“This study is among the first to evaluate longitudinal associations between plasma lutein and zeaxanthin concentrations and incident frailty and changes in musculoskeletal outcomes in older adults.” write the Dublin-based researchers.
The research team extracted data from the first five waves (2010 to 2018) of The Irish Longitudinal Study of Aging (TILDA), a nationally representative, longitudinal study of aging that included baseline data from 8,500 participants aged over 50 years in Ireland.
Lutein, zeaxanthin and aging
Found in sources such as dark leafy greens, peas, summer squash, broccoli, carrots, parsley, paprika, sweet corn, and eggs, lutein and zeaxanthin are primarily associated with improving eye health and mitigating age-related macular degeneration.
However, emerging evidence suggests that these two compounds may also play a protective role in other conditions caused by inflammatory and oxidative stress, including frailty, sarcopenia, and osteoporosis.
“Healthier dietary patterns that are rich in fruits and vegetables are associated with better maintenance of musculoskeletal health and lower incidence of frailty in older adults in observational studies.”the researchers state.
“Since aging is associated with a decline in the endogenous antioxidant defense system, increased dietary intake of exogenous antioxidants such as carotenoids may help correct redox balance and reduce oxidative damage.”
Cross-sectional analyzes of a cohort of 4,513 TILDA Wave 1 participants compared plasma lutein and zeaxanthin concentrations with grip strength, usual gait speed, timed get-up-and-go (TUG), probable sarcopenia, and bone mass at baseline. Meanwhile, longitudinal analyzes (n = 1425–3100) assessed changes over time in habitual gait speed and bone stiffness index (Wave 3, 2014-2015), grip strength and probable sarcopenia (Wave 4, 2016), and TAMPER and incident weakness (wave 5, 2018).
Data were analyzed using linear and ordinal logistic regression, adjusted for variables including age, sex, body mass index, education, physical activity, number of chronic diseases, alcohol consumption, smoking, and unintentional weight loss.
“We show that among participants who were not frail at baseline, lower plasma concentrations of lutein and zeaxanthin were longitudinally associated with increased odds of progression to a higher category of frailty (eg, pre-frailty or frailty) after 8 years of tracking,”the researchers concluded.
Specifically, they noted that each 100 nmol/L increase in baseline plasma concentration of lutein and zeaxanthin (roughly equivalent to two additional servings per day of lutein-rich vegetables for four weeks) was associated with 11–20% and 27– 43% lower concentration chances corresponding to moving to a higher weakness category.
In addition, baseline carotenoid concentrations showed positive associations with several indices of musculoskeletal health cross-sectionally, but were not predictive of longitudinal changes in these outcomes over 4 to 8 years. No associations were found between plasma carotenoid concentrations and probable sarcopenia.
“A longer follow-up period than that used in the current study (4-8 years depending on outcome) may be needed to detect an effect of lutein and zeaxanthin status on changes in physical performance over time “the study noted. “As such, it will be interesting to explore these relationships further in future Waves of TILDA.”
source: Experimental gerontology
“Plasma lutein and zeaxanthin concentrations associated with musculoskeletal health and incident frailty in the Irish Longitudinal Study of Aging (TILDA)”.
Authors: Colin H. Murphy et al.