What do vegetarians cannot eat? A complete guide to the meat-free diet

December 13, 2025 •

4 min read

According to a 2019 Gallup poll, 5% of the US population identifies as vegetarian. This growing trend often leads to the question: what do vegetarians cannot eat? The answer is more complex than just avoiding meat, involving a careful look at a wide range of ingredients and personal dietary choices.

Quick Summary

A vegetarian diet excludes animal flesh, poultry, fish, and seafood. Specific exclusions for dairy and eggs vary depending on the dietary subtype, with hidden animal ingredients like gelatin often being avoided across the board.

Key Points

Strict Exclusions: A vegetarian diet forbids all types of animal flesh, including meat, poultry, fish, and seafood.
Hidden Ingredients: Animal by-products like gelatin, animal rennet in cheese, and carmine are often hidden in processed foods and must be avoided.
Diverse Diets: Different types of vegetarians exist; lacto-ovo vegetarians eat dairy and eggs, lacto-vegetarians eat dairy but no eggs, and ovo-vegetarians eat eggs but no dairy.
Label Literacy: Careful reading of ingredient lists is essential to identify hidden animal ingredients, particularly in processed foods and condiments.
Nutrient Planning: While a well-planned vegetarian diet is healthy, special attention to nutrients like Vitamin B12, iron, and calcium is often necessary to ensure a balanced intake.
Vegan Distinction: A vegan diet is stricter than vegetarianism, excluding all animal-derived products, including dairy, eggs, and honey.

The Absolute Non-Negotiables: Meat and Animal Flesh

At its core, a vegetarian diet strictly prohibits the consumption of animal flesh. This includes a broad spectrum of foods from various sources.

Meats

Beef
Pork (including bacon, ham, and sausages)
Lamb
Veal

Poultry

Chicken
Turkey
Duck
Goose

Seafood

Fish (e.g., tuna, salmon, cod)
Shellfish (e.g., shrimp, crab, lobster)
Mollusks (e.g., clams, mussels)

A Closer Look at Hidden Animal Ingredients

For many vegetarians, especially those conscious of animal welfare, the diet extends beyond just visible meat. Many processed foods contain animal-derived ingredients that are not immediately obvious. Careful label-reading is essential.

Gelatin: A common thickening agent in gummies, marshmallows, and some yogurts, gelatin is made from boiled animal parts, including skin, bones, and tendons.
Rennet: Used to coagulate milk in cheesemaking, rennet traditionally comes from the stomachs of calves. Many cheeses, particularly traditional ones like Parmigiano Reggiano, are therefore not vegetarian. Vegetarian-friendly cheeses use microbial or vegetable-based rennet.
Carmine: This red food coloring is derived from crushed cochineal insects and can be found in a variety of foods and cosmetics.
Lard: Rendered pig fat, used in some baked goods and snacks for texture.
Isinglass: Derived from fish bladders, this is used as a clarifying agent in some beers and wines.
Natural Flavors: This term can be ambiguous and, unless certified vegan, may include animal-derived components like meat extracts or dairy products.

Different Shades of Vegetarianism

Not all vegetarian diets are identical. The inclusion or exclusion of eggs and dairy products is a key differentiator, creating distinct types of vegetarianism.

Ovo-Vegetarianism

This diet excludes meat, poultry, and fish, but includes eggs. It excludes dairy products.

Lacto-Vegetarianism

This diet excludes meat, poultry, fish, and eggs, but includes dairy products like milk, cheese, and yogurt.

Lacto-Ovo Vegetarianism

This is the most common type in the Western world and excludes meat, poultry, and fish while permitting both eggs and dairy products.

Veganism

Often confused with vegetarianism, a vegan diet is the strictest form of plant-based eating, excluding all animal products and by-products, including meat, fish, poultry, dairy, eggs, and often honey.

Comparing Vegetarian Diets: What's Included?


Diet Type	Meat, Poultry, Fish	Dairy	Eggs	Key Exclusion
Lacto-ovo-vegetarian	No	Yes	Yes	All animal flesh
Lacto-vegetarian	No	Yes	No	All animal flesh and eggs
Ovo-vegetarian	No	No	Yes	All animal flesh and dairy
Vegan	No	No	No	All animal-derived products

Navigating the Supermarket: Tips for Identifying Non-Vegetarian Foods

To ensure adherence to a vegetarian diet, it's crucial to know how to spot non-vegetarian ingredients, especially in processed goods. Here's a practical checklist:

Read ingredient lists thoroughly: Don't just rely on the name of the product. Look at the full list for any hidden animal products mentioned above.
Look for certification labels: Look for a reputable vegetarian or vegan certification symbol on the packaging, which confirms the product is free from animal-derived ingredients.
Be wary of vague terms: Phrases like “natural flavors” can be a red flag. If in doubt, contact the manufacturer or avoid the product.
Check the 'contains' statement: The allergy statement often lists common allergens like milk and eggs, which can help lacto- and ovo-vegetarians, respectively.
Research traditional products: For items like cheese, know that some traditional varieties legally require animal rennet, so vegetarian alternatives should be sought.

Nutritional Considerations for a Vegetarian Diet

For many, planning a well-balanced vegetarian diet is a priority. While it is possible to get all necessary nutrients, certain vitamins and minerals need careful attention, especially when removing certain food groups. A balanced diet should include a wide variety of foods from the five food groups.

Protein: Vegetarians can get ample protein from sources like legumes, nuts, seeds, tofu, and other soy products.
Iron: Non-haem iron from plant sources is less easily absorbed than haem iron from meat. Pairing iron-rich plant foods like lentils and spinach with Vitamin C sources (e.g., citrus fruits) can aid absorption.
Calcium: For those avoiding dairy, calcium can be obtained from fortified plant-based milks, tofu, and leafy greens.
Vitamin B12: This vitamin is found almost exclusively in animal products. Vegans and some strict vegetarians may need to rely on fortified foods (like certain cereals or nutritional yeast) or supplements.

A well-planned vegetarian diet is suitable for all stages of life and can provide numerous health benefits, including a reduced risk of chronic diseases. For more information on creating a healthy, balanced vegetarian diet, see the MedlinePlus Medical Encyclopedia.

Conclusion: Making Informed Choices

Understanding what do vegetarians cannot eat involves more than a simple list of prohibited meats. It's a nuanced approach that considers different diet variations, hidden ingredients, and individual ethical or health-related choices. By learning to navigate food labels and becoming aware of common animal-derived components, anyone can confidently maintain a vegetarian lifestyle. The key is knowledge and making informed decisions that align with one's personal dietary values.

Frequently Asked Questions

The main food group that vegetarians do not eat is animal flesh, which includes all types of meat, poultry, fish, and seafood.

Some vegetarians eat eggs, and others do not. This depends on their specific diet subtype. For example, lacto-ovo vegetarians eat eggs, while lacto-vegetarians do not.

No, not all cheese is vegetarian. Many traditional cheeses are made with animal rennet, an enzyme from a calf's stomach. Vegetarians must seek out cheeses made with microbial or vegetable rennet.

A vegetarian avoids animal flesh but may consume animal products like dairy and eggs, depending on their subtype. A vegan, however, avoids all animal-derived products, including dairy, eggs, and honey.

No, vegetarians do not eat fish. A diet that includes fish but not other meat is called a pescatarian diet, which is a different category of eating.

Some common hidden animal ingredients include gelatin (in marshmallows and some desserts), animal rennet (in some cheeses), carmine (a red dye), and certain 'natural flavors'.

The main types are lacto-ovo-vegetarians (eat dairy and eggs), lacto-vegetarians (eat dairy, no eggs), ovo-vegetarians (eat eggs, no dairy), and vegans (no animal products at all).

Animal rennet is a mixture of enzymes harvested from the stomach of calves. It is not vegetarian because its production involves the killing of an animal.