Bio Impedance Analysis is a noninvasive test that requires no doctor, no lab, and no cost other than the initial outlay for the machine, which
estimates body composition and in particular body fat. The simple calculations give lean body mass, % body fat, etc. There are nice numbers that will give participants good feedback on healthy living, which alone is worthwhile, but are not validated Biomarkers for Longevity. However standing on one of these scales that is wireless connected by ant+ technology gives data on the cell phone that can be sent to a database via cell phone. This is an effortless way to collect daily data points from volunteers. What is even more useful is the more complex calculations that can be derived from Bio Impedance Testing such as
phase angle, which is resistance. Phase angle has been validated in many published studies as a Biomarker for both Aging and for health/disease. The machines for measuring phase angle are a little more complex, but home units are available for purchase online for 100-300$.