Can Lacto-Ovo Vegetarians Eat Cheese?

December 8, 2025 •

3 min read

While lacto-ovo vegetarianism includes dairy products, the truth is that not all cheese is suitable for this diet. The determining factor lies in how the cheese is made, specifically the type of milk-clotting enzyme, or rennet, that is used.

Quick Summary

The suitability of cheese for lacto-ovo vegetarians depends on the type of rennet used in its production. Traditional cheeses use animal rennet, while vegetarian-friendly options are made with microbial, plant-based, or fermentation-produced chymosin. Checking labels and product information is crucial for informed choices.

Key Points

Rennet is the deciding factor: The enzyme rennet, used to coagulate milk, is the key determinant for whether a cheese is vegetarian. Animal-derived rennet from calf stomachs makes cheese non-vegetarian.
Most factory cheese is vegetarian: The majority of commercially produced cheese, especially in the US and Europe, uses microbial rennet or fermentation-produced chymosin (FPC), which are vegetarian.
Check the label for clarity: Look for phrases like "microbial enzymes," "vegetarian rennet," or certifications like the V-label to confirm if a cheese is suitable for a lacto-ovo diet.
Soft cheeses are generally safe: Many soft cheeses, such as ricotta, paneer, and cottage cheese, are coagulated with acid instead of rennet, making them reliably vegetarian.
Beware of traditional hard cheeses: Authentic, protected-designation hard cheeses like Parmigiano-Reggiano and Gorgonzola are legally required to use animal rennet and are therefore not vegetarian.
Look for vegetarian alternatives: For traditionally non-vegetarian cheeses like Parmesan, many brands offer specific vegetarian versions made with non-animal rennet.

The Core Issue: Understanding Rennet

Rennet is a complex of enzymes that plays a critical role in cheesemaking by coagulating milk, separating it into solid curds and liquid whey. Historically, rennet was sourced from the stomachs of young, unweaned calves, lambs, or kids, making cheeses made with this animal-derived coagulant unsuitable for vegetarians. However, the modern food industry offers several vegetarian-friendly rennet alternatives, and the vast majority of factory-produced cheese today is made with non-animal versions.

Types of Rennet and Their Sources

Animal Rennet: Extracted from the stomach lining of young ruminant animals, animal rennet contains the enzyme chymosin and is a byproduct of the meat industry. Cheeses made with this traditional method are not vegetarian.
Microbial Rennet: This vegetarian alternative is produced by cultivating specific molds, such as Rhizomucor miehei, and is widely used for many cheese types, especially soft and young cheeses.
Plant-Based Rennet: Derived from plants like cardoon thistle, artichoke, or nettles, this coagulant is used in some artisanal or specific regional cheeses, particularly in Spain and Portugal.
Fermentation-Produced Chymosin (FPC): Created through genetic engineering, FPC is a genetically identical version of the enzyme found in animal stomachs, but is produced in a lab using microorganisms. This is the most common rennet used in commercial cheese production today and is considered vegetarian.

How to Determine if a Cheese is Vegetarian

Identifying a cheese's rennet source is the key to making a vegetarian-friendly choice. Unfortunately, not all labels are explicit. The best course of action is to check the packaging carefully and look for specific indicators.

Decoding the Label

Read the Ingredients: Check the label for phrases like "microbial enzymes," "vegetarian enzymes," or "plant-based rennet". If the label only lists "enzymes" or "rennet" without further clarification, it's safer to assume it's animal-derived.
Look for Certifications: The Vegetarian Society or similar organizations use symbols like the 'V' label to indicate products certified as suitable for vegetarians. This is the most straightforward way to confirm.
Be Aware of Traditional Cheeses: Some traditional cheeses, especially those with Protected Designation of Origin (PDO) status, must legally use animal rennet to be authentic. Examples include genuine Parmigiano-Reggiano and Gorgonzola.

A Note on Soft Cheeses

Some soft cheeses, such as paneer, cottage cheese, and fresh ricotta, do not rely on rennet for coagulation at all. They are typically set using an acid, like lemon juice or vinegar, and are therefore always vegetarian-friendly.

Navigating the Cheese Aisle: Common Cheeses


Cheese Type	Traditional Preparation	Is it Vegetarian?	How to Verify
Cheddar	Often made with animal rennet, especially traditional artisan versions.	Sometimes	Many mass-produced versions are vegetarian. Check for "microbial enzymes" or the V-label.
Parmesan	True Parmigiano-Reggiano legally requires animal rennet.	No	Any authentic Parmesan is not vegetarian. Look for domestic or store-brand "vegetarian parmesan" alternatives.
Mozzarella	Traditional European versions may use animal rennet.	Sometimes	Most widely available fresh mozzarella uses microbial rennet and is vegetarian. Always check the label.
Feta	Traditional feta often uses animal rennet.	Sometimes	Many modern producers use microbial rennet for vegetarian-friendly feta. Label confirmation is essential.
Swiss (Emmental)	Can vary; some traditional versions use animal rennet.	Sometimes	Many mild or mass-produced Swiss cheeses are vegetarian. Look for specific rennet labeling.
Blue Cheese	Some European blue cheeses like Gorgonzola and Roquefort are not vegetarian.	Sometimes	Stilton is typically vegetarian. Read the label or look for a vegetarian mark for others.
Goat Cheese	Traditional French versions may use animal rennet.	Sometimes	British and modern goat cheeses are often vegetarian. Check the label to be sure.
Ricotta & Paneer	Traditionally coagulated with acid rather than rennet.	Always	These soft cheeses are reliably vegetarian.

Conclusion

In summary, while lacto-ovo vegetarians include dairy in their diet, the assumption that all cheese is safe for consumption is incorrect. The presence of animal-derived rennet in many traditional hard cheeses makes them off-limits for strict followers of the diet. However, the rise of microbial and plant-based rennets means that a wide variety of delicious and accessible vegetarian-friendly cheeses are available today. By diligently checking ingredient lists, looking for vegetarian certification labels, and understanding which cheeses are traditionally made with animal rennet, lacto-ovo vegetarians can confidently navigate the cheese aisle and continue to enjoy this beloved food.

This guide offers general information based on common manufacturing practices. It is always recommended to check individual product labels and, when in doubt, contact the manufacturer.

Frequently Asked Questions

Rennet is a complex of enzymes used to curdle milk during cheesemaking. Traditional rennet is derived from the stomach lining of young animals, making it unsuitable for vegetarians. Modern alternatives, like microbial or plant-based rennet, are used for vegetarian-friendly cheeses.

Yes, most soft cheeses, including cream cheese, cottage cheese, and ricotta, are typically coagulated with acid (like vinegar or lemon juice) instead of rennet, making them safe for lacto-ovo vegetarians.

No, by Italian law, authentic Parmigiano-Reggiano must be made with animal rennet. Vegetarians should look for domestic or store-brand versions of 'vegetarian parmesan' that use microbial rennet.

A vegetarian label, such as the V-label, certifies that the product does not contain any animal-derived ingredients, including animal rennet. This is the most reliable indicator for vegetarians.

If the label only lists "enzymes" or "rennet" without specifying the source, it's a strong indicator that animal rennet was used, especially for traditional hard cheeses. For clarification, contact the manufacturer or opt for products explicitly labeled as vegetarian.

Some blue cheeses are vegetarian, while others are not. Traditional Gorgonzola and Roquefort typically use animal rennet. However, Stilton is reliably vegetarian, and other brands offer microbial rennet versions. Always check the label.

Many mass-produced cheddars, mozzarella, and Swiss cheeses are vegetarian. Options like paneer, ricotta, cottage cheese, and Stilton are also excellent choices. Always confirm the specific product's rennet source.