Can a Mediterranean diet late in life undo all the damage that eating junk food did earlier?

If you learn the error of your ways when you're in your 50s and switch to fruit, fresh vegetables, whole grains and omega 3 fish, will your body come right or are you permanently knackered after a lifetime of fizzy drinks, pies chips and lollies?Can a Mediterranean diet late in life undo all the damage that eating junk food did earlier?
You can lose weight, but your heart and other internal body parts will never be as strong as they could be. They can be strong, but it would be very hard to make a full turn and change your heart into that of an Olympic athlete. But, don't be discouraged. Just keep up a good diet and exercise plan and you'll be healthy.



EDIT: Yes, it will come down once you start making changes and get your cholesterol level down, as well as blood pressure.