一只蜱虫咬了他，从此他不能吃牛肉：七年后，这个营养师自己养起了四百只鸵鸟

The conclusion first: this episode is about a man who cannot eat beef, and whose solution was to start farming ostriches.

It sounds like a joke, but every step of it has its logic.

He lives in Kentucky, and his profession is nutritionist.

Which is to say: what other people ought to eat is already his day job.

In 2017 he was away for work and had a beef sandwich at lunch.

Not long after, his skin started reddening and itching.

He could not work it out at the time, because the sandwich could not have been more ordinary.

The diagnosis came later: the problem was not the sandwich, it was him.

He had become allergic to red meat.

Red meat means the meat of mammals: cattle, sheep, pigs.

The strange part is that he had eaten it for thirty-odd years without incident.

How does someone suddenly become allergic to something they have eaten half their life?

The answer is a tick.

A tick hides in the grass, is very small, and people often feel nothing when it bites.

Its saliva carries a kind of sugar called alpha-gal.

That sugar occurs naturally in the bodies of most mammals; humans and a few primates are the exception.

So the human immune system has never encountered it.

After a tick bite, the sugar enters the blood, the immune system treats it as an intruder, and it remembers.

From then on, eating the meat of any mammal triggers the same set of reactions.

The condition is called alpha-gal syndrome; in plain terms, red-meat allergy.

It has one unusual feature: it is not something you are born with. An insect installs it.

What is worse is how far it reaches.

Not eating beef, lamb and pork is only the first layer.

If someone is grilling in the yard and he smells the smoke, he can react to that too.

The shell on a lot of capsules and tablets comes from animals, so even taking medicine means reading the ingredients.

What he can still eat is seafood, fish, chicken and eggs.

That list is not actually narrow, but he has a line that puts it well: there are only so many ways to cook a chicken.

Now for the part where he solves it.

What he really wanted was that particular taste and texture.

Then he found ostriches.

The ostrich is the largest living bird, taller than a person when grown, extremely fast on foot, and unable to fly.

The key point is this: an ostrich is a bird, not a mammal.

There is no such sugar in its body, so eating it does not trigger the allergy.

And in every other respect ostrich meat comes very close to beef.

It is red, high in iron, the cut texture is nearly indistinguishable from beef, and cooked it tastes very similar.

The first time he ate it, he described the feeling as bringing back the old days.

At this point the usual version of the story would end: a man found a substitute.

But he went one step further.

He and some partners opened an ostrich farm and raise them himself.

There are more than four hundred on it now, with a plan to expand to seven hundred next year.

The meat is sold too, and it is not cheap: over twenty dollars a pound for ground, more than forty for the good cuts.

This is what I actually want to say.

He cannot undo the tick bite.

There are usually only two ways to handle something like that: accept the loss, or keep dwelling on what is gone.

He took a third route — find something his body does not reject that meets the same need, and then turn it into a living.

Think about it:

There is something you are certain you can never have again.

Do you sit with it for years, or go and find something that can take its place?