What are vegetarians not allowed to eat?

November 9, 2025 •

4 min read

According to a 2024 report, a vegetarian diet, by definition, excludes all meat, poultry, and fish. However, the question of what are vegetarians not allowed to eat extends far beyond just animal flesh, encompassing lesser-known ingredients derived from animal by-products and slaughter. Navigating this can be tricky, as many everyday foods contain surprising non-vegetarian additives.

Quick Summary

A vegetarian diet primarily excludes meat, poultry, and fish, but restrictions vary depending on the type of vegetarianism. Beyond the obvious, hidden animal-derived ingredients like gelatin, rennet, and certain food colorings must be avoided. This guide clarifies the specific limitations for different vegetarians and identifies common non-vegetarian additives.

Key Points

No Meat, Poultry, or Fish: The most basic rule is that vegetarians do not consume any animal flesh.
Hidden Animal By-products: Many processed foods contain hidden ingredients derived from animal parts, such as gelatin (from bones) and rennet (from calf stomach).
Variations in Diet: The rules can differ. Lacto-ovo vegetarians eat dairy and eggs, while vegans, the strictest, avoid all animal products, including honey and dairy.
Read Food Labels Carefully: Vigilance is key, as non-vegetarian additives like carmine (from insects) and certain 'natural flavorings' can be found in common foods.
Check for Vegetarian-Friendly Labels: Look for labels that explicitly state 'suitable for vegetarians' to avoid accidental consumption of non-vegetarian ingredients.

The Fundamental Rules of Vegetarianism

At its core, a vegetarian diet eliminates all forms of animal flesh, which includes red meat, poultry, and seafood. However, this simple rule has several interpretations, leading to different subcategories of vegetarianism with varying restrictions. For example, a lacto-ovo vegetarian includes dairy and eggs, while an ovo-vegetarian includes eggs but not dairy. The strictest form of vegetarianism is a vegan diet, which excludes all animal products and by-products. Regardless of the specific type, all vegetarians must be vigilant about avoiding certain foods and additives that contain animal-derived components.

Foods with Obvious Restrictions

This category includes the most straightforward and well-known forbidden foods. For all vegetarian types, these are universally avoided:

All red meat: This includes beef, pork, lamb, and game meats.
Poultry: Chicken, turkey, duck, and other fowl are not consumed.
Fish and Seafood: All types of fish, shellfish, and crustaceans like prawns and crab are excluded.
Broths and Stocks: Many soups and gravies are made with meat-based broths, so these must be avoided unless explicitly stated as vegetable-based.

Unexpected Hidden Animal Ingredients

This is where the diet can become complicated. Many processed foods, candies, and even baked goods contain non-vegetarian ingredients that are not immediately obvious. Careful label reading is essential for vegetarians to ensure their food is truly animal-free.

Gelatin: A protein derived from boiling the skin, tendons, ligaments, and bones of animals, often pigs and cows. It is used as a gelling agent in marshmallows, gummy candies, gel desserts, and some yogurts.
Rennet: An enzyme from the stomach lining of young calves, used in the production of many cheeses to curdle milk. Vegetarian cheeses use a non-animal-based microbial rennet instead.
Isinglass: A gelatin-like substance from the swim bladders of fish, used to clarify and filter some beers and wines.
Carmine (E120) and Cochineal: A red food coloring made from crushed cochineal insects. Found in some red-colored foods and beverages.
L-Cysteine: An amino acid that can be derived from animal sources like duck feathers or pig bristles, used as a dough conditioner in some commercially baked breads.
Natural Flavorings: The term "natural flavor" can be vague and may sometimes be derived from animal products, such as beef or chicken. Unless specified as vegan, a cautious vegetarian may need to investigate further.
Casein and Whey: These are milk proteins found in dairy products, but can also be used as additives in other foods, and are not suitable for vegans or lacto-vegetarians.

Comparison of Vegetarian Types and Their Restrictions

Navigating the world of vegetarianism means understanding the nuances between its different forms. The following table compares the main categories and their respective dietary inclusions and exclusions.


Food Item	Lacto-ovo Vegetarian	Lacto Vegetarian	Ovo Vegetarian	Vegan	Pescatarian (not strictly vegetarian)
Meat (Red, Poultry)	Excluded	Excluded	Excluded	Excluded	Excluded
Fish & Seafood	Excluded	Excluded	Excluded	Excluded	Included
Dairy (Milk, Cheese, Yogurt)	Included	Included	Excluded	Excluded	Included
Eggs	Included	Excluded	Included	Excluded	Included
Gelatin	Excluded	Excluded	Excluded	Excluded	Excluded
Honey	Included	Included	Included	Excluded	Included

Note: A pescatarian diet includes fish and is therefore not considered vegetarian by the Vegetarian Society.

Making Informed Choices as a Vegetarian

Becoming a vegetarian involves more than simply cutting out meat. It requires a mindful approach to food shopping and preparation. The best practice is to always read the ingredient list, especially for processed or packaged foods. Labels like "Suitable for Vegetarians" offer a good starting point, but knowing the hidden ingredients listed above is the ultimate way to ensure a truly animal-free diet. For dining out, it's wise to ask restaurant staff about the ingredients in dishes, particularly in soups, dressings, and desserts. A well-informed vegetarian can confidently enjoy a delicious and ethical diet without fear of accidental consumption of animal products. The Vegetarian Society provides useful resources for identifying vegetarian-friendly products and navigating labeling.

Conclusion

While the definition of what are vegetarians not allowed to eat begins with the obvious exclusion of meat, poultry, and fish, the full scope is much broader. Hidden animal-derived ingredients such as gelatin, rennet, and carmine are common culprits that can unknowingly find their way into a vegetarian's diet. Understanding the different types of vegetarianism and consistently reading food labels are the most effective strategies for maintaining an animal-free diet. With a little diligence, it's easy to uphold the principles of a vegetarian lifestyle while enjoying a wide variety of foods.

Optional Outbound Link

For more detailed information on common non-vegan and non-vegetarian ingredients, explore the database provided by Veganuary. https://veganuary.com/vegan-label-reading-guide/

Frequently Asked Questions

Gelatin is made by boiling the skin, tendons, ligaments, and bones of animals, primarily cows and pigs.

No, many cheeses are not vegetarian because they are made using animal rennet from the stomachs of calves. Always check the label to ensure it is made with microbial or vegetarian rennet.

It depends on the type of vegetarianism. Lacto-ovo vegetarians and ovo-vegetarians eat eggs, but lacto-vegetarians and vegans do not.

A vegetarian abstains from eating animal flesh (meat, poultry, fish), while a vegan avoids all animal products and by-products, including dairy, eggs, and honey.

Yes, most vegetarians consume honey, as it is a by-product of bees, but vegans do not, as they avoid all animal-derived products.

Carmine is a red food coloring derived from crushed cochineal insects. Yes, vegetarians should avoid it as it is an animal-derived product.

The best method is to carefully read the ingredients list on the packaging for any animal-derived ingredients or look for a 'Suitable for Vegetarians' label.