If your thyroid gland produces not enough thyroid hormones, you have thyroid deficiency, medically known as hypothyroidism. The most common causes of hypothyroidism are iodine deficiency and, where iodine deficiency is uncommon, Hashimoto’s disease, an autoimmune disease that progressively destroys your thyroid gland. 7 Thyroid deficiency slows down your metabolism Poor thyroid function 5 is often associated with reduced libido and erectile dysfunction; furthermore it has an adverse effect on the form and structure of sperm – all of which can give rise to infertility.
Erythropoietin (EPO): A 165 amino acid glycoprotein hormone (glycoproteins consist of several sugar molecules linked with a protein molecule). EPO stimulates erythrocyte (red blood cell) production in the bone marrow, boosting the blood's ability to carry oxygen. Studies have shown that significant amounts of EPO resist digestion and survive to reach receptors in the intestinal tract. One raw milk-drinking athlete was wrongly accused of blood-doping, so there's at least anecdotal evidence of EPO's activity in our systems!