The Body Underneath: Bloodwork, Healing, and the Real Goal
In May of 2024, the number on the screen was 1021.
In February of 2025, the number on the screen was 101.4.
Same test. Same patient. Nine months apart. The reference range printed underneath, both times, said normal was below 20.
I want to start this chapter with those two numbers because they are, in a real sense, the only feedback my body has ever given me that I could rely on. Everything else — how I felt that morning, whether my stomach was settled, whether my last meal had agreed with me — turned out, over the months that followed my diagnosis, to be unreliable in ways I did not see coming. The bloodwork was the one signal that meant what it said.
What the disease is actually doing
The simplest version of celiac disease I can give you:
The lining of your small intestine is covered, on the inside, in tiny finger-shaped projections called villi. The villi are how you absorb nutrients out of food. They give the inside of your gut a huge amount of surface area: square footage, basically, for absorption to happen on. A healthy villus looks like a tall finger reaching into the channel of your gut. There are millions of them.
If you have celiac disease, your immune system mistakes a fragment of the gluten protein for an enemy invader and attacks it. The collateral damage is that it also attacks the villi. Repeated, low-grade, immune-system attacks on the lining of your small intestine, every time you eat a piece of bread, slowly file the villi down. The technical name for this is villous atrophy. In English: the fingers get worn down to stumps. The surface area collapses. You stop absorbing nutrients the way you used to.
When I had my endoscopy in May 2024, the biopsy came back as Marsh 3B villous atrophy, which is a moderate-to-severe grade. My fingers were almost gone. I had been eating bread enthusiastically for decades and my immune system had been at the villi the whole time.
When you stop eating gluten, the immune system stops attacking. The villi grow back. Not overnight — the timeline runs in months and years rather than days and weeks — but they do grow back. The lining repairs itself.
The most important sentence in the book
Here is the thing I want to give you, the sentence that took me longer than it should have to find, the one I'd put on the inside of every newly-diagnosed celiac's refrigerator if I could.
The goal is not to avoid symptoms. The goal is to never let my immune system damage my intestines again.
These sound like the same thing. They are not the same thing.
If your goal is to avoid symptoms, then the absence of symptoms reads like success and the presence of symptoms reads like failure, and you spend your celiac life trying to map the second back to whatever you ate three hours ago. This is what most newly-diagnosed celiacs do. I did it. I spent the first six months keeping a kind of mental ledger — that meal made me sick, that one didn't, this restaurant is fine, that one isn't — assuming the ledger would converge on a clean picture of what was safe and what wasn't.
The ledger did not converge. The ledger was, in a way I did not see at first, garbage data.
Because here is what celiac actually does: it can damage your intestine without making you feel anything. Silent celiac is a real category. There are people who go years with active villous atrophy and zero digestive symptoms. And on the other side, plenty of celiacs feel sick from things that did not, in fact, contain gluten. The mapping between what you ate and how your body reports back is not the clean cause-and-effect that the words I got glutened imply. The damage and the symptoms are two different things, and they don't always travel together.
If you reframe the goal — from avoid symptoms to don't let it damage the lining again — a lot of confusing things get clearer. You stop tying your sense of how-you're-doing to your stomach on any given afternoon. You start tying it to bloodwork, to follow-up endoscopy, to the long arc of where the disease is actually living. You also stop, eventually, having the small internal argument every time you feel fine after a risky meal — well, see, that was probably ok — because probably ok is not the standard. The standard is the immune system did not get a chance to do its damage.
Bloodwork is the scoreboard
If your gut is not going to tell you whether you're doing this right, what does?
The bloodwork. Mostly the bloodwork.
The same tTG-IgA test that diagnosed you in the first place is the test your GI will run again, periodically, to see how your immune system is doing relative to the gluten you are or aren't getting. If you stay strict, the number comes down over months. If gluten is sneaking in somewhere, the number stays elevated, or comes down and then plateaus higher than it should. The number is not perfect. It lags reality by weeks, and individual celiacs vary in how cleanly it tracks. But compared to how did I feel last Tuesday, it is a Hubble Space Telescope.
The other long-term measure is a follow-up endoscopy, usually a year or two after diagnosis, to look at the villi directly. The biopsy report tells you, in a way nothing else can, whether the lining is actually healing. Marsh 3B going to Marsh 1, or Marsh 0, is the answer to is this working in a form your gut will never give you.
My own scoreboard, so far: 1021 to 101.4 in nine months, with another check coming soon. Still above the normal range — that's why my number has a decimal — but a roughly tenfold drop, which my GI was happy with. The trajectory is correct. The next number is the one I'm waiting on.
You may not, for a long time, have the satisfying gut-level I can tell I'm doing this right feeling that you might have hoped for. The lab report is the substitute for that feeling. Get the lab work done. Look at the trend. Let it be the thing that tells you whether the work is working.
Don't promote "I felt fine" into permission
So if my body isn't a reliable referee, why am I being so careful in the meantime? Why bother with the dedicated air fryer and the second toaster and the long restaurant conversations and the polite skip on the holiday pie?
Because the damage happens whether or not you feel it.
That is the whole answer. The immune attack on the villi does not require your participation as an observer. It does not need you to feel sick afterward to do its work. Every cross-contaminated meal is a chance for the lining to take a small hit that nobody, including you, will notice in the moment but that will show up in the bloodwork in eight weeks and in the next biopsy in two years.
If you tie your discipline to whether you feel sick, you will gradually relax it on the meals where you don't feel sick — which is a lot of them — which is a slow leak in the levee that your immune system is delighted to exploit. If you tie your discipline to don't let the lining get hit again, the discipline holds whether you feel anything or not.
This is also, I think, the answer to the question every celiac eventually gets from a well-meaning friend, which is some version of do you really have to be that careful, when one bite probably won't even bother you? The honest answer is: a bite that doesn't bother me can still let the immune system pick up where it left off. The bother is not the disease. The disease is the damage. I am not optimizing for the bother. I am optimizing for the damage. That sentence, said warmly and without any heat, ends most of those conversations.
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