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Dairy

Worst

You need calcium in your diet, and an easy way to get it is from dairy products such as milk and cheese. But, for the lactose intolerant, these can cause diarrhea, gas, and abdominal bloating and cramps.

Lactose intolerance, a common problem, occurs when people don't make enough lactase, an enzyme that breaks down lactose (the sugar found in milk). Celiac disease, Crohn's disease, and chemotherapy can damage the intestines, which also can lead to lactose intolerance.

If you're lactose intolerant, staying away from dairy is probably your best bet.

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