I just read an article about a 100 year old who credits chocolate for keeping her going. Her daughter says that Edna Hoover, her mother eats some chocolate everyday and up to 2 pounds a week! If you're thinking what I'm going to say next is go ye and do likewise then my answer is no.
I think life is all about balance. And I'm sure Edna eats a balanced diet or did or might not at all and is just lucky to have a strong body. My maternal grandmother died at 92 and enjoyed her chocolates regularly. However, I remember she ate very balanced meals and always had breakfast fit for a queen. She may not always have though.
I am a stickler for balance and I hate regret. I am committed to doing what is right as much as I can especially if it's in my power to do so. Eat some chocolate - preferably some with a decent amount of cocoa and enjoy it but also try to do what's recommended - 5 fruit and veg a day etc. I can't say I'm there yet but I do try.