The dairy contains a type of sugar called lactose, but many people have trouble digesting it because they have insufficient amounts of an enzyme called lactase, explains Myers, which may result in bloating, gas or even constipation. According to the National Library of Medicine of the United States, about 65% of people have difficulty digesting dairy products as they age
. This does not necessarily mean that you are completely lactose intolerant or allergic. Some people are simply sensitive to it, so you can try drinking low-lactose milk or taking lactase supplements (like this one) to see if it relieves your stomach problems, says Myers
]. you should consult your doctor, ideally a gastroenterologist, so you can rule out the possibility of other serious health issues, says Dr. Poppers.
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