https://www.melanixhealth.com/notes/ Methodology, observations, and limits of a computational dermatology engine. en https://www.melanixhealth.com/notes/08/ https://www.melanixhealth.com/notes/does-skin-type-change-over-time/ Sun, 21 Jun 2026 00:00:00 +0000 A methodology note. Why the oily-or-dry label you were assigned is a snapshot of a moving target, what makes skin shift across the day, the month, the season, and the decade, and why the honest read follows the state you are in now rather than a fixed type. https://www.melanixhealth.com/notes/07/ https://www.melanixhealth.com/notes/how-long-does-skincare-take-to-work/ Fri, 19 Jun 2026 00:00:00 +0000 A methodology note. Why the skin you see today is a slow readout of the past several weeks, why the newest change in your routine is the least likely explanation for what you see, and what that lag means for reading skin honestly. https://www.melanixhealth.com/notes/06/ https://www.melanixhealth.com/notes/is-one-bad-skin-day-normal/ Mon, 15 Jun 2026 00:00:00 +0000 A limits note. Why a single day's read of your skin cannot tell a real change from normal fluctuation, what the noise is actually made of, and the hard limit that places on any tracker, Mela included. https://www.melanixhealth.com/notes/05/ https://www.melanixhealth.com/notes/is-it-purging-or-irritation/ Fri, 12 Jun 2026 00:00:00 +0000 A category critique with the evidence. Why "purging" has become the default explanation for almost any early breakout, when the one defensible version of it is narrow and the popular version cannot be told apart from plain irritation in the two weeks people use to decide. https://www.melanixhealth.com/notes/04/ https://www.melanixhealth.com/notes/is-it-your-skincare-or-the-season/ Wed, 10 Jun 2026 00:00:00 +0000 A category critique with the evidence. Why the most common "my routine stopped working this fall" story is, more often than not, a seasonal shift wearing the timing of whatever product changed, and what it takes to tell the two apart. https://www.melanixhealth.com/notes/03/ https://www.melanixhealth.com/notes/is-it-your-serum-or-your-cycle/ Wed, 03 Jun 2026 00:00:00 +0000 A category critique with the evidence. Why the most common "my new product broke me out" story is, for roughly half of women, a premenstrual flare wearing the serum's timing, and what it takes to tell the two apart. https://www.melanixhealth.com/notes/02/ https://www.melanixhealth.com/notes/the-wrong-measurement-problem/ Thu, 28 May 2026 00:00:00 +0000 A literature review and category critique. Six layers of skin physiology the basic-science evidence treats as the signal, and what consumer skincare is failing to operationalize from them. https://www.melanixhealth.com/notes/01/ https://www.melanixhealth.com/notes/how-mela-sorts-cause-from-coincidence/ Tue, 26 May 2026 00:00:00 +0000 A worked example: causal-discovery procedure walked through synthetic 30-day skin data with a known ground-truth edge, showing where the procedure recovered the truth, where it found a spurious pattern, and how the hedging in user-facing copy is calibrated.