The symptoms came on gradually. They began early in my 30s. I had occasional but severe heartburn. Once in a while, stomach cramps doubled me over. As I began the countdown to menopause, heartburn became weekly episodes. The doctor's test for gall bladder problems, based on the rising frequency of gut pain, proved nothing. The incidences of pain grew worse during peri-menopause.

I dismissed the pain as "something I ate," and let it go. As I've since learned, that was truer than I realized. It just wasn't the multiple foods I thought causing it all.

It was a chance comment from my 35-year-old manager that clued me in.

In a small, family-owned bead store, the day's shift was all women. While we bagged and tagged merchandise, we talked about food. The things we liked to cook, our favorite recipes, and what we had to avoid.

"I can't eat dairy products," the manager said. "Sometimes the cramps in my gut and chest hurt so bad that I think I'm going to die." She shook her head. "It always happens if I eat too much dairy."

"Like you're having a heart attack?" I asked. "Pain so bad that you're doubled over? Like I was the other day?" (I was at work when that happened.)

"Just like that," she said. "I can get away with a few mouthfuls once in a great while. But, not every day – and definitely not flat out milk stuff." She tilted her head. "You might want to look into it."

"But, I've always been able to drink milk."

"Humans aren't supposed to, though," she said.

"What?"

"Look it up," she said.

I blinked. "I wonder..."