Tea drinking is linked with a reduced risk of dementia in the elderly according to new research. A study on Taiwanese seniors[1] found that those who kept a diet comprising plant-based food and drinks, dairy products, as well as seafood and fish, are found to exhibit better cognitive performance.
In particular, this latest study data found that tea and fish could potentially help protect the brain from dementia. The risk of the disease was found to be cut down by a remarkable 50 percent for those who consumed both tea and fish four times a week, the study suggested, based on the data from the Nutrition and Health Survey in Taiwan (NAHSIT).
Commenting on this latest published research data, Dr Tim Bond from the Tea Advisory Panel (TAP; www.teaadvisorypanel.com) notes; ‘This was a cohort (following a group of people through time and assessing health outcomes based on potential causes and effects) study of 1 ,436 elderly participants who exhibited no dementia-related symptoms when initially assessed in 1999-2000. The study followed up the cohort 11 years later and assessed cognitive function by the internationally recognised Mini-Mental State Examination score (MMSE). When assessed in 2012 19.53 % of the entire participant group were diagnosed with dementia but people who consumed tea and fish every week were less likely to succumb to cognitive illness. Those who consumed both tea and fish less than once a week had a 24% assessment of dementia but those consuming both more than four times a week had reduced the probability of developing dementia to only 12%
‘Globally we are living longer and need to adopt habits that will allow us to live these later years more productively. This new study has similar findings to previous studies building further evidence for the link between tea consumption and a lower risk of dementia. A 2016 cohort study from Japan[2] on 13,645 elderly (>65 years old) participants using an assessment tool benchmarked against the MMSE assessment tool showed green tea consumption was significantly associated with a lower risk of dementia although no link was found to oolong or black tea. In a 2008 Singapore Longitudinal Ageing Study cohort that followed 1,408 Chinese men and women drinking black and oolong tea for 1£2 years.[3] In this study, total tea intake was significantly associated with a lower prevalence of cognitive impairment. Compared with no or rare tea intake, high tea intake (more than 7 cups) was associated with a 63% reduction in cognitive impairment, medium tea intake (4-6 cups) with 55% reduction and low tea intake (1-3 cups) with a 44% reduction. For cognitive decline, corresponding figures were 43% reduction, 22% and 26%.’
Dr Tim Bond adds: ‘With evidence suggesting that tea could reduce the risk of dementia, understanding the mechanism of action and active ingredient(s) within tea creating a potential protective effect is key. In 2013 a US meta-analysis[4] (involving the calculation of a health outcome by summing together the results of the studies included in the analysis) found that all the studies in the analysis that included tea (all types including black and oolong) and most of the studies on coffee or caffeine in their evaluation found an association with lower cognitive decline. This suggested that plant phenolics and caffeine could be responsible. In laboratory studies evidence that both catechins such as EGCG[5],[6] – Epigallocatechin-3-gallate (EGCG) – the major antioxidant and anti-inflammatory compound in green tea found in high concentrations – and theaflavins[7] within black tea, could be the active substances providing some of these health protective answers. More research work is needed in this area, especially validating these findings in humans’.
SEE www.teaadvisorypanel.com
[1] Chuang S Y, Lo Y L, Wang P N, Pan W H, Dietary Patterns and Foods Associated With Cognitive Function in Taiwanese Older Adults: The Cross-sectional and Longitudinal Studies. J Am Med Dir Assoc. 2019 Jan 7. pii: S1525-8610(18)30591-7. doi: 10.1016/j.jamda.2018.10.017
[2] Tomata Y, Sugiyama K, Kaiho Y, Honkura K, Watanabe S, Zhang S, Green Tea Consumption and the Risk of Incident Dementia in Elderly Japanese: The Ohsaki Cohort 2006 Study. Am J Geriatr Psychiatry. 2016 Oct;24(10):881-9
[3] Ng TP, Feng L, Niti M, Kua EH, Yap KB. Tea consumption and cognitive impairment and decline in older Chinese adults. Am J Clin Nutr. 2008; 88:224£31.
[4] Arab L, Khan F, Lam, H, Epidemiologic Evidence of a Relationship between Tea, Coffee, or Caffeine Consumption and Cognitive Decline. Adv. Nutr. 4: 115£122, 2013; doi:10.3945/an.112.002717.
[5] Hyung S J, DeToma A S, Brender J R, Lee S, Vivekanandan S, Kochi A, Choi J S, Ramamoorthy A, Ruotolo B T, Lim M H, Insights into anti-amyloidogenic properties of the green tea extract (-)-epigallocatechin-3-gallate toward metal-associated amyloid-? species. Proc. Natl. Acad. Sci. U S A, 2013 Mar 5;110(10):3743-8
[6] Chebaro Y, Jiang P, Zang T, Mu Y, Nguyen P H, Mousseau N, Derreumaux P, Structures of A?17-42 trimers in isolation and with five small-molecule drugs using a hierarchical computational procedure. J. Phys. Chem. B, 2012 Jul 26;116(29):8412-22
[7] Ano Y, Ohya R, Kita M, Taniguchi Y, Kondo K, Theaflavins Improve Memory Impairment and Depression-Like Behavior by Regulating Microglial Activation. Molecules 2019, 24, 467-480.
