We cannot be healthy if the food we eat is not healthy. Whether you eat meat or are a vegan, the quality of the food you consume is directly related to how healthy you are. There are other factors, exercise, for one, plays a major role in health care. Getting up off the couch and going outside, even just for a walk, matters.
The issue becomes more complicated when we look at the health of the environment. If the air we breathe is polluted, the water we drink despoiled, the soil our food is grown in contaminated, then it matters little how many green, orange and purple foods you eat. Vegan or carnivore, a polluted foodscape infects the food choices you make.
Soil health, air and water quality are major environmental issues, but they are also major health care issues. We need an healthcare system that understands this relationship.