The association between total energy intake and early mortality:: data from the Malmo Diet and Cancer Study

Objectives. In animal studies, low energy intake (EI) has been associated with a longer lifespan. We examine whether El is an independent risk factor for prospective all-cause mortality, cardiovascular and cancer mortality in humans. Design. Population-based, prospective cohort study. Setting and subjects. The Malmo Diet and Cancer Study is a population-based prospective cohort study. A total of 28 098 individuals, mean age 58.2 years, completed questionnaires on diet and life-style and attended a physical examination during 1991-96. Main outcome measures. Information on mortality was acquired from national registries during a mean follow-up time of 6.6 years. Subjects were categorized by quartiles of total El. The first quartile was used as a reference point in estimating multivariate relative risks (RR; 95% Cl, Cox's regression model). Adjustments were made for confounding by age and various life-style factors. Results. The lowest total mortality was observed for women in the third quartile (RR: 0.74; CI: 0.57-0.96) and for men in the second and third quartiles (RR: 0.85; Cl: 0.69-1.04 and RR: 0.85; Cl: 0.69-1.04 respectively). Similar U-shaped patterns were observed for cardiovascular mortality amongst women and cancer mortality amongst men. A statistically significant trend (P = 0.029) towards lower cardiovascular mortality from the first to the fourth quartile was observed for men. Conclusions. Low caloric consumers did, on average, not have lower mortality than average or high caloric consumers. Generally, individuals approximately meeting national recommendations for total El had the lowest mortality. For men, high caloric intake was associated with lower cardiovascular mortality.