If drinking a glass of milk leaves you feeling bloated, gassy, or rushing to the bathroom, you're not alone. Lactose intolerance affects an estimated 1 in 6 Australians, making it one of the most common digestive conditions in the country. But having lactose intolerance doesn't mean you have to give up dairy entirely—understanding the condition is the first step to managing it effectively.
What Exactly Is Lactose Intolerance?
Lactose intolerance occurs when your body doesn't produce enough lactase, the enzyme needed to digest lactose—the natural sugar found in milk and dairy products. Without sufficient lactase, lactose passes undigested into your large intestine, where bacteria ferment it, producing gas and drawing water into the bowel.
It's important to distinguish lactose intolerance from a milk allergy. Lactose intolerance is a digestive issue that causes discomfort but isn't dangerous. A milk allergy, on the other hand, is an immune system response that can be severe or even life-threatening. If you experience symptoms like hives, difficulty breathing, or swelling after consuming dairy, seek medical attention immediately—that's an allergic reaction, not lactose intolerance.
Types of Lactose Intolerance
Not all lactose intolerance is the same. Understanding which type you have can help you manage it more effectively.
Primary Lactose Intolerance
This is the most common type and develops naturally with age. As babies, we produce plenty of lactase to digest breast milk, but production naturally decreases after weaning. For some people, this decrease is significant enough to cause symptoms when consuming dairy as adults. This type often begins in adolescence or early adulthood and is largely determined by genetics.
Secondary Lactose Intolerance
This type occurs when illness or injury damages the small intestine, temporarily reducing lactase production. Conditions like gastroenteritis, coeliac disease, Crohn's disease, or even a course of antibiotics can trigger secondary lactose intolerance. The good news is that this type often improves once the underlying condition is treated.
Congenital Lactose Intolerance
Extremely rare, this type is present from birth and means babies cannot digest breast milk or standard formula. It requires immediate medical attention and lifelong dietary management.
Recognising the Symptoms
Symptoms of lactose intolerance typically appear 30 minutes to 2 hours after consuming dairy. Common symptoms include:
- Bloating and abdominal swelling
- Stomach cramps and pain
- Excessive gas and flatulence
- Diarrhoea or loose stools
- Nausea, and occasionally vomiting
- Rumbling or gurgling sounds from the abdomen
The severity of symptoms varies greatly between individuals. Some people can drink a full glass of milk with only mild discomfort, while others react to even small amounts of dairy. Your personal threshold depends on how much lactase your body produces and the sensitivity of your digestive system.
Getting a Diagnosis
If you suspect you have lactose intolerance, it's worth getting a proper diagnosis rather than self-diagnosing. Several other conditions can cause similar symptoms, and eliminating dairy unnecessarily can lead to nutritional deficiencies.
Your doctor may recommend:
- Hydrogen Breath Test: The most common diagnostic tool. You drink a lactose solution, and your breath is tested over several hours. If you're lactose intolerant, undigested lactose will ferment and produce hydrogen, which shows up in your breath.
- Elimination Diet: You remove all dairy from your diet for 2-3 weeks, then gradually reintroduce it while monitoring symptoms.
- Blood Glucose Test: After consuming lactose, your blood sugar is measured. If levels don't rise, it suggests the lactose isn't being digested and absorbed properly.
Managing Lactose Intolerance
The good news is that lactose intolerance is highly manageable. Most people don't need to eliminate dairy entirely—they just need to find their personal tolerance level and make smart choices.
Know Your Threshold
Most people with lactose intolerance can handle 12-15 grams of lactose per day (about one cup of milk) without significant symptoms, especially when consumed with other foods. Start with small amounts and gradually increase to find your personal limit.
Choose Lower-Lactose Dairy
Not all dairy products contain the same amount of lactose:
- Hard cheeses (parmesan, aged cheddar) contain virtually no lactose—the aging process breaks it down.
- Yogurt contains live cultures that help digest lactose, making it easier to tolerate than milk.
- Butter has only trace amounts of lactose and is usually well-tolerated.
- Soft cheeses (cottage cheese, ricotta) contain more lactose than hard varieties but less than milk.
Try Lactose-Free Products
Lactose-free milk, yogurt, and ice cream are widely available in Australian supermarkets. These products contain the same nutrients as regular dairy—manufacturers simply add lactase enzyme to pre-digest the lactose. They taste slightly sweeter than regular dairy because lactose is broken down into its component simple sugars.
Use Lactase Supplements
Over-the-counter lactase supplements (like Lacteeze) can be taken just before eating dairy. They provide the enzyme your body lacks, allowing you to enjoy dairy foods with reduced or no symptoms. These are particularly useful for dining out or social situations where you can't control the ingredients.
Ensuring Adequate Nutrition
Dairy is an important source of calcium, vitamin D, and protein. If you're reducing your dairy intake, it's essential to obtain these nutrients elsewhere.
Calcium Sources
- Calcium-fortified plant milks (check the label—not all are fortified)
- Canned fish with bones (salmon, sardines)
- Leafy green vegetables (kale, bok choy, broccoli)
- Tofu made with calcium sulfate
- Almonds and sesame seeds
Vitamin D Sources
- Sunlight exposure (10-15 minutes of Australian sun provides adequate vitamin D for most people)
- Fatty fish (salmon, mackerel, sardines)
- Fortified foods and supplements
- Egg yolks
Lactose intolerance doesn't mean giving up dairy forever. Most people can enjoy cheese, yogurt, and even some milk by understanding their personal threshold, choosing lower-lactose options, and using lactase supplements when needed.
Living Well with Lactose Intolerance
With the wide range of lactose-free and low-lactose products available today, living with lactose intolerance has never been easier. Australian supermarkets stock lactose-free versions of almost every dairy product, and restaurants are increasingly aware of dietary requirements.
The key is to experiment, keep track of what works for your body, and remember that your tolerance may vary day to day. Stress, illness, and what else you've eaten can all affect how you respond to dairy. Be patient with yourself, and don't be afraid to ask questions when eating out.
Most importantly, don't let lactose intolerance diminish your quality of life. With proper management, you can still enjoy the foods you love and maintain optimal nutrition for years to come.