23/02/2026
I've been told soy will destroy my testosterone for years.
(here's what the science actually says)
Growing up lifting weights, everyone warned me:
"Don't touch soy, bro. It'll make you grow man b***s."
"Soy has estrogen in it. You'll lose all your gains."
"Real men don't eat tofu."
And for a long time, I believed it.
But then I actually looked at the research.
Here's what I found:
Soy contains isoflavones - phytoestrogens that can bind to estrogen receptors.
Sounds scary, right?
That's where the feminizing concerns came from.
But here's the thing:
A meta-analysis of 41 studies found NO effect of soy consumption on men's hormone levels (Viscardi et al., 2025).
No effect at all.
Another meta-analysis confirmed soy isoflavones had no estrogenic effect in postmenopausal women's endotheliums either (Viscardi et al., 2025).
The studies that DID show negative effects?
They used dosages WAY higher than what people actually eat.
We're talking amounts nobody consumes in real life.
At typical dietary intakes - the amount you'd get from tofu, edamame, or soy milk - soy is just as healthful as other beans.
Now, there ARE some considerations:
Pregnant women and young children might want to avoid making soy a staple protein source.
Their hormonal systems are more delicate and still developing.
But for most adults?
The feminizing concerns simply aren't supported by current meta-analytic evidence.
So if you've been avoiding soy because you thought it would mess with your hormones?
You can relax.
The fear was overblown.
What other nutrition myths have you been told that turned out to be wrong?
