What Foods Does Lactase Break Down?

According to the National Institute of Diabetes and Digestive and Kidney Diseases, lactose malabsorption affects a significant portion of the global population. This condition, driven by insufficient lactase, directly impacts which foods does lactase break down and can cause a host of uncomfortable symptoms for many individuals.

Quick Summary

The lactase enzyme specifically breaks down lactose, the sugar found in milk and dairy products, into simpler sugars for absorption. People with lactose intolerance have insufficient lactase, leading to digestive issues when consuming these foods.

Key Points

• Lactase's Sole Purpose: The lactase enzyme is only responsible for breaking down lactose, the sugar found in milk and dairy products.

• Major Sources of Lactose: Primary foods that lactase breaks down include milk, yogurt, ice cream, soft cheeses, and whey.

• Hidden Lactose: Lactase is also needed to digest the lactose hidden in many processed foods, such as baked goods, cereals, instant mixes, and certain sauces.

• Variable Lactose Levels: Not all dairy is equal; aged hard cheeses and yogurt contain lower levels of lactose compared to liquid milk, due to processing.

• Lactose-Free Foods: Naturally lactose-free foods like fruits, vegetables, grains, and meats do not require lactase for digestion.

• Commercial Lactase: The food industry uses lactase to pre-digest lactose in milk, creating lactose-free products for consumers.

The Core Function of Lactase

Lactase is a crucial digestive enzyme produced in the small intestine, specifically by cells lining the brush border. Its primary and sole function is to break down lactose, a disaccharide sugar, into two simpler monosaccharides: glucose and galactose. This breakdown process is essential for the body to absorb and utilize these sugars for energy. Without sufficient lactase, lactose remains undigested and travels to the large intestine, where bacteria ferment it, leading to the gastrointestinal distress associated with lactose intolerance.

Dairy Products High in Lactose

Dairy products are the primary food source containing lactose, with varying concentrations. Those with higher liquid content generally have more lactose per serving. Lactase breaks down the lactose in these foods:

• Milk: All types of mammalian milk, including cow's, goat's, and sheep's, contain significant amounts of lactose. This includes whole, low-fat, and skim milk.
• Condensed and Evaporated Milk: These products have had most of their water removed, resulting in a highly concentrated lactose content.
• Ice Cream and Sherbet: The lactose content in these frozen desserts varies by brand and ingredients but is generally high.
• Soft Cheeses: Fresh, soft cheeses such as ricotta, cottage cheese, mascarpone, and cream cheese contain moderate to high levels of lactose.
• Processed Cheese: Some processed cheeses can contain milk solids or other lactose-containing ingredients, elevating their lactose level.
• Whey: This is a byproduct of cheese-making and is very high in lactose, especially whey protein concentrate.

Foods with Hidden Lactose

Lactose is not limited to obvious dairy items; it is a common additive in many processed foods. Reading ingredient labels is crucial for identifying hidden sources. Lactase will break down the lactose in these items if they contain milk derivatives:

• Baked Goods: Breads, pastries, cookies, and cakes often contain milk, buttermilk, or dry milk solids.
• Processed Cereals: Many breakfast cereals and instant oatmeal packets use milk solids in their manufacturing.
• Instant Mixes: Pancake, biscuit, instant potato, and soup mixes frequently contain lactose.
• Processed Meats: Some cold cuts, sausages, and hot dogs may contain milk solids as fillers or binders.
• Dressings and Sauces: Many creamy salad dressings, gravies, and cream-based sauces use milk derivatives.
• Chocolate and Confections: Milk chocolate contains lactose, and some candies and confections may as well.

Comparison of Lactose Content in Dairy Products

The lactose content in dairy products is not uniform and changes with processing and aging. This table provides a useful comparison:

Dairy Product	Lactose Content (Approx. per 100g)	Notes
Dried Milk Powder	~52.9g	Highly concentrated source.
Sweetened Condensed Milk	~12.3g	High concentration due to water removal.
Cow's Milk (Liquid)	~4.6-4.8g	Standard liquid milk, a primary source.
Yogurt (Plain)	~3.6-4.7g	Contains bacteria that pre-digest some lactose, making it more tolerable for some.
Cottage Cheese	~3.5g	Moderate lactose, may cause symptoms in sensitive individuals.
Feta Cheese	~1.4g	Moderate to low lactose content.
Cheddar Cheese (Aged)	<0.1g	The aging process significantly reduces lactose.
Butter	Trace amounts	Mostly milk fat, very low lactose.

Lactase's Role in Modern Food Production

Beyond natural digestion, lactase is used in the food industry to create lactose-free dairy products. In this process, commercial lactase enzymes are added to milk and other dairy goods to break down the lactose before it is consumed. This makes milk suitable for people with lactose intolerance, without sacrificing the nutritional benefits of dairy. The resulting milk has a slightly sweeter taste because glucose and galactose are sweeter than lactose.

Conclusion

In summary, the digestive enzyme lactase is specifically designed to break down lactose, a sugar found primarily in milk and dairy products. While its function seems straightforward, the presence of lactose in a vast array of processed and packaged foods means that managing a lactase deficiency requires diligence. By understanding which foods contain lactose—from the obvious dairy items to hidden sources in everyday processed goods—individuals with lactose intolerance can make informed dietary choices. For those seeking alternatives, lactase supplements and specially prepared lactose-free dairy products offer a way to enjoy the nutritional benefits of milk without the associated digestive discomfort.

For more information on digestive health, consult a medical professional or refer to resources from reputable organizations like the National Institutes of Health.

Frequently Asked Questions

Is lactose intolerance the same as a milk allergy?

No, lactose intolerance is a digestive issue caused by a lactase deficiency, while a milk allergy is an immune system reaction to the protein in milk.

Can people with lactose intolerance still eat cheese?

Yes, many people can tolerate small amounts of lactose. Hard cheeses like cheddar or Parmesan have very little lactose and are often well-tolerated, while soft cheeses like cottage cheese have more.

Are all milk products high in lactose?

No, the lactose content varies greatly. Liquid milk and condensed milk are high in lactose, while aged hard cheeses have very little. Yogurt also has less due to bacterial fermentation.

Does lactase break down other sugars?

No, lactase is a specific enzyme that only breaks down the disaccharide lactose into glucose and galactose. It does not act on other sugars like sucrose or fructose.

What is the difference between lactose-free milk and regular milk?

Lactose-free milk is regular milk that has had the lactase enzyme added to it. The enzyme breaks down the lactose into simpler sugars, making it easier to digest for those with a lactase deficiency.

How can I identify hidden lactose in packaged foods?

Look at the ingredient list on food labels for words such as milk, milk solids, whey, curds, milk powder, or nonfat dry milk.

Are lactase supplements effective?

Yes, over-the-counter lactase supplements can be taken before consuming dairy products to help with the digestion of lactose and prevent symptoms.