Hashimoto's in Norway: Why So Many Women Are Told They're Fine

Something I've noticed over the years running this store is that a disproportionate number of the people who message me about thyroid issues are women in Norway. Not just women generally, but women in their thirties and forties who have already been to the doctor, already had their TSH checked, been told everything's fine, and are still sitting there cold and exhausted and watching their hair thin out. And the frustrating thing is that in many of these cases, fine probably isn't accurate. TSH within range is not the same thing as a thyroid that's working well, and in a country with specific dietary and environmental factors that affect thyroid function, the gap between "normal on paper" and "struggling in practice" can be significant.

Hashimoto's thyroiditis is the most common cause of hypothyroidism in Norway and across the developed world. It's an autoimmune condition where the immune system attacks the thyroid gland, gradually reducing its ability to produce hormone. It is significantly more prevalent in women than men. It can be present and causing symptoms for years before TSH moves far enough outside the reference range for most doctors to act. And there are specific factors in the Norwegian context, selenium levels in the soil, vitamin D deficiency through the dark months, iodine in the diet, that make the picture here worth understanding separately from the general research. This post is about that, and about where the research on red light therapy fits into it.

Why Norway specifically

Selenium is an essential mineral for thyroid function. The thyroid contains more selenium per gram of tissue than almost any other organ, because it uses selenium-dependent enzymes to convert the inactive thyroid hormone T4 into the active form T3. Norwegian soils have relatively low selenium content compared to many other countries, and while the Norwegian diet includes some selenium from seafood and meat, there are ongoing questions about whether average intakes are adequate, particularly for people who don't eat a lot of fish. Low selenium is associated with increased risk of autoimmune thyroid conditions, including Hashimoto's, and with worse outcomes when the condition is already present.

Vitamin D is the other piece. The immune dysregulation that underlies autoimmune conditions like Hashimoto's is closely linked to vitamin D status, and low vitamin D is associated with higher thyroid antibody levels in people who already have Hashimoto's. In Norway, meaningful vitamin D production from sunlight is essentially impossible from October through March. Most people here are vitamin D deficient or insufficient for a significant part of the year without supplementation. If you're not supplementing through the winter and you have Hashimoto's, or a predisposition to it, that's worth knowing.

Iodine sits in the middle. Too little impairs thyroid hormone production. But in autoimmune thyroid conditions specifically, there is evidence that very high iodine intake can worsen the autoimmune process rather than help it. Norway's iodine intake comes largely from dairy and seafood, and while overt deficiency is uncommon here, the relationship between iodine and Hashimoto's is less straightforward than the general "iodine is good for the thyroid" framing suggests. Ask yourself: how much of what you've read about thyroid health actually accounted for the difference between iodine deficiency hypothyroidism and Hashimoto's autoimmune hypothyroidism? They're treated as the same thing but they're not.

The testing problem

Standard GP thyroid testing in Norway, as in most of Europe, typically starts and often ends with TSH. That's a reasonable first screen, but it's a poor sole diagnostic tool for Hashimoto's specifically. TSH can remain within the normal reference range for years while the immune system is actively destroying thyroid tissue and antibody levels are elevated. By the time TSH shifts, the damage is already substantial.

The more useful tests, and the ones I'd push for if you suspect Hashimoto's, are free T3, free T4, and the thyroid antibodies: TPOAb (thyroid peroxidase antibodies) and TgAb (thyroglobulin antibodies). Elevated antibodies, even with normal TSH, indicate that the autoimmune process is active. It's also worth knowing that antibody levels can fluctuate, so a single normal result doesn't rule it out. This isn't me being high and mighty about what GPs should be doing, most are working within systems that aren't set up for nuanced thyroid investigation. But you can ask for these tests specifically by name, and in many cases you can get them.

Where red light therapy fits

I've written separately about the Höfling research in more detail, the three Brazilian studies that found low-level laser applied over the thyroid in Hashimoto's patients was associated with reduced antibody levels, improved thyroid blood flow, and lower levothyroxine requirements over nine months. You can read that post here: red light therapy and your thyroid: the research. I'm not going to repeat all of that here.

What I will say in this context is that the mechanism being proposed, supporting mitochondrial function in a gland that's under chronic immune stress, makes particular sense when you layer in the Norwegian picture. A thyroid gland that's dealing with suboptimal selenium, low vitamin D through winter, and active autoimmune attack is a gland under a lot of compounding pressure. Whether red light therapy makes a meaningful difference in that context specifically, nobody can say with certainty from the current research. But the theoretical basis for it doing something useful is stronger here than in a population with adequate selenium and vitamin D year-round.

What I would be much more confident saying is this: if you're in Norway, suspect Hashimoto's, and haven't yet sorted your vitamin D supplementation through winter and looked properly at your selenium intake, those things come first. They have stronger evidence bases, they're cheap, and they're relevant regardless of anything else you do. Red light therapy is an adjunct, not a foundation.

Practically, if you're doing this

If you do want to use red light therapy alongside whatever your doctor has you on, the practical approach is short sessions, a few times a week, with a smaller device positioned so the front of the neck is exposed rather than a large full-body panel at distance. The thyroid is sensitive to both too little and too much of almost everything, the biphasic dose response applies here more than anywhere. I'd start conservative and stay there.

For smaller devices suited to neck placement, the portable and specialist devices collection has the options I've tested. And if you want to talk through what makes sense given your specific bloods, message me. Not a doctor, won't pretend otherwise, but I know the research and I'm happy to think through it with you.

Disclaimer: This post is for educational purposes only and does not constitute medical advice. Thyroid conditions including Hashimoto's thyroiditis require diagnosis and ongoing management by a qualified healthcare professional. Never stop, start or adjust thyroid medication without medical supervision. Speak with your doctor before starting any new health practice if you have a thyroid condition.

Frequently Asked Questions

Why is Hashimoto's so often missed in Norway?

Standard thyroid testing in Norway typically measures TSH alone. In Hashimoto's, TSH can remain within the normal reference range for years while thyroid antibodies are elevated and the autoimmune process is active. Asking specifically for free T3, free T4, TPOAb and TgAb gives a more complete picture. Additionally, low selenium levels in Norwegian soil and widespread vitamin D deficiency through winter are both associated with higher risk and worse outcomes in autoimmune thyroid conditions.

Does selenium help with Hashimoto's?

Selenium is essential for thyroid function, particularly for converting T4 to the active form T3, and the thyroid contains a high concentration of it relative to other organs. Low selenium is associated with increased risk of autoimmune thyroid conditions and higher antibody levels in people who already have Hashimoto's. Norwegian soil selenium levels are relatively low, and intake from diet varies considerably. It's worth discussing selenium status with your doctor if you have Hashimoto's or suspect you might.

Can red light therapy help with Hashimoto's in addition to medication?

A small number of peer-reviewed studies from Brazil found low-level laser therapy applied over the thyroid was associated with reduced antibody levels and lower levothyroxine requirements over nine months in people with Hashimoto's-induced hypothyroidism. This is early research with small sample sizes. It is not a replacement for medication, and any changes to medication should involve your doctor and regular blood testing. The research is covered in more detail here: red light therapy and your thyroid: the research.

What tests should I ask for if I suspect Hashimoto's?

Beyond TSH, the most useful tests for Hashimoto's specifically are free T3, free T4, TPOAb (thyroid peroxidase antibodies) and TgAb (thyroglobulin antibodies). Elevated antibodies with normal TSH indicate the autoimmune process is active. These can be requested from your GP, though not all will order them without specific reason. If you're getting consistent symptoms and normal TSH, asking for the full panel by name is a reasonable next step.

Hvorfor blir Hashimotos så ofte oversett i Norge?

Standard skjoldbruskkjerteltesting i Norge måler vanligvis bare TSH. Ved Hashimotos kan TSH ligge innenfor normalområdet i årevis mens antistoffene er forhøyede og den autoimmune prosessen er aktiv. Å be spesifikt om fritt T3, fritt T4, TPOAb og TgAb gir et mer fullstendig bilde. I tillegg er lavt seleninnhold i norsk jord og utbredt D-vitaminmangel gjennom vinteren begge knyttet til høyere risiko og dårligere forløp ved autoimmune skjoldbruskkjerteltilstander.

References

Höfling DB, Chavantes MC, Juliano AG, et al. Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial. Lasers in Medical Science. 2013. https://pubmed.ncbi.nlm.nih.gov/22718472/

Höfling DB, Chavantes MC, Juliano AG, et al. Assessment of the effects of low-level laser therapy on the thyroid vascularization of patients with autoimmune hypothyroidism by colour Doppler ultrasound. ISRN Endocrinology. 2012. https://pmc.ncbi.nlm.nih.gov/articles/PMC3534372/

Höfling DB, Chavantes MC, Buchpiguel CA, et al. Safety and efficacy of low-level laser therapy in autoimmune thyroiditis: long-term follow-up study. International Journal of Endocrinology. 2018. https://pmc.ncbi.nlm.nih.gov/articles/PMC6247385/