of ex-vegans.

For some individuals, especially those with low levels of iron or vitamin B12, reintroducing meat can lead to increased energy and a feeling of greater satiety due to the high-quality protein and nutrient density.

The duration of digestive discomfort varies, but for most people, initial symptoms resolve within a few days or weeks as the digestive system adapts. Going slowly and listening to your body's cues helps minimize the severity.

Starting with leaner cuts of meat like fish or chicken is often easier on the digestive system, which may be unaccustomed to processing high levels of animal fat. Some individuals may find fattier fish like salmon to be a good starting point, as they also offer beneficial omega-3s.