A version of this post first appeared on Dr. Ayala’s Open Salon blog. Are most Americans lactose intolerant? Do all dairy products contain lactose? How critical is it to stick to a lactose-free diet?

This question originally appeared on Quora. Answer by Ti Zhao, biomedical engineer: Sort of. It’s somewhat complicated since there are genetic as well as environmental components to this. Natural ...

Lactose intolerance occurs when your body is unable to digest the sugar lactose, which is found in milk and milk products. This causes uncomfortable symptoms including gas, bloating, cramps and even ...

Regretting that slice of pizza or double-scoop ice cream cone? If you’ve ever felt bloated, gassy or just plain unwell after a dish of ice cream or a meal laden with cheese, then you may well know the ...

What do pizza, milk shakes and ice cream have in common besides being delicious and being loaded with calories? Surprisingly, majority of the people on this planet find it difficult to digest these ...

Lactose intolerance, often seen as a simple enzyme deficiency, may have a new explanation. Scientists are exploring how the ...

Lactose, the sugar found in milk, is digested in the intestine by the enzyme lactase. People who lack this enzyme suffer from a condition called lactose intolerance. In their bodies, milk sugar moves ...

Q. Why do some people become lactose intolerant as they age? A. All of us are born with the ability to make an enzyme called lactase, which helps our small intestines digest the otherwise unwieldy ...

It's estimated that up to 50 million Americans are lactose-intolerant to one degree or another: They can't digest dairy products. It can be tough avoiding dairy, but that doesn't mean lactose-free ...

After childhood, about two-thirds of the world’s human population loses the ability to digest milk. As far as we know, 100% of nonhuman mammals also lose this ability after weaning. The ongoing ...