My daughter, through my nut-butter toast. (Whitney Pipkin)

Peanut butter got me through that dreaded first trimester of pregnancy. When all other protein sources made my stomach churn, I spooned it onto bananas, toast and oatmeal. I even put it on carrots.

I ate more than I usually would, partly because I love it (eat what you crave, right?) and partly because I’d read that early introduction of allergy-inducing foods — even in utero — could help prevent allergies later.

The research tides were turning, and my baby was not going to have a peanut allergy.

Once she was 6 months old and welcoming her first solid foods, I jumped at the  advice as it emerged to introduce peanuts to infants before one year of age. Researchers found that early and frequent introduction of the peanut protein to children as young as 4 months who were high risk for allergies reduced the likelihood of an allergy by age 5.

This could explain why countries whose parents freely dole out peanuts from infancy, such as Israel, don’t have such high rates of the allergy or peanut-free school zones. In America, about 2 percent of children are allergic to peanuts, a figure that has more than quadrupled since 1997 for reasons scientists are only beginning to unravel.

Our family had no history of a peanut allergy and, as a fanatic for the legume, I wanted anything but a peanut prohibition at the family table. We were great candidates for applying this latest research at home.

I even discussed the research with an allergist after my daughter’s eyes had inexplicably swollen one morning. We thought she might be allergic to our nanny’s cat since my husband has cat and seasonal allergies; I have none. The allergist said to continue trying new foods, even peanut butter, and to report back about any reactions.

So, one unremarkable morning when my daughter was 8 months old, I did. I spooned a dab of my beloved peanut butter onto her banana chunks and watched to see if she’d like it as much as her mama. I almost forgot to watch for an allergic reaction, until I saw a red half-circle forming on her chin.

Ten minutes later, we were headed to the emergency room, panicked.

The redness had spread to her eyes and burst into tiny splotches of hives that spread in a raccoon-like pattern down her chubby cheeks. Her elbows and knees broke out in hives, too, and she began to itch and whimper.

In my hysteria, I somehow found the allergist’s card and called him, not sure whether to use the Benadryl or the Zyrtec he had given me as a precaution. He was away from his desk. The symptoms were worsening.

As my mama sirens escalated to a full roar, I called 911. Yes, we should come to the ER, the operator said.

After eschewing the ambulance, my husband decided to put on the flashers and pretend we could go through stoplights. It was that bad. Watching from the backseat, the whites of her eyes had begun to swell and take on a jelly-like appearance. Though she showed no signs of wheezing or trouble breathing, I feared the worst.

The ER doctors were wonderful, whisking us back right away yet remaining calm. The Benadryl I’d given her at home began to take effect, and they added a steroid to flush the allergens from her system. We stayed a couple of hours for monitoring, and I watched my baby’s cherubic face return.

After a harrowing morning, the ER doctors assured us we had done the right things (or is that what they tell all shaken parents?). We had read the latest research and followed a doctor’s advice. We reacted quickly when things went wrong.

And, mom guilt aside — I gave her that peanut butter! — now we know.

It took a few days and another visit to the allergist for this “diagnosis” to sink in. They drew blood (speaking of harrowing), ran tests and confirmed that her allergy is, indeed, severe. She also appears to be allergic to tree nuts, if her reaction to a smidge of pesto on eggplant is any indication.

When I tell people she has a peanut allergy at such a young age, I get a mix of pity and advice. “She’ll probably grow out of it,” they say, but I’ve read that only one in five kids do.

As any mother in this situation would say, I didn’t want this for her. And, if I’m honest, I didn’t want this for me either.

As a food writer with a penchant for adventurous eating, I found myself mourning the carefree mothering style I had envisioned. I had to repent of the way I’d rolled my eyes at “allergy parents” in the past who lost sleep over “may contain traces.”

Now, I study them. I recently overheard a mother delineating the nuances of her son’s peanut allergy as she ordered him a brownie. It needs to be nut-free, she said, but it’s okay if it’s prepared on the same surface as something with nuts. How did she know? How many trials and errors did it take to definitely say, “He can eat this, not that?”

I’m no scientist, but I feel like I’ve joined the cautious ranks of some unofficial club, the Union of Concerned Parents, perhaps.

I’ve added the peanut-free label to her childcare rap sheet and stashed my Costco-sized jar in the unfinished storage. Looking back, I recall a drip of my peanut butter ice cream sandwich giving her a splotch of hives down her neck, though I thought it was mosquito bites at the time. I’d hate for a thoughtless, post-peanut kiss to leave its mark, now that I know.

As she grows older, I’m preparing for more menu scouring and birthday party prohibitions to be our future. As adventurous an eater as I am and as I’d like her to be (“My kid? She’ll eat anything.”), I remember that ER trip too vividly. It’s just not worth the risk.

And if, for the time being, that means trading my blithe parenting approach to become a sentry against all things peanut, so be it. I’ve become an EpiPen-carrying member of the tribe, waiting for a cure and test-batching recipes for nut-free pesto. Because, for now, that’s the kind of parent she needs.

Whitney Pipkin is a freelance journalist and editor. She tweets @whitneypipkin and blogs at whitneypipkin.com.

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