Groenten en fruit voor beter uithoudingsvermogen bij het ouder worden*
Uit een studie onder 687 vijfenzestigplussers blijkt dat het regelmatig eten van verschillende groenten en fruit zorg voor een beter uithoudingsvermogen. Drie jaar lang werden de deelnemers gevolgd en werden bloedwaarden
carotenoïden vastgelegd. Groenten en fruit, rijk aan kleuren, bevatten veel carotenoïden waardoor bloedwaarden hiervan een goede indicatie zijn voor de gegeten hoeveelheid groenten en fruit. Deelnemers met de hoogste bloedwaarden carotenoïden hadden duidelijk een beter uithoudingsvermogen waardor ze langer en steviger konden wandelen. Deze studie is een bevestiging van eerdere studies waarbij voldoende carotenoïden al in verband gebracht werden met meer spierkracht en beter fysiek functioneren van ouderen.
Carotenoid Nutrients Proven to Keep Senior Citizens Active
Senior citizens who consume a high dietary intake of carotenoids, nutrients found in colored fruits and vegetables such as carrots, peppers, mangoes and kiwi fruit, are able to walk 'longer and stronger' than those with a low dietary intake, suggest the results of a new study published by the Journal of Nutrition, Health and Ageing.
Researchers at Johns Hopkins Medical Center used blood tests to measure levels of carotenoids in 687 older adults aged sixty-five and over, and subsequently assessed the results against the physical walking performance of the trial participants.
Results showed that a higher dietary intake of fruits and vegetables, as indicated by a higher blood carotenoid level, was associated with a significant protective effect against physical degeneration over the course of three years, as measured by a strong or weak walking performance. [1]
The latest findings are the second such study to examine the connection between these dietary factors and sustainable physical performance in aging. Previous research, also carried out by Johns Hopkins and forming part of the larger Women's Health and Aging Study, revealed that "low serum carotenoid levels, an indicator of low intake of fruits and vegetables, are independent predictors of the progression towards severe walking disability among older women living in the community." [2]
Prior to both studies, the link between a low carotenoid intake and poor muscle strength had been established [3], as had a more general correlation between fruit and vegetable consumption and functional disability in senior citizens. [4]
Researchers in the current study felt that their results may be particularly important given that such mobility assessments can be accurate predictors of future disability and even mortality, and that the findings could help senior citizens in maintaining independence and quality of life with aging.
Lead author Dr Alipanah and colleagues suggested a number of explanations for the findings, including that the antioxidant properties of the nutrients could protect against the progression of aging and may help to dampen down a type of inflammation unique to muscle weakness and physical decline. The research team also suggested that physical degeneration may on occasion simply be related to undernutrition and that an increased intake of fruits and vegetables could be indicative of consuming enough calories to lend to a strong physical walking performance.
According to the US Department of Agriculture, the highest levels of carotenoids are found in collards, sweetcorn, tomatoes, watermelon, pink grapefruit, pumpkin, butternut squash and carrots. Guidelines recommend an intake of around 6mg each day, or equivalent to eating three portions of carotenoid rich foods. [5]
[1] Alipanah et al. Low Serum Carotenoids Are Associated With A Decline In Walking Speed In Older Women. The Journal of Nutrition, Health & Aging. 2009, 13; 3: 170-175.
[2] Semba et al. Low serum carotenoids and development of severe walking disability among older women living in the community: the Women's Health and Aging Study I. Age Ageing. 2007 January. 36; 1:62-67.
[3] Cesari M, Pahor M, Bartali B, et al. Antioxidants and physical performance in elderly persons: the Invecchiare in Chianti (InCHIANTI) study. Am J Clin Nutr. 2004. 79:289-94.
[4] Houston DK, Stevens J, Cai J, Haines PS. Dairy, fruit and vegetables intakes and functional limitations and disability in a biracial cohort: the Atherosclerosis Risk in Communities Study. Am J Clin Nutr. 2005. 81:515-22.
[5] Holden et al. Carotenoid Content of U.S. Foods: An Update of the Database. Journal Of Food Composition And Analysis. 1999. 12; 169-196.
(Augustus
2009)