Dr. Gersen believed that if people received the proper nutrition they would not get sick.
I don't know Dr. Gersen but I believe he is wrong and you can tell him that I said so.
(If he is bigger than me, don't give him my real name)
We (or most of us) are warm blooded creatures and have a totally different immune system than fish. Fish slime carries immunity from many disease invaders including paracites, most of us humans do not exude slime, although I once dated a girl in Colorado who resembled a flounder, she wasn't slimy though. But a real good swimmer.
Anyway, our immune system works mainly through our blood where as a fish immune system works in it's entire body and outside it in their slime.
Fish are exposed to more toxins than we are due to the fact that they are in water and every mineral on earth is in our oceans. What ever is in the air, is also in the water so fish evolved to be resistant to these malady's.
Whenever I go to Mexico, I get sick, And I never get sick. Mexican people don't get sick. In Viet Nam I had to take an anti malaria pill every day, the Vietnamese people didn't normally get malaria. That is because they are exposed to it from birth and we Americans are only exposed to things like Mrs Pauls Fish Sticks and Hamburger Helper. We are inoculated for everything else. Plus our diet will not protect us from infection no matter what Dr. Gersen thinks.

For some reason that I don't know (and I don't know a lot of things) fish in breeding condition do not get sick. In Dr. Gersens defense there is some evidence that pregnant women are more immune from some diseases and some seem to get better from things like MS for instance. The immunity lapses when she gives birth. No one knows why.
But as I said, fish are different and a good diet that gets the fish into breeding condition will help the fish become immune from everything
(except being put into one of those Mrs Pauls fish sticks)
Speaking of fish sticks, I just came back from a county funded Veterans BarBeCue. There were thousands of Vets there and it was free. I was very proud to be there among so many Hero's who fought and protected this country, from WW2 to Korea to Viet Nam to the Middle East. They were all there and some of the WW2 guys were barely able to move around. They had carts to help them from their car to the event as the place is huge.
I met one on my Nam buddies there and we shared some war stories.
It was typical military though and they must had some military people organize it. They had about 7 tables where you could get hamburgers or hot dogs, then about 100 yards away there was one lone table that had the ketchup, mustard and sour kraut. Then 100 yards in the other direction there was one table and one guy serving beer to the 3 or 4,000 people there.

Then there was a table from "Panera" a large bread and pastry company.
There was a huge line for that and I walked to the front of the line to see what they had. The event just opened maybe 20 minutes before and they ran out of food. Someone went someplace for more. An hour later when I left, they were still waiting for that stuff to come back.
But it was free and a great event so I can't complain. I can use some days without dessert anyway. :beer: