There are too many publications to name that demonstrate the importance of 5α-reduced steroids and DHT in mammalian physiology. Are they essential for existing? No, but I guess by that logic, eyes, fingers, a functioning dick, etc. are not essential for existence either. Just because some people can live without something and can tolerate it better than others doesn't mean that it's optimal to physiologically exist that way.Any citations for that, before you exhort the hordes to destroy books? We really don't know what controls mood vel non and the anti-finasteride people are usually bald and ornery.