Here's a topic on the most important aspects of QoL. Nutrition is an obvious example, and because of how rare some essentials are amongst diets -- omega 3 was evidenced benefiting telomere lengths, which is "huge"; and humans are somehow still proficient, so the hints at further efficacy are immense. Social interest and investment, personality, attractiveness, skillfulness, anatomy, energy levels, and other aspects of genetic expression are basing on nutriments, a most simple, logical method of cellular energy / youth. ..Others are categorizations of home and business chemistry, technology, etc..