Despite its reputation for being a rich source of protein, you would likely have to swallow gallons of semen to see any dietary health benefits.
Whether or not it's “okay” to swallow semen depends on whether or not you're okay with it. There's nothing unhealthy, wrong, or dirty about.
Some of the studies into the effects of swallowing semen are described here. yeovilcatsprotection.info
Semen is neither harmful or beneficial to your health when swallowed.