1. Preface
One of the most popular articles of my blog has been about the therapeutic effects red and near-infrared light. An edited version the article has also been published at Perfect Health Diet blog.
Hundreds of studies have shown that red or near-infrared light can be used in the treatment of various medical conditions. According to some of the studies, it could possibly...
- reduce pain in various conditions
- prevent hair loss
- improve exercise performance and muscle recovery
- increase the benefits of exercise: muscle gain and fat loss
- reduce the complications of cancer treatments
- improve vision in patients with age-related macular degeneration
The treatment is officially called photobiomodulation (PBM). It was previously called low-level laser therapy (LLLT), because most of the research was conducted with laser light sources. Nowadays it is considered proven that the positive effects of red and near-infrared light do not require lasers, and therefore many photobiomodulation research groups are currently using LEDs.
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| PBM treatment often looks like this. However, the beam size varies a lot (1mm2 - 32cm2) in different studies. (Image source: SpinalStenosis) |
Photobiomodulation (PBM) is based on the research showing that red light and near-infrared radiation can boost cellular energy metabolism by activating the enzyme complex called cytochrome c oxidase. This energy-boosting effect can apparently protect tissues from stress and inflammation.
2. PBM and hypothyroidism
Many interesting results have been published regarding the treatment of hypothyroidism with PBM. Here's my short summary of the results.
1) In a Brazilian pilot study (2010), 47% of the hypothyroid patients receiving 10 treatment sessions of PBM with near-infrared laser light maintained normal thyroid hormone levels without thyroid medication (levothyroxine; LT4) at the end of the 9-month follow-up.
Other benefits were also noted: TPOAb levels decreased by 39%, echogenicity index (EI) increased by 22% and normalization of thyroid volume was noted in three of the seven patients with abnormal thyroid volume.
1) In a Brazilian pilot study (2010), 47% of the hypothyroid patients receiving 10 treatment sessions of PBM with near-infrared laser light maintained normal thyroid hormone levels without thyroid medication (levothyroxine; LT4) at the end of the 9-month follow-up.
Other benefits were also noted: TPOAb levels decreased by 39%, echogenicity index (EI) increased by 22% and normalization of thyroid volume was noted in three of the seven patients with abnormal thyroid volume.
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| (Höfling et al. 2010) |
2) In a Brazilian randomized controlled trial (2013), 48% of the hypothyroid patients receiving 10 sessions of PBM maintained normal thyroid hormone levels without thyroid medication at the end of the 9-month follow-up.
Other benefits were also noted: TPOAb levels decreased by 49%, echogenicity index (EI) increased by 19% and normalization of thyroid volume was noted in five of the seven patients with abnormal thyroid volume. Thyroid vascularization was corrected in 16 of 22 patients who had abnormal vascularization at the baseline.
Other benefits were also noted: TPOAb levels decreased by 49%, echogenicity index (EI) increased by 19% and normalization of thyroid volume was noted in five of the seven patients with abnormal thyroid volume. Thyroid vascularization was corrected in 16 of 22 patients who had abnormal vascularization at the baseline.
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| LT4 = levothyroxine ; L-group = PBM/LLLT group ; P-group = placebo group (Höfling et al. 2013) |
3) A Turkish randomized study (2020) recruited 350 patients found that six sessions of PBM with near-infrared light (850 nm) during three consecutive days was associated with 50% decrease in levothyroxine (LT4) medication usage, 53% increase in T3 levels and 73% decrease in TPOAb levels three months after the PBM treatments. According to the report, 28.5% of the patients had also completely stopped using the LT4 medication.
4) In an Ukrainian dissertation study by Viktor Dubovik (2003), it was concluded that PBM can decrease medication requirements by 50-75% in people with postsurgical hypothyroidism. Antibodies for Tg and TPO were decreased after the treatment.
5) Another Ukrainian study by Yulia Buldygina (2002) concluded that PBM might be beneficial for hypertrophic forms of autoimmune thyroiditis. In this study, they utilized a red light (633 and 850 nm) from a laser device.
In this long-term study, they treated patients with euthyroid, subclinically hypothyroid and clinically hypothyroid hormone levels. In all groups, the decrease in TSH and TgAb was remarkable.
Laser therapy allows in 92% of patients delay the development of the pathological process, and 40% - to reach its full or partial regression or prevent progression to hypothyroidism and eliminate its initial manifestations, as evidenced by normalization of thyroid stimulating hormone. [...]
Laser therapy can be used as an independent method of treatment of hypertrophic form of autoimmune thyroiditis or as an additional method that increases the effectiveness of traditional drug therapy." [Translated from the original text by Google Translate]
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| Consecutive PBM treatments were able to decrease TSH levels in (1) euthyroid, (2) subclinically hypothyroid and (3) overtly hypothyroid patients with hypertrophic form of autoimmune thyroiditis. The most pronounced effect was seen after 4 courses (each course included 10-15 treatment sessions). |
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| Consecutive PBM treatments decreased thyroid gland volume (left side and right side) in euthyroid patients with hypertrophic form of autoimmune thyroiditis. |
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| During this ~2-year study, the TgAb levels of the patients decreased dramatically. [Image translated/edited by me] |
6) Ukrainian study by Katerina Misura (2006) showed that PBM can improve the treatment results in hypothyroid patients who also suffer from cardiovascular disease. These patients don't usually take adequate amounts of oral thyroxine, because of the possibility of severe cardiovascular symptoms.
Both groups received various drugs including levothyroxine, lovastatin and aspirin, but intervention group also received PBM treatment. In this group, significant improvements in thyroid hormone and cholesterol levels were observed.
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| In PBM group, TSH decreased 53% and T4 increased 95% in 3 months. In the control group, the hormone concentrations remained unchanged. |
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| In PBM group (n=27), total cholesterol decreased from 8.23 to 6.09 in 3 months. In the control group, the decrease was much less pronounced (8.20 -> 7.67). |
7) In a Russian dissertation study (2010), 17% of the hypothyroid patients receiving PBM on the thyroid area could discontinue thyroid medication, and 38% could decrease the dose by 25-50µg.
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| Groups 2 and 4 received PBM on their thyroid glands, while group 5 served as a control group. This table shows PBM's effect on thyroid antibodies (TPO, Tg). |
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| Some symptoms decreased after treating hypothyroid patients with PBM: Discomfort in the region of thyroid gland, dry skin, constipation, lethargy/drowsiness and fatigue. |
8) In an Russian report (2014), the treatment of 347 subclinically hypothyroid women was described.
Their baseline TSH averaged at 9.1 mIU/L, but after ten sessions of PBM, the TSH was normalized in 337 (97%) of these women. Their TSH averaged at 2.2 mIU/L after the PBM treatments.
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| The paper says: "The infrared spectrum of the laser radiation is effective and safe treatment for patients with SH (subclinical hypothyroidism) due to autoimmune thyroiditis[...] In our opinion, it is the method of choice in the treatment of the pathology, especially in the elderly." (Puzin 2014) |
9) A Russian study by Alexander Poljakov (1997) includes some data of chronic autoimmune thyroiditis patients who underwent a thyroid surgery.
Photobiomodulation (PBM) with near-infrared light (890 nm) from a laser source was found to improve thyroid hormone levels of these patients. It was also mentioned that the patients treated with PBM require half as much thyroxine as usually.
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| In the laser group, T3 and T4 levels were significantly increased at 6 months and 5 years after the operation, while the levels tended to decrease in the "standard treatment" group. |
10) Ukrainian researchers also conducted an animal study, in which they they induced experimental autoimmune thyroiditis to rabbits (n=40). Apparently, photobiomodulation (PBM) reversed most of the thyroiditis-associated changes to the thyroid tissue.
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| KG = control group; EAIT = experimental autoimmune thyroiditis; LT = low-level laser therapy; Klein index = Average diameter of 100 follicles |
(Note: Since most of the reports cited are in Russian/Ukrainian language, I hope that I'll find a native person to proofread and confirm my summaries. I'm only half-Russian, and I cannot read these languages perfectly.)
3. Conclusions
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| (Höfling et al. 2013) |
I would say these results are very impressive. I'm not aware of any other treatment that could improve several markers related to hypothyroidism and even allow some patients to discontinue their thyroid medication. This would make PBM (previously "LLLT") a very appealing future treatment to hypothyroid patients.
Since ~400 papers on PBM are being published annually, I guess that it won't take many years until we know much more about possibilities in the use of light in the treatment of hypothyroidism and many other diseases.
4. Addendum: How can we apply these results in real life?
These photobiomodulation (PBM) studies were all conducted with a laser device (Thera Lase in Brazil; Mustang 2000 in Russia/Ukraine). The usage of lasers has been very common in PBM, which was previously called low-level laser (light) therapy (LLLT).
However, the current evidence suggests that laser lights are not required for photobiomodulation. in other words, LED lights can be used for photobiomodulation as well. Preliminary evidence also suggests that even the typical sources of broadband light (eg. halogen lamps, incandescent lamps, heat lamps) might work for photobiomodulation (Heiskanen&Hamblin 2018).
Actually, 110 years ago there were some books that recommended the light of incandescent bulbs in the treatment of various diseases such as obesity, diabetes, balding and chronic fatigue. The authors of those books understood it's the red/infrared part of the light that is responsible for these beneficial health effects.
I would assume that the main reason why the researchers have favoured laser in the past, is the fact that it is easy to control several dose parameters accurately when you are using laser light instead of light bulbs: wavelength, power output, power density, spot size, pulsing, total energy per spot...
As a conclusion, I would say that it's possible that red and near-infrared LEDs and even ordinary incandescent/heat/halogen bulbs could have these beneficial effects since they emit the right wavelengths (red light and near-infrared). However, as I've explained in my comprehensive article about PBM, I think one needs to be careful about the dosing, as photobiomodulation is characterized by the biphasic dose response, where either too little or too much light might be ineffective.
Since ~400 papers on PBM are being published annually, I guess that it won't take many years until we know much more about possibilities in the use of light in the treatment of hypothyroidism and many other diseases.
4. Addendum: How can we apply these results in real life?
These photobiomodulation (PBM) studies were all conducted with a laser device (Thera Lase in Brazil; Mustang 2000 in Russia/Ukraine). The usage of lasers has been very common in PBM, which was previously called low-level laser (light) therapy (LLLT).
However, the current evidence suggests that laser lights are not required for photobiomodulation. in other words, LED lights can be used for photobiomodulation as well. Preliminary evidence also suggests that even the typical sources of broadband light (eg. halogen lamps, incandescent lamps, heat lamps) might work for photobiomodulation (Heiskanen&Hamblin 2018).
Actually, 110 years ago there were some books that recommended the light of incandescent bulbs in the treatment of various diseases such as obesity, diabetes, balding and chronic fatigue. The authors of those books understood it's the red/infrared part of the light that is responsible for these beneficial health effects.
I would assume that the main reason why the researchers have favoured laser in the past, is the fact that it is easy to control several dose parameters accurately when you are using laser light instead of light bulbs: wavelength, power output, power density, spot size, pulsing, total energy per spot...
As a conclusion, I would say that it's possible that red and near-infrared LEDs and even ordinary incandescent/heat/halogen bulbs could have these beneficial effects since they emit the right wavelengths (red light and near-infrared). However, as I've explained in my comprehensive article about PBM, I think one needs to be careful about the dosing, as photobiomodulation is characterized by the biphasic dose response, where either too little or too much light might be ineffective.
5. References
[1] Lasers Surg Med. 2010 Aug;42(6):589-96. Low-level laser therapy in chronic autoimmune thyroiditis: a pilot study. Höfling DB, Chavantes MC, Juliano AG, Cerri GG, Romão R, Yoshimura EM, Chammas MC. http://www.ncbi.nlm.nih.gov/pubmed/20662037
[2] Lasers Med Sci. 2013 May;28(3):743-53. Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial. Höfling DB, Chavantes MC, Juliano AG, Cerri GG, Knobel M, Yoshimura EM, Chammas MC. http://www.ncbi.nlm.nih.gov/pubmed/22718472
ISRN Endocrinol. 2012;2012:126720. Assessment of the effects of low-level laser therapy on the thyroid vascularization of patients with autoimmune hypothyroidism by color Doppler ultrasound. Höfling DB, Chavantes MC, Juliano AG, Cerri GG, Knobel M, Yoshimura EM, Chammas MC.
[3] Photobiomodul Photomed Laser Surg. 2020 Mar 18. Impact of Photobiomodulation on T3/T4 Ratio and Quality of Life in Hashimoto Thyroiditis. Ercetin C, Sahbaz NA, Acar S, Tutal F, Erbil Y. https://www.ncbi.nlm.nih.gov/pubmed/32186976
[4] Dubovik V. The postoperative rehabilitation of the autoimmune thyroiditis patients with the use of lowintensive laser radiation. http://librar.org.ua/sections_load.php?s=medicine&id=5298 [I also paid for an Ukrainian translator to make an English copy of the Ukrainian article, so I have an English PDF]
Gopkalova I, Dubovik V, Danilevsky V. Effectiveness of using laserotherapy in the treatment of autoimmune thyreoiditis. CAOL 2003. Institute of Endocrine Pathology Problems of Academy of Medical Sciences of Ukraine (IEPP)
[5] Buldygina Y. Possibilities of low-intensive laser radiation in treatment of hypertrophic form of autoimmune thyroiditis. – Manuscript. Dissertation for degree of candidate of medical science by speciality 14.01.14 – endocrinology. – V.P. Komissarenko Institute of Endocrinology and Metabolism of AMS Ukraine, Kiev, 2002.
[6] Misura E.V. A complex method for treating patients with autoimmune thyroiditis in presence of hypothyroidism and accompanying coronary disease. - Manuscript. The dissertation competing for a scientific degree of Candidate of Medical Science in specialty 14.01.14 – Endocrinology. V. Danilevsky Institute of Endocrine Pathology Problems of the Academy of Medical Sciences of Ukraine, Kharkov, 2006.
[7] Вера Александровна Кривова: Неинвазивная гемолазеротерапия в системе реабилитации больных аутоиммунным тиреодитом (Диссертация, 2010) [A Russian dissertation] http://www.dissercat.com/content/neinvazivnaya-gemolazeroterapiya-v-sisteme-reabilitatsii-bolnykh-autoimmunnym-tireoditom
[8] Д.А. ПУЗИН: Лазеротерапия в лечении субклинического гипотиреоза различной этиологии (2014) http://www.medprem.ru/rimg/files/rekomendacii_po_primeneniya.pdf
[9] Поляков АВ. Применение низкоинтенсивного лазерного излучения в комплексном лечении хронического аутоиммунного тиреоидита (1997) http://medical-diss.com/medicina/primenenie-nizkointensivnogo-lazernogo-izlucheniya-v-kompleksnom-lechenii-hronicheskogo-autoimmunnogo-tireoidita
[10] Dubovik V. The postoperative rehabilitation of the autoimmune thyroiditis patients with the use of lowintensive laser radiation. http://librar.org.ua/sections_load.php?s=medicine&id=5298
Gopkalova I, Dubovik V. Reparative regeneration processes of thyroid gland and timus at experimental autoimmune thyroiditis after laserotherapy. (2010) http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5634184
[2] Lasers Med Sci. 2013 May;28(3):743-53. Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial. Höfling DB, Chavantes MC, Juliano AG, Cerri GG, Knobel M, Yoshimura EM, Chammas MC. http://www.ncbi.nlm.nih.gov/pubmed/22718472
ISRN Endocrinol. 2012;2012:126720. Assessment of the effects of low-level laser therapy on the thyroid vascularization of patients with autoimmune hypothyroidism by color Doppler ultrasound. Höfling DB, Chavantes MC, Juliano AG, Cerri GG, Knobel M, Yoshimura EM, Chammas MC.
[3] Photobiomodul Photomed Laser Surg. 2020 Mar 18. Impact of Photobiomodulation on T3/T4 Ratio and Quality of Life in Hashimoto Thyroiditis. Ercetin C, Sahbaz NA, Acar S, Tutal F, Erbil Y. https://www.ncbi.nlm.nih.gov/pubmed/32186976
[4] Dubovik V. The postoperative rehabilitation of the autoimmune thyroiditis patients with the use of lowintensive laser radiation. http://librar.org.ua/sections_load.php?s=medicine&id=5298 [I also paid for an Ukrainian translator to make an English copy of the Ukrainian article, so I have an English PDF]
Gopkalova I, Dubovik V, Danilevsky V. Effectiveness of using laserotherapy in the treatment of autoimmune thyreoiditis. CAOL 2003. Institute of Endocrine Pathology Problems of Academy of Medical Sciences of Ukraine (IEPP)
[5] Buldygina Y. Possibilities of low-intensive laser radiation in treatment of hypertrophic form of autoimmune thyroiditis. – Manuscript. Dissertation for degree of candidate of medical science by speciality 14.01.14 – endocrinology. – V.P. Komissarenko Institute of Endocrinology and Metabolism of AMS Ukraine, Kiev, 2002.
[6] Misura E.V. A complex method for treating patients with autoimmune thyroiditis in presence of hypothyroidism and accompanying coronary disease. - Manuscript. The dissertation competing for a scientific degree of Candidate of Medical Science in specialty 14.01.14 – Endocrinology. V. Danilevsky Institute of Endocrine Pathology Problems of the Academy of Medical Sciences of Ukraine, Kharkov, 2006.
[7] Вера Александровна Кривова: Неинвазивная гемолазеротерапия в системе реабилитации больных аутоиммунным тиреодитом (Диссертация, 2010) [A Russian dissertation] http://www.dissercat.com/content/neinvazivnaya-gemolazeroterapiya-v-sisteme-reabilitatsii-bolnykh-autoimmunnym-tireoditom
[8] Д.А. ПУЗИН: Лазеротерапия в лечении субклинического гипотиреоза различной этиологии (2014) http://www.medprem.ru/rimg/files/rekomendacii_po_primeneniya.pdf
[9] Поляков АВ. Применение низкоинтенсивного лазерного излучения в комплексном лечении хронического аутоиммунного тиреоидита (1997) http://medical-diss.com/medicina/primenenie-nizkointensivnogo-lazernogo-izlucheniya-v-kompleksnom-lechenii-hronicheskogo-autoimmunnogo-tireoidita
[10] Dubovik V. The postoperative rehabilitation of the autoimmune thyroiditis patients with the use of lowintensive laser radiation. http://librar.org.ua/sections_load.php?s=medicine&id=5298
Gopkalova I, Dubovik V. Reparative regeneration processes of thyroid gland and timus at experimental autoimmune thyroiditis after laserotherapy. (2010) http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5634184
