Lactose intolerance

Reviewed by Dr. Nikita Dinger, Founder & CEO, BioMeBar. Last reviewed 7 October 2026.

Click to WhatsAppTake the Gut Quiz →

What it is

Lactose is the sugar in milk. To absorb it you need an enzyme called lactase in the small intestine. In many people lactase activity falls after childhood, which is called lactase non-persistence and is normal in much of the world, including large parts of India. When lactose reaches the colon undigested, bacteria ferment it, and that is what produces the symptoms.

Lactose intolerance is therefore a digestion issue, not an allergy to milk protein. The two are easy to mix up, and the lactose intolerance vs milk allergy page spells out the difference. Lactose is also one of the FODMAPs, covered under FODMAP sensitivity.

Common symptoms

Symptoms usually start thirty minutes to two hours after dairy:

• Bloating and a swollen belly
• Gas and loud gut sounds
• Abdominal cramps
• Loose stools or diarrhea, sometimes urgent
• Nausea in some people
• Symptoms that depend on amount, for example, fine with a splash of milk in tea but not with a tall glass of lassi

A hydrogen breath test, arranged by a doctor, can confirm it. Many people simply notice that an elimination of milk eases things and later work out their personal limit.

How gut bacteria may be involved

Undigested lactose draws water into the colon and is fermented by gut bacteria into gas and short-chain fatty acids. Gut bacteria differ in how well they handle lactose, and some studies suggest that regular small amounts of dairy may help some people tolerate more through bacterial adaptation, though this is not certain and varies between individuals.

Fermented dairy shows why. Curd, dahi and chaas contain bacteria that carry their own lactase, and fermentation has already used up some of the lactose, so many lactose-intolerant people handle them better than milk. Aged cheese and ghee contain very little lactose. These are general tendencies, not rules. See fermented Indian foods for how they differ.

Diet and everyday habits

Most people do not need to give up dairy entirely. They find their own limit. Some approaches:

• Try fresh curd, dahi or chaas first; many tolerate them where milk causes trouble
• Use smaller amounts of milk spread through the day, and take it with a meal rather than alone
• Pick paneer, ghee, butter and hard cheese, which are generally lower in lactose
• Look for lactose-free milk or add lactase enzyme drops or tablets, after asking your pharmacist
• Check hidden lactose in some bread, sweets, ready gravies, protein powders and medicine fillers
• Cover calcium from other sources: ragi, til (sesame), almonds, soya, tofu, and green leafy sabzi like methi and drumstick leaves
• Ask your doctor about vitamin D, since many Indians are low, whether or not they eat dairy

For other trigger foods see the food sensitivity elimination diet page.

Click to WhatsAppTake the Gut Quiz →

When to see a doctor first

Lactose intolerance is usually harmless but other conditions can imitate it. See a doctor first if you have:

• Blood in stool, or unexplained weight loss
• Hives, swelling, wheeze or vomiting soon after milk, which suggests allergy and needs urgent care
• Symptoms that do not improve despite cutting out dairy
• Chronic diarrhea, anaemia or night-time symptoms
• Poor growth, or long-lasting diarrhea in a child
• Signs of poor calcium intake, such as bone pain or frequent fractures
• Symptoms starting suddenly after a gut infection or after starting a medicine

Sometimes lactose symptoms appear secondary to another gut condition such as coeliac disease or IBS, so ongoing symptoms deserve review.

How BioMeBar approaches it

BioMeBar looks at lactose as part of a broader picture. We use your gut profile and symptoms to match a personalised synbiotic, and we pay attention to the ingredients, since some products contain dairy-derived components. Our food and lifestyle guidance helps you test dairy in Indian foods at your own pace while keeping calcium intake up, and check-ins track your progress. We ask you to share your tolerance level with us. BioMeBar does not diagnose, treat or cure any condition, and a synbiotic is not a substitute for medical care.

Common questions

Is curd safe if I am lactose intolerant?

Many people tolerate it much better than milk, because the bacteria in curd help digest lactose. Try a small portion and see.

Do I need to avoid all dairy?

Usually not. Most people can find a comfortable amount. Complete avoidance is rarely necessary unless you have a milk protein allergy.

Can lactase tablets help?

They are widely used and many people find them useful with a dairy meal. Check with your pharmacist about the right product.

Is A2 milk better for lactose intolerance?

A2 milk contains the same lactose as regular milk, so it will not help if lactose is the problem.

Sources

• United European Gastroenterology evidence-based consensus on the diagnosis and management of lactose intolerance
• NIH Consensus Development Conference statement on lactose intolerance and health
• ICMR-NIN Dietary Guidelines for Indians
• Rome IV diagnostic criteria for functional bowel disorders

Talk to us

If you would like to know whether BioMeBar can support you, message us on WhatsApp. Tell us your symptoms and your pincode and we will take it from there. Not sure where to start? Take the free gut assessment, which takes about three minutes.

Click to WhatsAppTake the Gut Quiz →

BioMeBar provides nutrition and gut health guidance and does not replace medical care. See a doctor for severe, persistent or worrying symptoms.