title: Caloric restriction may reverse age-related autonomic decline in humans.
abstract: Caloric restriction (CR) retards aging in laboratory rodents. No information is available on the effects of long-term CR on physiologic markers of aging and longevity in humans. Heart rate variability (HRV) is a marker for cardiac autonomic functioning. The progressive decline in HRV with aging and the association of higher HRV with better health outcomes are well established. Heart rate variability assessment is a reliable tool by which the effects of CR on autonomic function can be assessed. Time- and frequency-domain analyses compared 24-h HRV in 22 CR individuals aged 35-82 years and 20 age-matched controls eating Western diets (WD). The CR group was significantly leaner than the WD group. Heart rate was significantly lower, and virtually, all HRV values were significantly higher in the CR group than in the WD group (P < 0.002). Heart rate variability in the CR individuals was comparable with published norms for healthy individuals 20 years younger. In addition, when differences in heart rate (HR) and HRV between CR and WD were compared with previously published changes in HRV induced in healthy adults given atenolol, percent differences in each measure were generally similar in direction and magnitude and suggested declines in sympathetic and increases in parasympathetic modulation of HR and increased circadian variability associated with CR. These findings provide evidence that CR has direct systemic effects that counter the expected age-associated changes in autonomic function so that HRV indexes in CR individuals are similar to those of individuals 20 years younger eating WDs.
authors.affiliation: HRV Laboratory, Washington University School of Medicine, St. Louis, MO 63110, USA. pstein@dom.wustl.edu
authors.forename: Phyllis K
authors.initials: PK
authors.lastname: Stein
authors.forename: Andreea
authors.initials: A
authors.lastname: Soare
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Meyer
authors.forename: Roberto
authors.initials: R
authors.lastname: Cangemi
authors.forename: John O
authors.initials: JO
authors.lastname: Holloszy
authors.forename: Luigi
authors.initials: L
authors.lastname: Fontana
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001341:Autonomic Nervous System / Q000502:physiology*; D031204:Caloric Restriction; D016022:Case-Control Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008136:Longevity / Q000502:physiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors