Understanding Digestion: Which foods have lactase enzyme?

October 5, 2025 •

4 min read

An estimated 65% of the world's population has a reduced ability to digest lactose after infancy, leading to lactose intolerance. Many people mistakenly search for specific foods to get the lactase enzyme, but the truth is that the human body is meant to produce this enzyme, and consuming certain foods can only support its activity rather than provide it directly.

Quick Summary

This article clarifies the difference between lactose and lactase, identifies foods like specific yogurts and kefir that contain beneficial lactase-producing bacteria, and explains how commercially prepared lactose-free products work. It also discusses the role of lactase supplements and probiotic options in managing lactose intolerance symptoms effectively.

Key Points

Lactase is not in food: The human body produces the lactase enzyme, not external food sources; foods can only contain bacteria that produce lactase.
Probiotics aid digestion: Fermented dairy, such as certain yogurts and kefir, contain live probiotic cultures that produce lactase, making these products more tolerable for many.
Lactose-free products use added lactase: Commercial lactose-free milk and dairy products have the lactase enzyme added during production to break down lactose.
Oral supplements are available: Over-the-counter lactase enzyme supplements (drops or tablets) can be taken with dairy to aid digestion.
Hard cheese is naturally low in lactose: Aged, hard cheeses like cheddar and parmesan contain very little lactose and are often well-tolerated.
Plant-based options are naturally lactose-free: Soy, almond, oat, and other plant-based milks do not contain lactose, offering a safe alternative.
Hidden lactose exists: Be vigilant for lactose in processed foods, baked goods, and condiments, as it can be a 'hidden' ingredient.

The Core Difference: Your Body Makes Lactase

Lactase is a digestive enzyme that your small intestine produces to break down lactose, the sugar found in milk. People with lactose intolerance do not produce enough lactase, meaning undigested lactose passes into the large intestine, where bacteria ferment it. This process creates gas and other byproducts that cause uncomfortable symptoms such as bloating, cramping, and diarrhea. The key takeaway is that you won't find the lactase enzyme itself in most foods. Instead, you can find foods that either contain bacteria that produce lactase or are fortified with the enzyme during processing.

Fermented Dairy: Your Probiotic Powerhouse

Fermented dairy products are the closest you will get to consuming a 'food with lactase enzyme,' as they contain live, active bacterial cultures (probiotics) that produce their own lactase. These bacteria aid in the digestion of lactose, making these products more tolerable for many people with lactose intolerance than regular milk.

Examples of Fermented Dairy Products:

Yogurt: Especially those with live and active cultures like Lactobacillus bulgaricus and Streptococcus thermophilus. The lactase is protected by the bacteria's cell walls and becomes active in the intestine. Plain yogurts with live cultures often contain less lactose than milk.
Kefir: This fermented milk drink is rich in various strains of probiotics, such as Lactobacillus acidophilus and Bifidobacterium lactis, which produce lactase and help break down lactose.
Aged/Hard Cheeses: During the aging process, the lactose in hard cheeses like cheddar, Swiss, and Parmesan is converted into lactic acid, resulting in a very low lactose content that is often well-tolerated.

Lactase-Treated and Fortified Foods

Food manufacturers create lactose-free products by adding the lactase enzyme during processing. This pre-digests the lactose, so the final product is suitable for people with lactose intolerance while retaining the nutritional benefits of dairy, like calcium and vitamin D.

Products with added lactase:

Lactose-Free Milk: Regular cow's milk that has been treated with the lactase enzyme. It tastes slightly sweeter due to the breakdown of lactose into simpler sugars.
Lactose-Free Ice Cream and Yogurt: These are made with milk that has undergone the same lactase treatment.

The Role of Probiotics and Supplements

For those seeking alternative ways to get digestive support, probiotic supplements containing lactase-producing bacterial strains can be a valuable tool. Taking a daily probiotic supplement may help balance gut flora and alleviate symptoms. Another option is oral lactase supplements, which can be taken immediately before a meal containing dairy to help digest the lactose.

Foods That Do Not Contain Lactase

It is crucial to differentiate between foods that help digest lactose and those that contain no lactose at all. Many people with severe intolerance turn to naturally lactose-free alternatives.

Naturally Lactose-Free Food Examples:

Plant-Based Milks: Options like soy, almond, oat, and coconut milk contain no lactose and are suitable substitutes for traditional dairy. Always check for added calcium to ensure a comparable nutritional profile.
Fruits and Vegetables: All fruits and vegetables are naturally lactose-free.
Meat, Poultry, and Seafood: These foods do not contain lactose.
Eggs: Despite being found in the dairy section, eggs are not dairy products and are lactose-free.

Comparison of Dairy Product Types for Lactose-Intolerant Individuals


Feature	Regular Dairy (Milk, Ice Cream)	Fermented Dairy (Yogurt, Kefir)	Lactose-Free Dairy	Plant-Based Alternatives	Lactase Supplements
Lactase Source	None	Live bacterial cultures (probiotics)	Added during processing	None	Pill/drop containing lactase enzyme
Mechanism	The body's own lactase is required for digestion.	Bacteria produce lactase, aiding digestion of lactose in the product.	Enzyme has already broken down lactose.	No lactose present, so no lactase is needed.	Enzyme is taken orally to aid digestion of other food.
Lactose Content	High	Lower than regular milk; varies by type	Very Low to None	None	Can help with digestion of lactose.
Tolerance for Intolerant Individuals	Poor, causes symptoms	Generally well-tolerated, especially with live cultures	Excellent, designed for intolerance	Excellent, naturally lactose-free	Helps improve tolerance
Nutritional Profile	High in calcium and protein	Good source of calcium, protein, and probiotics	Same as regular dairy but with pre-digested lactose	Varies; check for fortified calcium and vitamins	N/A (supplement)

Conclusion: Navigating Lactose Intolerance with Informed Choices

While no food naturally contains the human lactase enzyme, those managing lactose intolerance have several effective strategies available. Fermented dairy products like kefir and yogurt offer a source of lactase-producing probiotics that can significantly aid digestion. Commercially prepared lactose-free dairy items provide a reliable alternative, having been treated with the enzyme during manufacturing. For those consuming dairy that has not been treated, over-the-counter lactase supplements offer a convenient way to get the necessary enzyme boost. By understanding these distinctions, individuals can make informed dietary choices that help them enjoy a wider variety of foods without discomfort. Consulting a healthcare provider or a dietitian is always recommended to tailor a diet plan that meets individual needs and nutritional requirements. For further reading on dietary adjustments, the National Institute of Diabetes and Digestive and Kidney Diseases provides comprehensive information on eating with lactose intolerance.

Frequently Asked Questions

No, fruits do not contain the lactase enzyme, as it is produced in the small intestine of mammals to digest milk sugar. All fruits are naturally lactose-free.

Not all, but yogurts labeled with 'live and active cultures' contain bacteria that produce lactase, which can aid in the digestion of the yogurt's lactose content. Heated or pasteurized yogurts may not have these live cultures.

Lactase supplements provide the enzyme to aid digestion, but their effectiveness can vary between individuals and depending on the dose and specific formulation. Natural sources, like the probiotics in fermented dairy, work within the gut to produce their own lactase.

Read the ingredients list carefully for terms such as milk, lactose, whey, curds, milk solids, or milk powder, which all indicate the presence of lactose.

No, the body's natural lactase production is genetically determined and typically decreases after infancy. While you cannot increase your body's own production, you can introduce lactase through supplements or lactase-producing probiotics.

Yes, you can add lactase drops to regular milk and store it in the refrigerator. The enzyme will break down the lactose over time, making it suitable for those with lactose intolerance.

Lactose intolerance is a digestive issue caused by a lack of the lactase enzyme, while a milk allergy is an immune system response to milk proteins (casein or whey). Lactose-free products are not suitable for people with a milk allergy.