Hi Karen,

The most common way is to inhibit 5α-reductase, the enzyme that makes DHT (dihydrotestosterone) from testosterone. Anti-androgens inhibit aromatase.

My current list of anti-androgens is:

hops cones
spearmint tea (peppermint is more estrogenic)
saw palmetto berry
stinging nettle root
pumpkin seed oil
borage seed oil
Zinc < 80 mg daily
vitamin B6
azelaic acid (in rye, barley grass, whole grain cereals)
Secoisolariciresinol diglycoside (SDG), the main lignan in flax (linseed)
β-Sitosterol
Java tea (orthosiphon extract)
pygeum bark
wild yam (because it contains β-sitosterol)

Muscle growth receives the androgen signal from testosterone directly, not from DHT. So avoid working out your arms and shoulders.