If I eat mindlessly while watching television, reading, or talking with someone else, I can go through an entire meal without tasting the food, without even noticing that I've been eating. The plate is empty but I didn't enjoy the food - I had all of the calories and little of the pleasure.
When we understand the connection between how we live and how long we live, it's easier to make different choices. Instead of viewing the time we spend with friends and family as luxuries, we can see that these relationships are among the most powerful determinants of our well-being and survival.
When we realize that something as primal as the food that we choose to eat each day makes such an important difference in addressing both global warming and personal health, it empowers us and imbues these choices with meaning. If it's meaningful, then it's sustainable - and a meaningful life is a longer life.
Not everything that lowers HDL is bad for you. If you change from a high-fat, high-cholesterol diet to a healthy low-fat, low-cholesterol diet, your HDL levels may stay the same or even decrease because there is less need for it. When you have less garbage, you need fewer garbage trucks to remove it, so your body may make less HDL.