One year on testosterone: what trans men should actually expect

What did @solsimbulan actually say?

Sol documented their voice monthly for a full year on testosterone, recording brief audio clips at each milestone: "Hi, my name is Sol and this is my voice" followed by the month count. The video is essentially a longitudinal self-recording of voice change, not a series of medical claims. There are no dosage recommendations, no product endorsements, and no promises about what testosterone will do for anyone else. The implicit claim is that testosterone caused progressive, audible voice deepening over 12 months.

That is a reasonable implicit claim. The format is honest: one person, one voice, one timeline. It does not overpromise. The caption adds a personal note about pride and judgment, which is not a medical statement at all.

Does the science back this up?

Yes, broadly. Voice deepening is one of the most consistently documented physical effects of testosterone in transgender men and is driven by laryngeal growth and changes to vocal fold mass and tension. The timeline Sol shows, gradual change across 12 months, is consistent with what the literature reports.

Azul et al. (2017, Journal of Speech, Language, and Hearing Research) found that fundamental frequency (the acoustic measure of pitch) dropped significantly within the first few months of testosterone therapy and continued to change for up to two years. Damrose (2009, Journal of Voice) confirmed that laryngeal changes in trans men are real, measurable, and comparable in some respects to pubertal voice change in adolescent males, though the process differs physiologically. A 2021 systematic review by Riding et al. in Transgender Health found that most voice changes occur within 3 to 6 months but refinement continues well past year one. Sol's recordings appear consistent with this trajectory, with early noticeable shift and continued change through month 12.

What did they get wrong (or right)?

Honestly, Sol got more right than wrong, mostly by not saying much at all. The restraint here is worth noting. There are no claims that testosterone will produce a specific result, no timeline promises to viewers, and no medical advice. That is genuinely responsible content for a platform where health misinformation spreads fast.

What is missing, and this matters, is individual variability. Voice change on testosterone is highly unpredictable. Starting pitch, age, genetics, dose, and even smoking history all influence outcomes. Some trans men experience significant deepening within weeks; others take two or more years and do not reach a pitch they are satisfied with. T'Sjoen et al. (2019, Endocrine Reviews) noted that while virilization is expected, the degree varies considerably between individuals. A viewer watching Sol's video might assume their own voice will follow the same curve. That assumption would be unfounded. The video does nothing to set that expectation correctly, which is a gap, not a lie, but a meaningful one.

What should you actually know?

Voice change is real, measurable, and expected on testosterone therapy, but it is not guaranteed to follow any particular person's timeline or endpoint. Sol's one-year arc is one data point, not a standard. A few things worth knowing if you are considering or currently on testosterone for any indication:

• Laryngeal changes from testosterone are generally considered irreversible. If voice change is a concern, that matters before starting.
• The 3 to 6 month window is when most people notice the most dramatic shift, but "settling" of the voice can take two or more years (Riding et al., 2021, Transgender Health).
• Testosterone does not work the same way in trans men as in cisgender men with hypogonadism. The baseline hormonal environment is different, and clinicians should be monitoring accordingly.
• If you are using testosterone for any purpose, voice changes are a side effect to discuss with your prescriber, especially if you are a professional voice user (singer, broadcaster, teacher).
• Self-recorded voice timelines like Sol's are useful for personal documentation but are not a substitute for acoustic analysis by a speech-language pathologist if voice is a clinical concern.

Bottom line

This video is a personal milestone, not a medical tutorial. Sol is not prescribing anything or making claims about outcomes. The implicit message, that testosterone changes the voice progressively over a year, is accurate. The gap is that no single person's timeline is anyone else's roadmap. Watch it as someone's story. Do not use it as a medical reference.