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Cited by 170Tea Polyphenols and EffectsCoffee research and impactsBlood Pressure and Hypertension Studies

Effects on blood pressure of drinking green and black tea

Hodgson, Jonathan M., Puddey, Ian B., Burke, Valerie, Beilin, Lawrence J., Jordan, Nerissa·1999·Journal of Hypertension
DOI 10.1097/00004872-199917040-00002
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Abstract

BACKGROUND: The flavonoid components of tea have been associated in epidemiological studies with a decreased risk of cardiovascular disease. Flavonoids have been shown to have antioxidant and vasodilator effects in vitro; we therefore postulated that drinking green or black tea attenuates the well-characterized acute pressor response to caffeine and lowers blood pressure during regular consumption. OBJECTIVE: To determine whether green and black tea can attenuate the transient pressor effect of caffeine, or lower blood pressure during regular consumption. METHODS: In the first study, the acute effects of four hot drinks - green tea and black tea (at a dose equivalent to four standard cups), water matched to the teas for caffeine content ('caffeine') and water - were assessed in 20 normotensive men using a Latin-Square designed study. Clinic blood pressure was measured before and 30 and 60 min after each drink had been ingested. In the second study, the effects on blood pressure of regular green and black tea ingestion were examined in 13 subjects with high-normal systolic blood pressure and mild systolic hypertension (systolic blood pressure in the range 130-150 mmHg) using a three-period crossover study. Five cups per day of green tea, black tea and caffeine (in hot water and matched to the teas) were consumed for 7 days each, in random order. Twenty-four hour ambulatory blood pressure was measured at the end of each seven-day intervention. Results are presented as means and 95% confidence intervals (CI). RESULTS: An acute pressor response to caffeine was observed. Relative to caffeine, there were further acute increases in systolic and diastolic blood pressure at 30 min among those drinking green tea [5.5 mmHg (95%CI -1.4 to 12.4) and 3.1 mmHg (95%CI -0.1 to 6.3), respectively] and black tea [10.7 mmHg (95%CI 4.0 to 17.4) and 5.1 mmHg (95%CI 1.8 to 8.4), respectively]. The changes in blood pressure at 60 min were not significant The effect on 24-h ambulatory systolic and diastolic blood pressure of regular drinking of green tea [increases of 1.7 mmHg (95%CI -1.6 to 5.0) and 0.9 mmHg (95%CI -1.3 to 3.1), respectively] or black tea [increase of 0.7 mmHg (95%CI -2.6 to 4.0) and decrease of 0.7 mmHg (95%CI -2.9 to 1.5), respectively] was not significant relative to caffeine. CONCLUSIONS: Contrary to our initial hypothesis, tea ingestion caused larger acute increases in blood pressure than caffeine alone. However, any acute effects of tea on blood pressure did not translate into significant alterations in ambulatory blood pressure during regular tea consumption.

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Crossref · 10.1097/00004872-199917040-00002

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  • Acute increases in systolic blood pressure, diastolic blood pressure or both, as well as in pulse pressure and mean arterial blood pressure, have been reported after single caffeine doses ranging from 80 to 250 mg in coffee abstainers, in habitual caffeine consumers after 12-48 hours' withdrawal, and after caffeine habituation (300-600 mg per day for six days).

    “Acute increases in SBP, DBP or both, as well as in pulse pressure and mean arterial blood pressure (MABP), have been reported after single doses of caffeine ranging from 80 to 250 mg in coffee abstainers, in habitual caffeine consumers after 12-48 hours' withdrawal and after caffeine habituation (300-600 mg per day for six days)”

    From Scientific Opinion on the safety of caffeine (2015) · cites this paper as Hodgson et al., 1999

  • Hodgson et al. (1999) found that changes in 24-hour ambulatory BP did not differ significantly among interventions (250 mg caffeine in hot water, black tea or green tea, five cups/day for seven days) with respect to baseline in 13 subjects with high-normal SBP and DBP.

    “Changes in 24-hour ambulatory BP did not differ significantly among interventions with respect to baseline.”

    From Scientific Opinion on the safety of caffeine (2015) · cites this paper as Hodgson et al., 1999

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Authors
Hodgson, J. M., Puddey, I. B., Burke, V., Beilin, L. J., & Jordan, N.
Affiliations
The University of Western Australia (AU)
Corresponding author
Hodgson, Jonathan M.
ORCID
Venue
Journal of Hypertension
Publisher
Ovid Technologies (Wolters Kluwer Health)
Published
1999-04
Volume
17
Issue
4
Pages
457-463
ISSN
0263-6352 (ISSN-L)
DOI
10.1097/00004872-199917040-00002
OpenAlex
W2029732176
Cited by
170
References
26
Citations by year
2026: 1 · 2025: 2 · 2023: 2 · 2022: 4 · 2021: 5 · 2020: 6 · 2019: 7 · 2018: 2 · 2017: 6 · 2016: 7 · 2015: 5 · 2014: 14 · 2013: 10 · 2012: 10
FWCI
3.39
Type
journal article
Language
en
Open access
closed
Locations
  • Journal of Hypertension (publishedVersion)
  • PubMed (publishedVersion)
  • UWA Profiles and Research Repository (UWA) (submittedVersion)
Topics
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Tea Polyphenols and Effects
  • Health Sciences › Medicine › Pharmacology › Coffee research and impacts
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Blood Pressure and Hypertension Studies
Keywords
green tea, black tea, blood pressure, flavonoids, ambulatory blood pressure, hypertension, cardiovascular risk, vasodilation, antioxidant activity, cardiovascular risk factors, cardiovascular risk score
MeSH terms
Adult, Aged, Blood Pressure, Caffeine, Female, Flavonoids, Humans, Male, Middle Aged, Plant Extracts, Tea, Cross-Over Studies

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