Shilajit
Shilajit is a natural substance that develops from the breakdown of plants and organic material. It’s a blackish-brown, tar-like substance that’s primarily found in the Himalayas. Shilajit is used in ancient Ayurvedic medicine to promote overall health and wellness. 
Researchers have studied shilajit as a possible way to improve infertility and boost male hormone levels. One study found that middle-aged men who took Shilajit supplements for 90 days saw an increase in total testosterone levels
An older study assessed the impacts of Shilajit on men with a low sperm count It suggests the supplements help increase testosterone, follicle-stimulating hormone (FSH), sperm count, and sperm motility.