Isn’t the consumption of sardines related to gout?
Many high protein foods can cause gout, as well as kidney issues. If you are someone who has a history of gout, or kidney problems, I'd certainly limit the amount of protein consumed. Probably talk to your doc about it, and ask how much protein consumption is okay for you.
I've read older folks need more protein. But certainly one doesn't want to go overboard. Same thing goes for any food group. Check with your doc before a making a major change in diet though.
All that said, I believe sardines are one of the highest quality proteins one can eat.