Thank you for criticism of the article touching on various aspects. Even though I agree on the importance of scientific rigor, as this is a Medium story (not a scientific paper), I had to write in a style for my audience reflecting my personal experience. There is substantial evidence on the effects of cold exposure. Even though Wim Hof sensationalized the cold exposure he also contributed to research significantly. As you wisely point out there are many more factors which scientist are exploring. If you prepare a literature review on the topic and publish it on Medium, please feel free to tag me as I have strong interest about the research in the field. I appreciate your time and valuable feedback.