My HormonologyErica, a Hormonology newsletter subscriber, asks: “As someone who dyes her hair every four weeks, I was wondering—is there a best week of my monthly cycle to touch up my roots?”

My answer: I’m basing my response not on hormone research, per se, but on what I’ve found works for me as a hormone cycling woman who also dyes her hair once per month. It may work for you, too: I wait till the end of my Week 3 to touch up my roots. The reason? I like to gussy myself up a little for my premenstrual Week 4 to counter the downward-spiraling self-confidence that comes from plunging estrogen and testosterone. If I see a thicket of grey growth in Week 4, it just bums me out more than it would any other week. What’s more, timing my root touch-up for this phase of my cycle gives me three good weeks of coverage, which means my hair will look great all throughout my rising estrogen/testosterone Week 1 and Week 2 when these climbing hormones are pushing me to get out of the house and socialize. By Week 3, I know that rising progesterone and lower levels of estrogen and testosterone mean I’ll be spending more time indoors and not around as many people, so having root growth isn’t such a big deal since fewer folks will see it!