Hello Sonia, it does not appear that Dr. Greger has made a video about the pill. As this is a site devoted to nutrition information, this important question is a bit out of traditional scope for Nutritionfacts. I do very much value today’s videos, and would encourage you to view Dr. G’s other videos in this series. I will do a search on “evidence base safety of contraceptives” and get back to you a bit later with some references you can read, and evaluate for yourself. Stay tuned! And thank you for your question.
The vitamin D endocrine system. In this system, the biologically inactive vitamin D 3 is activated, first in the liver to produce 25-hydroxyvitamin D 3 [25(OH)D 3 ], and the endocrine gland (the kidney) converts it to the hormones 1α,25-dihydroxyvitamin D 3 [1α,25(OH) 2 D 3 ] and 24 R ,25-dihydroxyvitamin D 3 [24 R ,25(OH) 2 D 3 ]. Researchers have identified ≥36 target organs, defined by the presence of the vitamin D receptor (VDR), which is the receptor for the steroid hormone 1α,25(OH) 2 D 3 ; see Table 1 for a list of these target organs. Table 2 lists the 10 extrarenal tissues that investigators have shown possess the 1α-hydroxylase, the enzyme that converts 25(OH)D 3 to the steroid hormone 1α,25(OH) 2 D 3 . Pi, inorganic phosphate.
Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.