Brief report: circadian melatonin, thyroid-stimulating hormone, prolactin, and cortisol levels in serum of young adults with autism.

Doctors drew blood from autistic young adults every few hours for a full day.

They checked melatonin, cortisol, thyroid, and prolactin to map each hormone’s daily rhythm.

The design was a small case series with no control group.

Melatonin rhythms looked flat or shifted in every participant.

Cortisol, thyroid, and prolactin also showed odd timing, but melatonin was the clearest signal.

The authors suggest these blunted cycles could serve as future biomarkers.

Nasr et al. (2000) and Mutluer et al. (2016) later asked parents about sleep. Parents reported more bedtime struggles and longer sleep latency in autistic children, matching the flat melatonin picture seen here.

Lemons et al. (2015) went deeper, finding that autistic children with sleep-onset delay often carry gene variants in ASMT and CYP1A2, the very enzymes that make and break down melatonin. Together the three studies move from ‘hormones look odd’ to ‘genes may explain why’.

Durand et al. (1990) used a similar round-the-clock blood method but tested growth hormone. They also saw timing problems, showing that multiple hormonal clocks can be off in autism.

If a client’s sleep is erratic, request a sleep diary first. If patterns remain unclear, discuss a low-dose melatonin trial with the physician. You can also suggest dim-light melatonin onset testing to pinpoint circadian phase. Tracking bedtime, wake time, and daytime behavior before and after the supplement gives you data to fine-tune intervention.