Although the solvents used to decaffeinate coffee are considered safe for humans it's said that decaffeinated coffee is worse for your health than regular coffee that contains caffeine.
Now that's just opinions and so far I've never read anything from medical professionals that can prove that decaffeinated coffee is actually harmful to your health so it's just opinion.
But it's said that coffee that contains caffeine is much better for your heart health than decaffeinated coffee is and coffee without caffeine to me tastes bad.