If you actually watch the video, they are not uncritical regarding the idea of lengthening telomeres due to a hypothetical cancer risk. Then they point to two

If you actually watch the video, they are not uncritical regarding the idea of lengthening telomeres due to a hypothetical cancer risk. Then they point to two studies that show that Omega 3 and Vitamin D lenghtened or maintained telomere length against control groups. The benefits of sauna are supported in a similar fashion. You can argue that the studies are of poor quality, but that is true for most studies regarding medicine and especially nutrition. You gotta take a chance either way.