Red meat has been shown to have high amounts of fat and cholesterol, which increases the risk for cardiovascular disease, obesity, cancer, Type II diabetes, and other health issues. Meanwhile, a diet high in fruits and vegetables contains essential vitamins, minerals, fibers, and more, reducing the risk for the same diseases that red meat increases the risk for. Vegetarian eating has been shown to reduce the risk of death from ischemic (meaning not getting enough blood or oxygen) heart disease, and contribute to lower cholesterol levels, blood pressure, hypertension, and Type II diabetes rates. Furthermore, vegetarians "tend to have a lower body mass index" than meat-eaters.
Vegetarianism can be just as unhealthy as a normal diet. There are plenty of unhealthy foods, such as chocolate, potatoes, and other foods that are vegetarian. Meat actually contains lots of protein and nutrients that are difficult to get from plants. Being vegetarian does not necessarily make one healthy, and a healthy diet has nothing to do with eating meat or not.
[P1] Vegetarian diets contribute to a lower risk of chronic disease as compared to meat-containing diets.