Lactose intolerance and milk allergies are not the same, it is different conditions with various causes. Lactose intolerance is tied with having problems digesting lactose. In contrast, milk allergies are caused by the response of your immune system to some of the proteins in milk and dairy products.
A milk allergy most of the time shows itself in the first year of life, while lactose intolerance is more likely to appear later. Lactose intolerance causes unpleasant symptoms, while a milk allergic reaction can endanger your life.
And still, lactose intolerance and milk allergies can produce similar symptoms. If after eating or drinking milk-contained products you feel gassy and bloated or if it causes diarrhea or nausea, you may have either condition.
Then what’s the difference? A dairy allergy is an immune system response to milk protein. In addition to feeling bloated or causing diarrhea, symptoms of a dairy allergy can include hives, wheezing, vomiting, cramps, and skin rashes. Milk intolerance results from inadequate levels of lactase. Again lactose intolerance can cause a lot of discomforts, it isn’t life-threatening, while a milk allergy can be.