The keys to longevity and vigor into old age, as I understand the research, are in this order. Inherited genes, exercise and diet.
Moose, one way I eat huge quantities of vegetables is by making really rich bone broth from the bones of whatever meats I eat- I pressure cook the bones for hours with a TBS of vinegar to help extract calcium. The broth is the base for stews I make with various beans, whole grains, and a wide range and massive amount of vegetables- most from my own garden (this time of the year, out of the freezer). I also use a bit of smoked meat, and fresh meat, but at much lower ratio than is in the usual American diet. This is my standard lunch out of a thermos during the work week. It was raining today so I made 3 gallons of stew- 1 pint per lunch.
Cooking vegetables in a meat broth turns them into something the most carnivorous among us can appreciate.