title: Dietary Protein Intake Is Protective Against Loss of Grip Strength Among Older Adults in the Framingham Offspring Cohort.
abstract: BACKGROUND
  Age-related decline in muscle strength is an important public health issue for older adults. Dietary protein has been associated with maintenance of muscle mass, yet its relation to muscle strength remains unclear.
  
  
  METHODS
  We determined the association of dietary protein (total, animal, and plant) intake, measured by food frequency questionnaire, with change in grip strength over 6 years in 1,746 men and women from the Framingham Offspring cohort.
  
  
  RESULTS
  Mean age at baseline was 58.7 years (range: 29-85), and mean total, animal, and plant protein intakes were 79, 57, and 22 g/d, respectively. Adjusted baseline mean grip strength did not differ across quartiles of energy-adjusted total, animal or protein intake. Greater protein intake, regardless of source, was associated with less decrease in grip strength (all p for trend ≤.05): participants in the lowest quartiles lost 0.17% to 0.27% per year while those in the highest quartiles gained 0.52% to 0.60% per year. In analyses stratified by age, participants aged 60 years or older (n = 646) had similar linear trends on loss of grip strength for total and animal (all p for trend <.03) but not plant protein, while the trends in participants younger than 60 years (n = 896) were not statistically significant.
  
  
  CONCLUSIONS
  Higher dietary intakes of total and animal protein were protective against loss of grip strength in community-dwelling adults aged 60 years and older. Increasing intake of protein from these sources may help maintain muscle strength and support prevention of mobility impairment in older adults.
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
authors.forename: Robert R
authors.initials: RR
authors.lastname: McLean
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
authors.forename: Kelsey M
authors.initials: KM
authors.lastname: Mangano
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
authors.forename: Marian T
authors.initials: MT
authors.lastname: Hannan
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Kiel
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts. ShivaniSahni@hsl.harvard.edu.
authors.forename: Shivani
authors.initials: S
authors.lastname: Sahni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D004044:Dietary Proteins
keywords: Community-based; Diet; Epidemiology; Muscle strength; Nutrition