We found personally and have observed consensus that aged 40+, systems start to change and what could be taken for granted often requires new techniques and/or a bit more effort. For example supplementing NAD+ will likely be pretty interesting aged 40+ and of little interest before then.
Accessing medical information and using wearable technology is of interest to some more than others and in general we see more activity for those aged 40 – 70. For example those familiar with using technology to cost-effectively access specialized services at a convenient time and location (whether banking, flights and shopping or medical information) might be more interested in a medtech app than those who first need to wrap their head around how to use a smartphone.
But as with everything, it all depends e.g. a healthy fit 25 year old female is discovering things like VitB will fix a REM sleep deficiency. We also have clients in their 80s who are using the Oura to work on quality of sleep, memory and cognition. If the interest is there, age is no barrier.