The Wellness Brew - Issue 32

Thyroid care goes wrong in two directions. Some people spend years tired and cold before anyone thinks to check. Others get handed a number barely outside the reference range and start treating something that would have sorted itself out. In this issue, we break down what to do if you fall into either of these buckets.

But first, we filtered the noise — here's what's worth knowing this week.

In September, HHS opened a public comment docket asking what the science says about health effects from electromagnetic fields and radiofrequency radiation, whether current exposure limits are adequate, and where the research gaps are. Plenty of coverage has called this a federal investigation. It isn’t one. A request for information is the step where an agency asks what’s out there before deciding whether to act, and most of them lead nowhere. What makes this one worth watching is who opened it: Robert F. Kennedy Jr., who now runs HHS, was a petitioner in a 2021 lawsuit against the FCC over the same exposure limits his department is now asking the public about. Comments close October 21, and anyone can file one. — US Department of Health and Human Services, docket HHS-OASH-2026-0397, 2026.

The study is real, published in Nature Communications in January, and the number holds up: adults with metabolic syndrome saw LDL fall about 16 mg/dL more than a calorie-matched control group. What the write-ups skip is the protocol. Participants ate 300 grams of rolled oats a day, three meals of it, replacing everything else they normally eat, for two days. That’s seven and a half standard servings, nearly four cups of dry oats. Seventeen people did that. Seventeen more ate matched meals without oats. The same paper also ran the version someone might actually sustain, 80 grams of oats replacing one meal a day for six weeks, and in that arm cholesterol stayed roughly flat. So the result is that a brief extreme intervention moved LDL while a realistic one didn’t, which is close to the opposite of how it’s being passed around. — Klümpen L, et al., Nature Communications, 2026.

The claim going around from a recent podcast is that avoiding sweetness recalibrates your palate and dials down cravings. It’s an appealing idea, one I’ve personally experienced, and it has now been tested properly. Researchers in the Netherlands randomized 180 adults to six months of diets in which 7%, 35%, or 80% of their food and drink was sweet-tasting, supplying about half their daily calories to keep people compliant. At six months there was no difference between the groups in how much they liked sweet taste, no difference in how sweet things tasted to them, no difference in total calories, and no difference in body weight. So while the study didn’t produce the desired outcome, cutting back on sweets is never a bad thing. — Čad EM, et al., American Journal of Clinical Nutrition, 2026.

Thyroid problems are not a niche condition. Using national survey data along with insurance claims, researchers estimate hypothyroidism affects roughly 9.6% of the US population. Among women it's 12.9%. [1]

Every year, a large number of people get handed a lab result sitting slightly outside a reference range, along with almost no explanation of what to do next. 

Two things are worth sorting out before anything else: whether you actually have a problem, and what’s actually in whatever you’re about to take. 

Four numbers show up on a thyroid test, and they answer different questions.

Your pituitary gland monitors how much thyroid hormone is circulating and sends a signal called TSH telling the thyroid to work harder or ease off. The counterintuitive part: a high TSH means an underactive thyroid. The pituitary is shouting because it isn't getting enough back. TSH is the screening test because it moves first and moves most.

T4 is the storage form, and it's most of what the thyroid actually makes. T3 is the active form, converted from T4 in your tissues, and it's what does the work.

TPO antibodies are a different kind of measurement. They don't tell you how the gland is functioning. They tell you whether your immune system is attacking it, which is the cause of most hypothyroidism in countries with enough iodine in the food supply. A positive antibody test explains why something is happening. It doesn't tell you how badly.

The distinction is important. TSH tells you whether there's a problem. Antibodies tell you what kind. Nearly everything sold for thyroid health is aimed at issues with antibodies.

As for what's at stake: overt hypothyroidism and hyperthyroidism, where the hormone levels themselves are out of range, are real conditions with real consequences, and they need to be treated. The large grey zone is subclinical hypothyroidism, meaning a TSH slightly above the reference range with normal T4 and T3. That's where the arguments live, and it's where many people find themselves.

A 64-year-old man with multiple sclerosis was referred to an endocrinologist with results that looked like textbook Graves' disease: low TSH, elevated free T4 and free T3. He was started on methimazole. A month later he felt better, but his numbers hadn't moved, so he was switched to propylthiouracil. They still didn't move. A nuclear scan of his thyroid came back normal. Only then did someone go through his medication list and find 10,000 micrograms of biotin, which he was taking for the MS. He stopped it and five days later his thyroid labs were normal. [2]

Biotin doesn't change your thyroid, but it breaks the test. Most thyroid immunoassays rely on a biotin-binding step, and flooding the sample with extra biotin skews results in opposite directions depending on how the particular test is built: free T4 and free T3 read falsely high, TSH reads falsely low. Together that manufactures hyperthyroidism on paper.

Biotin is in nearly every hair, skin and nails supplement and plenty of multivitamins, commonly at 5,000 or 10,000 micrograms, which is well over a hundred times what food provides. Food-level biotin doesn't interfere. Supplement doses do. Stop taking it three to four days before any thyroid draw, and tell whoever ordered the test that you were taking it.

The second check is simpler. A single elevated TSH is not a diagnosis. TSH runs on a daily cycle, peaking around midnight and bottoming out near midday at roughly half the peak value. Most reference ranges were built from daytime samples. [3] This means a blood draw from the same person at 7am and at 3pm can give you meaningfully different numbers from a thyroid that hasn't changed at all.

Here's a result a lot of people are holding: TSH of 4.8, free T4 and free T3 normal, thyroid antibodies negative.

That is subclinical hypothyroidism, barely. Most labs put the top of normal somewhere around 4.0 to 4.5 and treat a change of 0.7 or more as the threshold for a meaningful shift when comparing a person's own results over time, keeping in mind the time of day the test was given.

The odds favor it resolving. A 2024 meta-analysis followed 1,859 people with subclinical hypothyroidism across eight prospective studies. 44.4% returned to normal on their own. 45.4% stayed where they were. 10.1% progressed to overt hypothyroidism. [4]

People with positive thyroid antibodies were about 2.5 times more likely to progress and meaningfully less likely to normalize. People with a TSH of 10 or above were over eleven times more likely to progress. Someone who’s antibody-negative at a TSH of 4.8 is close to the best version of this finding.

There's also a common explanation that isn't thyroid disease at all. Carrying extra weight raises TSH. A 2026 review in the European Thyroid Journal describes this as an adaptive response rather than a failing gland, and notes that weight loss consistently brings the number back down, though one study found it took more than 10% of body weight over six months before TSH moved. The authors state that current data do not support medication for an isolated mild TSH elevation in someone with obesity. [5]

Age does it too. TSH drifts upward normally as people get older. So does recovery from a recent illness, and occasionally an antibody in the blood that binds TSH and makes the reading look high when nothing is actually wrong.

So the recommendations for this type of person are short and simple. Repeat the test in the afternoon, off biotin, at the same lab. Lose weight if that applies. Get enough iodine without taking too much. Recheck in six to twelve months. If pregnant or trying to conceive, talk to your doctor and consider treating it.Otherwise, more likely than not, you’ll be fine. 

One additional note – Selenium, vitamin D, red light, and aloe: each of them may work, by calming an immune attack on the thyroid. Someone with no antibodies doesn't have that attack so there is nothing there for any of it to act on. And this group tends to be one of the largest buyers in the whole category, because being told your thyroid is borderline, with no further explanation, is exactly what sends a person looking.

Selenium is the most recommended supplement for autoimmune thyroid disease, and the recommendation rests on something narrower than it looks.

A Cochrane review found four randomized trials. Selenomethionine at 200 micrograms lowered TPO antibodies in three of them. But the review's primary outcome, quality of life, had not been measured by a single included study. Neither had symptoms. Neither had change in levothyroxine dose. [6]

So what the evidence establishes is that selenium moves an antibody number, and that nobody has checked whether moving it corresponds to anything a patient would notice.

The follow-up is less reassuring. A 2026 analysis matched 2,347 Hashimoto's patients who took selenium against 2,347 who didn't. The selenium group had higher antibodies, more new autoimmune diagnoses, and higher all-cause mortality over five years. [7] That's observational, and the likeliest explanation is that sicker and more symptomatic people were the ones reaching for supplements, not that the selenium hurt them. But it certainly isn't a finding that argues for taking it.

Vitamin D behaves the same way. Eight randomized trials covering 652 patients: TPO and thyroglobulin antibodies both came down. The review reported no pooled effect on thyroid function, variation between the studies was extremely high, and most of the trials came from a single country with several having unclear randomization. [8]

Antibody levels turn out to be the easiest number to move and the one least connected to how anybody feels.

Start with iodine. The thyroid needs it to build hormone, which makes "more must be better" an easy sell. However, the relationship isn't linear. When populations that already had enough iodide were given more, thyroid antibodies and subclinical hypothyroidism went up rather than down. Schoolgirls in Sri Lanka shifted toward antibody positivity across three years, and Danish adults showed rising antibody rates and subclinical hypothyroidism over four to five. The WHO figure is 150 micrograms a day for adults, 250 in pregnancy. [9] Kelp supplements, a common iodine source, routinely deliver many times that.

Then there's what's in the bottle. Researchers bought ten over-the-counter thyroid support products and measured them. Nine contained actual T3, the active thyroid hormone. Five contained T4. That included all five of the herbal products, none of which listed any hormone on the label. Across the botanicals, daily T3 ranged from 2.73 to 32.13 micrograms, and two of the herbal products delivered T4 at roughly 17 and 91 micrograms per day. [10] Ninety-one micrograms of T4 is a full replacement dose of prescription levothyroxine, sold as an herb.

That study is from 2013, so here's a current label. I went through a popular thyroid support supplement, a $40 bottle with a linked certificate of analysis and a third-party trust badge. Four things stood out.

So here we are, with a supplement that looks like it can be trusted, minimal ingredients on the label (aside from its proprietary blend), and left with some serious doubt. The third-party badge doesn’t settle it either. That kind of testing verifies a product contains what its label claims, which by design says nothing about an ingredient the label leaves off.

Something in this category does have a trial worth taking seriously, and it isn't a supplement.

In a randomized, placebo-controlled study published in 2013, 43 people with Hashimoto's received either low-level laser treatment to the thyroid or a sham they couldn't distinguish from it. Patients, physicians, lab staff and the ultrasound reader were all blinded, and nobody was taking supplements. A month after the final session, everyone stopped their levothyroxine, then went back on only as much as their bloodwork showed they needed. Nine months later the laser group was managing on an average of 38.6 micrograms a day against 106.9 for the sham group, and 95.7% of them had cut back or come off the drug entirely, against 5% of sham. TPO antibodies were roughly half. [14] 

That's a stronger result than anything else here, and it comes with two qualifications.

The first is that it's one research team in Brazil, and nobody has reproduced that specific finding. Two later trials in Turkey ran their own sham comparisons, and in both of them the people receiving real treatment reported less fatigue and better quality of life than the people receiving the fake version. But one of those trials also measured thyroid hormones and antibodies and found no change in either, and the other didn't measure them at all. So independent groups have reproduced a symptom benefit without reproducing the finding that actually matters, which is needing less medication. A 2026 review of all six human studies concluded the therapy is an investigative adjunct that can't be recommended as standard practice. [15] 

The second matters more for anyone reading this with a red light device at home. These trials used a medical laser applied by a clinician to eight marked points on the neck, at an intensity on the order of a hundred times what a consumer LED panel produces. One widely sold at-home panel publishes a total dose of roughly 5 to 7 joules per square centimeter across a 30-minute session, while the trial delivered 28.6 joules at each point in twenty seconds. Nobody has tested an LED panel on a thyroid but it can’t be considered the same treatment.

Aloe vera juice has been popularized as a thyroid remedy on the strength of one study. Thirty women with Hashimoto's and untreated subclinical hypothyroidism drank it daily for nine months, with 15 untreated women for comparison. TSH fell 61%, TPO antibodies fell 56%, and every participant's TSH came back under 4.0. [16]

Unfortunately, the study wasn't randomized or blinded, and it grew out of one of the authors noticing his own labs improve while drinking aloe for an unrelated reason. The paper also states the dose two different ways in two different places, which isn’t a great sign of confidence. There have been no follow-up studies that we could find to replicate this either. 

On safety, oral aloe is a likely though rare cause of liver injury, with at least a dozen published cases, typically appearing somewhere between three and twenty-four weeks after starting. [17] One patient's injury came back when they resumed it.

For someone with a mildly elevated TSH who'd be watching and waiting anyway, trying aloe vera juice is a low-risk choice. But note the exceptions already named: pregnancy, a TSH above 10, or symptoms that are actually bothering you. And the fact that almost half of subclinical hypothyroidism cases resolve themselves over time anyways. 

For anyone taking levothyroxine, this is the highest-yield paragraph here.

The drug is poorly absorbed and easily blocked. Take it with water on an empty stomach, 30 to 60 minutes before eating anything. Keep calcium, iron and multivitamins at least four hours away, because they bind to it directly. Stomach acid reducers interfere. And be consistent, since absorption shifts with whatever else is in your stomach, and a changing routine shows up as a wandering TSH that looks like a dosing problem.

Most people are never told any of this past "take it in the morning." If your dose keeps getting adjusted, how you're taking it is worth checking before the number is.

Thyroid disease is common, and for the people who actually have it the standard treatment works well. 

If you're holding a borderline result, the useful steps are unglamorous. Repeat the test at a consistent time of day and avoid biotin. Find out whether you have antibodies, because that one answer decides whether any of the rest of this applies to you. And if you're already on medication, check how you're taking it before assuming the dose is wrong.

And if you're considering something off the shelf, read the panel before anything else: what's in it, how much of each thing, and whether every active ingredient is actually listed there. Feeling a difference is not the reassurance it sounds like. A product with undisclosed thyroid hormone in it will make you feel something, and that's the reason to put it down. 

Four things you can do this week:

1. Stop biotin before your next thyroid blood draw, and time the draw.
If you take a hair, skin and nails supplement or a multivitamin, check the label for biotin and stop it three to four days beforehand, then tell whoever ordered the test that you were on it. Supplement doses run well over a hundred times what food provides, and they distort thyroid results badly enough that people have been medicated for conditions they never had. While you’re at it, book the draw for the afternoon rather than first thing, use the same lab each time, and don’t let a single result start you on anything. A repeat test a few weeks later costs almost nothing and changes the picture more often than you’d expect.

2. Find out whether you have thyroid antibodies.
TPO antibodies are a separate test from TSH, and plenty of people walking around with a borderline result have never had one run. Ask for it, because the answer sorts you into two very different situations. Positive means an autoimmune process is driving things, you’re meaningfully more likely to progress, and the research on selenium, vitamin D and light therapy is at least pointed at your biology. Negative means something else is going on, often weight or age or a lab that caught you on an off day, and none of those interventions has anything to work on.

3. Leave the “thyroid support” supplements alone.
Skip anything labeled thyroid support or thyroid complex, anything containing desiccated or bovine thyroid, and kelp or high-dose iodine unless you’ve been tested and come up short. When researchers measured ten of these products, nine contained real thyroid hormone, and the herbal ones didn’t say so anywhere on the label. If you want to judge one yourself, the panel tells you most of what you need: look for a dose listed next to each ingredient rather than buried in a proprietary blend, compare anything you recognize against its upper limit, and check that every ingredient named in the marketing copy actually appears in the supplement facts. A third-party seal confirms a product contains what it claims. It won’t catch what the label leaves out.

4. If you take levothyroxine, audit how before you change how much.
Water, empty stomach, 30 to 60 minutes before eating. Calcium, iron and multivitamins at least four hours away. If you’re on an acid reducer, say so, because it interferes with absorption. And keep it consistent day to day, since what looks like a dosing problem is frequently a routine problem. If your TSH keeps wandering and your dose keeps getting adjusted, work through this list before you accept another change.

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Wellness, filtered.

The Wellness Brew

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Disclaimer: The Wellness Brew is for informational purposes only and does not constitute medical advice. The content published here is not intended to diagnose, treat, cure, or prevent any disease or health condition. Always consult a qualified healthcare professional before making any changes to your diet, supplement routine, or lifestyle.