I picked the food to simplify things, ok any diet high in trans fats,sat fats,crap etc is going to shorten your life especially if you take no exercise.
The fact is if you don't manage to breast feed your child it is NOT the end of the world regarding health,your child is NOT doomed.
If you manage to breast feed great but it does NOT mean you can sit on your ivory tower thinking you have ensured life long good health.
A healthy child needs a lot more than 6 months of breast milk. It needs a decent supply of food,exercise and fresh air. You can still raise perfectly healthy children and have a huge impact on their health regardless of whether they were breast fed or not. If that isn't the case I'm not sure what the point of campaigns like the 5 a day scheme etc are.
I think most scientists are of the opinion that healthy diet and exercise are extremely beneficial to good health regardless of how you were fed as a baby. Not sure how that is absurd