what health benefit does the human body get from sea water... or 
health benefits if a man spends 1 hour a day in the caribbean sea
waters?

http://www.health-spa.org/ states that Seawater baths heated to 105
deg F helps relax and soothe sore muscles.
It goes on to say that anecdotal reports of the benefits of seawater
exist from people with dermatitis or psoriasis (these are skin
diseases).  One of the treatments for Dermatitis is a chemical mixture
known as Salicylic acid, which is commonly available as a cream or
lotion.  The salt in the sea might partially replicate the effect this
drug has.  Sorry this is slightly off the topic, but then again, it's
free.

Well. you get to relax... that's gotta be a health benefit. :)

Hi,
I could not find a comprehensive answer to your question, however the
following article discusses 'The Magic of Sea Water and Seaweed
for Health and Well-being':
'The minerals in the sea and its products have been established to
have a wonderful healing effect on the body and mind. Hippocrates,
famous Greek physician had mentioned about the treatment and healing
through sea water.'

http://www.travel-watch.com/seaweed.htm 

Regards, 
Ali

legend1,
I can attest from personal experience that sea water can be very good
for allergies, runny nose problems etc. I am a diver and sometimes
have bad allergies, whenever I go diving they disappear almost
entirely. I have heard it said that it's the effect of the salt water
clearing the nasal pathways, so I suppose you could do this at home if
you wanted!

Other than that, spending time in the Caribbean can be pretty good for
your mental health!

Cheers,
dannidin