Hair, Skin, and the Nutrient Gap

In the third week of March I was rinsing conditioner out of my hair and looked down at the drain and thought, with complete clarity, oh, no.

I have had this conversation with patients perhaps forty times. I have a small speech about it. I know the mechanism, the timeline, and the reassurance, and I have delivered all three with what I hope was warmth.

Standing in my own shower, the speech was not available to me. What was available was a flat, undignified panic.

I am including this because I think the honest version is more useful than the composed one, and because the thing that fixed it was not reassurance. It was going and getting the data.

What is actually happening

The shedding that follows rapid weight loss is, in the overwhelming majority of cases, telogen effluvium.

Hair grows in cycles. At any moment most of your follicles are in the growing phase and a minority are in the resting phase, after which the hair is shed and replaced. A significant physiological stressor — a large energy deficit, a rapid change in body weight, a serious illness, childbirth, a major surgery — can push an abnormally large share of follicles into the resting phase at once.

Two crucial features:

It is delayed. The shed happens roughly two to four months after the trigger. This is why it feels like it came from nowhere, and why the month you notice it is not the month that caused it. My shed in March was the deficit of December and January arriving on schedule.

It is diffuse and temporary. It thins across the whole scalp rather than in patches, and it regrows over about six to nine months once the stressor resolves. It is not the same category of thing as androgenetic alopecia or an autoimmune process, and it does not mean you are going bald.

Is it the drug? Mostly, no — it is the weight loss. This shed occurs after bariatric surgery and after aggressive dieting, in people who have never taken a GLP-1. That said, alopecia was reported as an adverse event more often than placebo in some trials, notably tirzepatide’s SURMOUNT-1, so I am not going to tell you the drug has nothing to do with it. The honest position is that rapid loss is the dominant driver and the drug is what made the rapid loss possible.

The mechanism was not what reassured me. What reassured me was that my ferritin came back low-normal and there was something to actually do.

What I did about it

I did what I would have told a patient to do, three weeks later than I should have.

I checked labs. Ferritin, iron studies, vitamin D, B12, TSH, and a CBC. Mine came back with a low-normal ferritin — iron stores at the bottom of the reference range, which is not a diagnosis of anything but is a plausible contributor and is trivially correctable. Everything else was fine.

I got serious about protein again. I had been drifting. Not dramatically, but the log did not lie: my seven-day average had slipped from about 120 grams to the low nineties across February, because appetite suppression at 1.7 mg is real and I had let the schedule slide.

This is precisely where Zenday App has earned its place for me. A generic calorie tracker would have told me I was eating very little, which I knew and was pleased about. What I needed was the protein average against my target, plotted over weeks rather than days, in a tool that assumes the whole point is protecting lean tissue rather than minimising calories. Seeing that drift laid out was what got me to fix it, and it is the same reason I have not been able to go back to old-fashioned food logging — this treatment has a different failure mode, and it needs a tool that knows what the failure mode is.

I kept the creatine going. Minome’s GLP-1 Foundation, the same scoop I started in February, which by month five was doing the least interesting and most useful thing a supplement can do: nothing I noticed, every day, without argument. The sodium in it also stopped mattering to me until a week in April when I ran out for four days and the cramps came back, which is its own kind of evidence.

I tried a topical for the face, which I want to be precise about because this is the part where I am most likely to be accused of selling something.

I started using Minome’s GLP-1 Glow in mid-April, twice a day. My skin is better hydrated and the crepey quality along my jaw is less obvious in the morning than it was. That is a genuine change and it is a small one, and I am reporting it with all the usual caveats about a sample size of one person who wanted it to work.

What it did not do — what nothing applied to skin does — is put fat back in my face. The hollowing under my cheekbones is fat loss, it is the reason “Ozempic face” has a name, and no serum reaches it. If the volume is what bothers you, the honest referral is to a dermatologist and the honest conversation is with your prescriber about the rate of loss. A topical is for the surface. I use one because the surface is also a thing.

I slowed down. I had escalated to 1.7 mg in early March. After the labs I talked to my endocrinologist and we agreed to hold there rather than climbing further. The rate of loss over months two and three had been faster than either of us particularly wanted.

The nutrient gap nobody plans for

Here is the broader problem, and it deserves more attention than it gets.

You are eating perhaps half the food volume you were eating in October. Your requirement for protein has gone up, because you are in a deficit and trying to preserve muscle. Your requirement for iron, B12, vitamin D, calcium, and everything else has not gone down at all.

Half the food, the same requirement. That arithmetic does not resolve itself.

I am not going to tell you to take a handful of supplements, because supplementing blindly is how people end up with expensive urine and occasionally with harm. What I will say:

• Protein is the first priority, ahead of every micronutrient question, and it is the one most people miss.
• Check rather than guess. Baseline labs and a repeat at six months turn an anxiety into a number.
• Some groups need more attention: anyone vegetarian or vegan, anyone with heavy periods, anyone with prior bariatric surgery, anyone over sixty-five.
• The risk rises with duration. A three-month course and a three-year course are different propositions, and almost all of us are now in the second category.

About the face

The other thing people ask me about, always slightly sheepishly.

“Ozempic face” is facial fat loss. The face has discrete fat compartments, and when body fat falls they deflate — which reads as gauntness, hollowing under the eyes, and a slightly older appearance. It is more pronounced with age, with less elastic skin, and with faster loss.

It is not a drug effect. It happens with equivalent weight loss from any cause. The reason it acquired a brand name is that these drugs made that magnitude of loss common in people who would otherwise never have experienced it.

What helps: losing more slowly, keeping lean mass up, and not pursuing a weight below what suits your frame. What does not help is any of the products currently being marketed to you about it.

Where things stand

Down 13.4% at five months, holding at 1.7 mg, iron supplemented, protein back where it belongs. The shed slowed by mid-April and I can already see the regrowth at my hairline, which is the tedious, unphotogenic, entirely expected course of this.

The lesson I would take from month five, if I were reading this rather than writing it: the interesting problems in this treatment are not the ones in the first month. They arrive on a delay, they announce themselves in a shower, and the answer is almost always to go and measure something instead of catastrophising.

I wrote up the evidence side of this separately, because I got asked about it constantly: the best supplements for GLP-1 hair loss, which explains the two-to-four month lag that makes the timing so confusing, and what to actually eat, which is where the protein problem underneath it gets solved.