On a warm summer’s day, many of us like to enjoy an ice-cream cone or milkshake. In the winter, we might reach for a glass of eggnog or a hot chocolate. However, for those with lactose intolerance, these treats might not be a good idea. Lactose intolerance occurs when the body is unable to digest lactose, a type of milk sugar found in dairy products like butter, milk, and cream.

The difference between lactose intolerance and a milk allergy (or casein allergy) is the immune response to ingesting dairy products. Patients with milk allergy are allergic to the protein (or casein and whey) found in milk and often suffer from hives, swelling, and even anaphylaxis after eating them. However, those who are lactose intolerant are unable to digest lactose, and suffer symptoms of bloating, diarrhea, and flatulence in response. The most common symptoms associated with lactose intolerance include the following:

1. Stomach pain and cramps

Abdominal pain and cramping are a common symptom of lactose intolerance. The undigested lactose in the body causes fermentation, which then leads to cramps due to the buildup of excess gas in the colon. If you have consistent pain or cramping, it may be time to pay attention to what you are consuming and speak to your doctor.

2. Diarrhea

Having an emergency bathroom break after consuming dairy products is the result of sugar drawing liquid into the gut. This increase of liquid is what leads to the urgent need to use the washroom. Symptoms of intolerance usually begin 30 minutes to two hours after eating or drinking products containing lactose.

3. Gas and bloating

An increase of excess gas in the body is due to the fermentation of lactose in the colon. This fermentation creates a build up gas, leading to bloating. This gas can also cause discomfort due to the carbon dioxide and methane it contains. Having audible stomach gurgling or rumbling is another sign of excessive gas.

4. Constipation

This can occur when the stool in your colon moves too slowly. Luckily for many, constipation is not a typical symptom of lactose intolerance because the colon tends to draw water into the digestive tract. Dairy free probiotics can help improve the health of the digestive tract with healthy bacteria.

5. Mouth ulcers

Ulcers of the mouth caused by lactose intolerance will typically disappear on their own when dairy is removed from one’s diet. Dr. Michael Greger believes that milk proteins embed themselves in the lining of the mouth, where our body sees them as foreign proteins and attacks them. Dr. Greger found that when his patience reintroduced milk to their diets, their ulcers reappeared as well. If you find yourself suffering from any of these symptoms, taking a break from dairy products could be a good next step. Be sure to consult a doctor if your symptoms are persistent.