Three studies.
Three different questions.

What was tested, what changed, and what the findings cannot tell us.

A large review found a useful signal for pattern hair loss, with much less evidence for other causes.

A trial with 160 participants shows why combined results can tell a different story from separate treatment groups.

One side of the scalp received light and the other sham treatment. Here is what changed and why the comparison matters.

Three studies.Three different questions.