Written by Greg Arnold, DC, CSCS. Food questionnaire data from participants over 50 years of age in the Farmingham study suggest that increasing protein intake may help preserve muscle mass.
The decline in muscle mass and strength that occurs with aging increases the risk of falls, fractures, disability, and also loss of independence (1, 2). Those over 50 years of age lose 1-2% of muscle mass per year (3). With the loss in muscle mass comes a 1.5% loss in strength per year between the ages of 50 and 60 and then 3% loss per year after the age of 60 (4). In the United States, all of this adds up to an $18.5 billion cost to our healthcare system in 2000 (5).
Now a new study (6) suggests that increasing protein intake may help preserve strength and muscle mass. The study involved 1166 men and 1509 women aged 51 to 69 who were participating in the Framingham study (7). They provided data on their protein intake by completing a 126-item food frequency questionnaire (8) and their leg lean mass and thigh strength was measured with a isometric dynamometer used in previous research (9, 10).
The researchers found total protein intake in men to average 80 grams per day (highest 25% = 101.1 grams per day, lowest 25% = 64.9 grams per day) and an average of 76 grams per day in women (high 25% = 93.4 g/d, lowest 25% = 57.8 g/d). In men, those with the highest 25% of total protein intake had 2.9% more muscle mass compared to the lowest protein intake (17.6 versus 17.1 kilograms lean muscle, p = 0.005), with higher animal protein intake (p = 0.002) but not plant protein (p =0.70) being significant to lean mass. For thigh strength, those with the highest plant protein intake had 5.5% greater thigh strength compared to those with the lowest plant protein intake (22.9 versus 21.7 kilograms of strength, p = 0.01). Total protein (p = 0.08) and animal protein (p = 0.30) failed to have a significant effect on thigh strength.
In women, those with the highest animal protein intake had 2.6 % more lean mass compared to those with the lowest animal protein intake (11.7 versus 11.4 kilograms, p =0.003) while total protein (p = 0.006) and plant protein (p = 0.36) were not a significant contributor to lean mass. For thigh strength, women with the highest plant protein intake had 4.4% more thigh strength compared to those with the lowest plant protein intake (19.0 versus 18.2, p = 0.01). Total protein (p = 0.1) and animal protein (p = 0.30) did not have significant roles in thigh strength.
Unfortunately, the researchers did not provided data on the highest plant and animal protein intakes versus the lowest intakes, only total protein totals. They went on to conclude that “maintaining adequate protein intake with age may help preserve muscle mass and strength in adult men and women”, that “dietary protein types may differentially affect muscle mass and strength”, and “whether plant protein is a marker of dietary quality or has a direct effect on muscle strength needs to be further clarified.”
Source: Sahni, Shivani, et al. “Higher protein intake is associated with higher lean mass and quadriceps muscle strength in adult men and women.” The Journal of nutrition 145.7 (2015): 1569-1575.
© 2015 American Society for Nutrition.
Posted August 20, 2015.
Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY. You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com
References:
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- Visser M, Kritchevsky SB, Goodpaster BH, Newman AB, Nevitt M, Stamm E, Harris TB. Leg muscle mass and composition in relation to lower extremity performance in men and women aged 70 to 79: the health, aging and body composition study. J Am Geriatr Soc 2002;50: 897–904
- Hughes VA, Frontera WR, Roubenoff R, Evans WJ, Singh MA. Longitudinal changes in body composition in older men and women: role of body weight change and physical activity. Am J Clin Nutr 2002;76:473–81
- von Haehling S, Morley JE, Anker SD. From muscle wasting to sarcopenia and myopenia: update 2012. J Cachexia Sarcopenia Muscle 2012;3:213–7
- Janssen I, Shepard DS, Katzmarzyk PT, Roubenoff R. The healthcare costs of sarcopenia in the United States. J Am Geriatr Soc 2004;52: 80–5.
- Higher Protein Intake Is Associated with Higher Lean Mass and Quadriceps Muscle Strength in Adult Men and Women. J Nutr 2015 Jul;145(7):1569-75. doi: 10.3945/jn.114.204925. Epub 2015 May 27
- Kannel WB, Feinleib M, McNamara PM, Garrison RJ, Castelli WP. An investigation of coronary heart disease in families. The Framingham offspring study. Am J Epidemiol 1979;110:281–90
- Rimm EB, Giovannucci EL, Stampfer MJ, Colditz GA, Litin LB, Willett WC. Reproducibility and validity of an expanded self-administered semiquantitative food frequency questionnaire among male health professionals. Am J Epidemiol 1992;135:1114–26, discussion 27–36
- Piao C, Yoshimoto N, Shitama H, Makino K, Wada F, Hachisuka K. Validity and reliability of the measurement of the quardriceps femoris muscle strength with a hand-held dynamometer on the affected side in hemiplegic patients. J UOEH 2004;26:1–11.
- Piva SR, Fitzgerald K, Irrgang JJ, Jones S, Hando BR, Browder DA, Childs JD. Reliability of measures of impairments associated with patellofemoral pain syndrome. BMC Musculoskelet Disord 2006;7:33
