Abstract and Introduction
Abstract
Objectives: To examine the association between consumption of dairy products and risk of frailty in community-dwelling older adults.
Design: Prospective cohort study.
Setting: General population from the older cohort of the Study on Nutrition and Cardiovascular Risk in Spain.
Participants: Community-dwelling adults aged 60 and older free of frailty at baseline (N = 1,871).
Measurements: From 2008 to 2010, food consumption was assessed using a validated diet history. Participants were examined again in 2012 to assess incident frailty, defined as at least three of the five Fried criteria (exhaustion, weakness, low physical activity, slow walking speed, unintentional weight loss). Adjusted odds ratios (OR) for the main confounders were obtained using logistic regression.
Results: During follow-up, 134 new cases of frailty were identified. Participants consuming seven or more servings per week of low-fat milk and yogurt had lower incidence of frailty (OR = 0.52; 95% confidence interval (CI) = 0.29–0.90; P for trend = .03) than those consuming less than one serving per week. Specifically, consumers of seven or more servings per week of low-fat milk and yogurt had less risk of slow walking speed (OR = 0.64, 95% CI = 0.44–0.92, P trend = .01) and of weight loss (OR = 0.54, 95% CI = 0.33–0.87, P trend = .02). Consuming seven or more servings per week of whole milk or yogurt (OR = 1.53, 95% CI = 0.90–2.60, P trend = .10) or of cheese (OR = 0.91, 95% CI = 0.52–1.61; P trend = .61) was not associated with incident frailty.
Conclusion: Higher consumption of low-fat milk and yogurt was associated with lower risk of frailty and, specifically, of slow walking speed and weight loss. Current recommendations to prevent frailty include protein supplementation; thus, although experimental research is needed, increasing the consumption of low-fat yogurt and milk might prevent frailty in older adults.
Introduction
Frailty is a common geriatric syndrome that results from cumulative decline in many physiological systems during a lifetime and is characterized by an alteration in homeostasis that confers a state of vulnerability after even small stressor events.[1] Frailty is of clinical and public health relevance because it increases the risk of falls, disability, and death.[2,3]
There is emerging evidence that links diet to frailty. Age-related anorexia and low-calorie diets might presage frailty.[4] Adherence to an index of diet quality[5] or to a Mediterranean diet has been related to lower risk of frailty,[6,7] but there is little evidence of the effect of consumption of particular foods or selected nutrients on the risk of frailty. This information is needed to identify the specific components of diet that may explain its effects on frailty and to help develop food recommendations to prevent frailty and its adverse consequences. Specifically, high intake of antioxidant vitamins and proteins might diminish the risk of frailty.[8] Moreover, it is biologically plausible that bioavailable calcium and phosphorus could delay sarcopenia and osteoporosis, which are closely related to some frailty criteria.[9]
Dairy products are substantial sources of proteins, vitamins, and minerals, especially for elderly adults.[10,11] Thus, dairy products could theoretically reduce the incidence of frailty, but high milk consumption could also have deleterious effects. It has been postulated that exposure to high levels of D-galactose, a product of lactose hydrolysis, increases oxidative stress and therefore may promote aging. High milk intake was associated with high mortality and fracture incidence in a large cohort study.[12] Whole dairy products also add saturated fatty acids to the diet. Despite this lack of consensus, the main dietary guidelines in Spain and other countries recommend daily consumption of dairy products as part of a healthy diet for the general population.[13,14] Some studies have found positive effects of dairy consumption in elderly people, but the evidence base for this recommendation remains scarce. One study found that daily consumption of milk and milk products was inversely associated with functional disability in older men.[15] Another found that women who consumed dairy products had greater whole-body lean mass and better physical performance than those who did not.[16] Both studies had a cross-sectional design and did not assess frailty.
Therefore, this study aimed to examine the prospective association between habitual consumption of dairy products and the risk of frailty in older adults living in the community.
J Am Geriatr Soc. 2015;63(9):1852-1860. © 2015 Blackwell Publishing
