Lactose intolerance is a common digestive condition that affects millions of people worldwide. It occurs when the body cannot properly digest lactose, the natural sugar found in milk and other dairy products. In this blog post, I will delve into the science of lactose intolerance, its symptoms, causes and management strategies.
READ MORE: Explore the internet’s most extensive lactose in cheese database →
What is lactose intolerance?
Lactose is a disaccharide sugar composed of glucose and galactose, which are typically broken down in the small intestine by an enzyme called lactase. In people with lactose intolerance, there is a deficiency of lactase, leading to the incomplete digestion of lactose. As a result, lactose passes undigested into the colon, where it is fermented by bacteria. This causes symptoms like gas, bloating, diarrhoea and abdominal pain.
Types of lactose intolerance
- Primary Lactose Intolerance: This is the most common form and is genetically determined. In many people, lactase production decreases with age. This decline is more prevalent in certain populations, particularly among East Asian, West African, Arab, Jewish, Greek and Italian descent. In those populations, up to 90% of adults may be affected.
- Secondary Lactose Intolerance: This form results from an injury or illness that affects the small intestine, such as Crohn’s disease, coeliac disease or severe gastroenteritis. In these cases, the condition may be temporary and improve once the underlying issue is resolved.
- Congenital Lactase Deficiency: This rare condition is present from birth, due to a genetic mutation that prevents the production of lactase. Infants with this condition cannot tolerate lactose in breast milk or formula.
- Developmental Lactose Intolerance: Premature infants may experience lactose intolerance temporarily due to the immaturity of their digestive system. This usually resolves as they grow.
Symptoms of lactose intolerance
The symptoms of lactose intolerance can range from mild to severe and typically appear 30 minutes to two hours after consuming lactose-containing foods. Common symptoms include:
- Abdominal pain and cramps
- Bloating and gas
- Diarrhoea
- Nausea, sometimes with vomiting
- Rumbling or growling stomach
These symptoms are caused by the fermentation of undigested lactose in the colon, leading to the production of gases like hydrogen, methane and carbon dioxide.
Diagnosing lactose intolerance
If you suspect you have lactose intolerance, it’s important to get a proper diagnosis. Self-diagnosis can lead to unnecessary dietary restrictions and nutritional deficiencies. The following tests are commonly used to diagnose lactose intolerance:
- Lactose Tolerance Test: After fasting, the patient drinks a lactose-containing liquid, and blood samples are taken over a few hours to measure glucose levels. A lack of increase in blood glucose suggests lactose intolerance.
- Hydrogen Breath Test: This test measures the amount of hydrogen in the breath after consuming a lactose-containing beverage. High levels of hydrogen indicate improper digestion of lactose.
- Stool Acidity Test: Mainly used for infants and young children, this test measures the lactic acid in stool, which is produced when undigested lactose ferments in the colon.
Management strategies for lactose intolerance
Managing this food intolerance involves dietary adjustments to reduce or eliminate lactose while ensuring adequate nutrition. Here are some strategies to help manage the condition:
- Lactose-Free and Low-Lactose Dairy Products: Many lactose-free milk and dairy products are available on the market. These products contain the same nutrients as regular dairy but without the lactose.
- Lactase Supplements: Over-the-counter lactase enzyme supplements can help digest lactose. Taking these with meals can allow individuals to consume small amounts of lactose without experiencing symptoms.
- Gradual Reintroduction: Some individuals can tolerate small amounts of lactose if introduced gradually. Start with small servings and increase slowly to find your tolerance level.
- Alternative Sources of Calcium and Vitamin D: If dairy is significantly restricted, it’s important to find other sources of calcium and vitamin D, such as fortified plant-based milks, leafy greens, almonds and fish.
- Probiotics: Probiotics can sometimes help improve lactose digestion, as some strains of beneficial bacteria produce lactase, aiding in the breakdown of lactose.
Consuming dairy when intolerant to lactose
For many, dairy products are a significant part of their diet, providing essential nutrients like calcium, vitamin D, and protein. The thought of having to give up dairy due to lactose intolerance can be daunting.. But with the right approach, it’s often possible to continue enjoying many dairy products, including cheese.
Which cheeses can you eat?
Cheese is a diverse category with varying levels of lactose content. Generally, the longer the cheese is aged, the lower its lactose content. During the fermentation process, bacteria convert lactose into lactic acid, significantly reducing the lactose content. Here’s a breakdown of different types of cheese and their suitability for lactose-intolerant individuals:
- Hard Cheeses: Cheeses like Parmesan, Cheddar, Gruyère and Gouda are aged for longer periods, resulting in very low lactose content. These cheeses often contain less than 0.1 grams of lactose per serving and are typically well-tolerated.
- Semi-Hard and Semi-Soft Cheeses: Cheeses such as Mozzarella, Provolone and Feta have slightly higher lactose content but are still relatively low. They may be tolerated in moderate amounts depending on individual sensitivity.
- Soft Cheeses: Cheeses like Brie and Camembert have higher lactose content and may cause symptoms in lactose-intolerant individuals. However, lactose-free versions of these cheeses are increasingly available.
- Fresh Cheeses: Fresh cheeses like Queso Fresco and Paneer have the highest lactose content and are often not tolerated by those with lactose intolerance.
You can read more about which types of cheese are lactose free in this dedicated post here.
Choosing lactose-free cheeses
Many cheese manufacturers now produce lactose-free versions of popular cheeses. These products are made by adding lactase enzyme to the cheese during production, breaking down the lactose into glucose and galactose. This process makes the cheese easier to digest without altering its flavour or texture significantly.
When choosing lactose-free cheese, look for labels that specifically state “lactose-free.” These products are ideal for those who are highly sensitive to even small amounts of lactose.
Dairy alternatives for the lactose-intolerant
For those who cannot tolerate dairy at all, there are many non-dairy alternatives available that provide similar taste and nutritional benefits:
- Plant-Based Milks: Options like almond milk, soy milk, oat milk and coconut milk are widely available. Many are fortified with calcium, vitamin D and other nutrients.
- Non-Dairy Yoghurts: Made from plant-based milks, these yogurts are often fortified and available in various flavours.
- Plant-Based Cheese: Vegan cheeses, made from nuts, soy or starch, have improved significantly in taste and texture. They come in a variety of styles, from soft spreads to hard blocks.
- Non-Dairy Creamers and Butters: These alternatives are made from plant oils and offer similar functionality to dairy creamers and butters.
Nutritional considerations for lactose-intolerant people
Eliminating or reducing dairy from the diet can lead to potential nutrient deficiencies, particularly in calcium and vitamin D. It’s crucial to ensure that these nutrients are obtained from other dietary sources or supplements.
- Calcium: Besides dairy, good sources of calcium include fortified plant-based milks, leafy green vegetables, almonds and calcium-fortified orange juice.
- Vitamin D: This vitamin is less prevalent in food but is essential for calcium absorption. Sources include fortified foods, fatty fish, and exposure to sunlight. Vitamin D supplements may also be necessary.
- Protein: Dairy is a rich source of protein, but non-dairy alternatives like legumes, nuts, seeds, tofu and tempeh can help meet protein needs.
The cultural and culinary impact of lactose intolerance
Dairy products, especially cheese, are not just nutritional staples but also cultural icons in many cuisines. For individuals with lactose intolerance, navigating these cultural and culinary landscapes can be challenging. However, the increasing availability of lactose-free and dairy-free alternatives allows for greater inclusion without sacrificing traditional flavours and dishes.
For example, in Italian cuisine, Parmesan and Pecorino Romano cheeses are often used in pasta dishes. Choosing aged versions of these cheeses can allow those with lactose intolerance to enjoy them in moderation. Similarly, in Mexican cuisine, lactose-intolerant individuals can opt for aged cheeses like Cotija instead of fresh varieties like Queso Fresco.
In recent years, there has also been a rise in innovative culinary solutions, such as dairy-free cheese that melts and stretches like traditional cheese, making it easier to enjoy dishes like pizza and lasagna without discomfort.
Embracing a lactose-smart diet
Lactose intolerance, while inconvenient, doesn’t have to mean a complete elimination of dairy, especially cheese, from your diet. By understanding your body’s tolerance level, choosing the right types of cheese, and incorporating lactose-free or dairy-free alternatives, you can still enjoy the flavours and nutrition of dairy products.
The key is to listen to your body, make informed choices, and consult with a healthcare provider or dietitian to ensure you’re meeting your nutritional needs. Whether you’re a cheese lover or just enjoy a glass of milk now and then, there are plenty of options available to keep your diet diverse, delicious and comfortable.
As awareness and innovation in food science continue to grow, the future looks bright for lactose-intolerant individuals who want to keep dairy and cheese on the menu.
References
Overall nutritional content
The nutritional content of cheese in our table comes from the USDA Food Data Central Repository, the Australian Food Composition Database and cheese manufacturers. We realise that there can be variations between different brands and producers. Hence, the numbers we have used are averages.
Lactose levels in mentioned cheeses
¹ Lactose residual content in PDO cheeses
² Detection of lactose in products with low lactose content
³ The analysis of lactose in milk and cheese products by HPLC
⁴ Food Standards ANZ Food Composition Database
⁶ Lactose & Galactose content of cheese
Sabine is the creative force behind Cheese Scientist. She is a sustainable living advocate, a climate change protestor and is pro-choice. And, most relevantly, she is also a lactose intolerant cheese lover.
