{"url":"https://whatshealthyandwhy.com/tea/black-tea","path":"/tea/black-tea","alternates":{"json":"https://whatshealthyandwhy.com/api/articles/tea/black-tea.json","markdown":"https://whatshealthyandwhy.com/tea/black-tea.md"},"topic":{"slug":"tea","name":"Tea","url":"https://whatshealthyandwhy.com/tea"},"slug":"black-tea","order":6,"title":"Black Tea","question":"Does black tea lower blood pressure and cholesterol?","answer":"Black tea probably lowers blood pressure and LDL cholesterol slightly (about 1–2 mmHg and 7.5 mg/dL), per meta-analyses of randomized trials.","description":"How black tea's unique theaflavins and thearubigins support cardiovascular health, blood pressure, and gut function","confidence":4,"confidenceNote":"Two meta-analyses of RCTs agree (blood pressure: 11 trials, 378 people), but effects are small and cholesterol results used about 5 cups daily.","evidenceSummary":{"metaAnalysisCount":2,"totalParticipants":"378+","replicated":true,"newestStudyYear":2019},"category":{"categoryTitle":"What's Good For You","categorySlug":"good-for-you","subcategoryName":"Foods & Drinks","subcategorySlug":"foods","url":"https://whatshealthyandwhy.com/explore/good-for-you/foods"},"actions":["For blood pressure and cholesterol, drink black tea daily; the cholesterol trials averaged about 5 cups for 3–4 weeks [1][2].","Count its caffeine: 40–70 mg per cup, more than green tea and about half of coffee."],"cautions":["Caffeine is 40–70 mg per cup, so five cups a day adds 200–350 mg; cut back if you are sensitive to caffeine.","Effects are small (about 1–2 mmHg); black tea is not a substitute for blood pressure or cholesterol treatment [2].","Gut-microbiome benefits come from lab and mouse studies, not human trials [3]."],"simpleText":"Black tea is the most widely consumed tea in the world and the most oxidized of the true teas. During processing, its catechins are converted into theaflavins and thearubigins -- compounds unique to black tea that give it its dark color and bold flavor. Research links regular black tea consumption to improved cardiovascular health, modest blood pressure reductions, and a healthier gut microbiome [1][2].\n\nA typical cup of black tea contains 40-70 mg of caffeine -- more than green tea but roughly half what you would get from coffee. For the catechin-focused benefits, see our Green Tea page -- black tea's oxidation converts catechins into different but still beneficial compounds.","mediumText":"What makes black tea different\n\nBlack tea undergoes full oxidation during processing, a step that fundamentally changes its polyphenol chemistry. While green tea preserves catechins like EGCG, black tea's enzymatic oxidation converts most catechins into two classes of compounds: theaflavins (about 1-2% of dry weight) and thearubigins (about 10-20% of dry weight) [4]. These larger, more complex polyphenols have distinct biological activities.\n\nTheaflavins have demonstrated antioxidant potency comparable to catechins in vitro. They inhibit LDL oxidation, reduce cholesterol absorption in the intestine, and improve endothelial function [1]. A meta-analysis of randomized controlled trials found that black tea consumption reduced LDL cholesterol by approximately 7.5 mg/dL over several weeks of regular intake [1].\n\nThe blood pressure benefits appear consistent across studies. Greyling et al. (2014) conducted a meta-analysis of 11 RCTs and found that black tea reduced systolic blood pressure by approximately 1.8 mmHg and diastolic blood pressure by 1.3 mmHg [2]. While modest, these reductions at a population level translate into meaningful decreases in cardiovascular event risk.\n\nBlack tea also acts as a prebiotic. Its polyphenols that are not absorbed in the small intestine travel to the colon, where gut bacteria metabolize them into smaller bioactive compounds. This process promotes the growth of beneficial bacteria like Lactobacillus and Bifidobacterium [3].","deepText":"Evidence review and mechanisms\n\nThe cardiovascular benefits of black tea have been examined in multiple meta-analyses. Davies et al. (2003) analyzed pooled data from controlled trials and concluded that regular consumption of approximately 5 cups per day over 3-4 weeks produces statistically significant reductions in total and LDL cholesterol [1]. The effect appears mediated by theaflavins interfering with micellar solubility of cholesterol in the gut, reducing intestinal absorption.\n\nGreyling et al. (2014) performed the most comprehensive meta-analysis on black tea and blood pressure to date, including 11 RCTs with a combined 378 subjects. The pooled analysis showed significant reductions in both systolic (-1.8 mmHg, 95% CI: -3.0 to -0.6) and diastolic (-1.3 mmHg, 95% CI: -2.0 to -0.6) blood pressure [2]. The mechanism is thought to involve improved nitric oxide bioavailability and endothelial function through theaflavin-mediated suppression of endothelin-1.\n\nHenning et al. (2018) demonstrated in both in vitro and mouse models that black tea polyphenols shift the gut microbiota composition in ways associated with improved metabolic health. Specifically, black tea increased the Bacteroidetes-to-Firmicutes ratio and promoted short-chain fatty acid production, changes associated with reduced body weight and improved insulin sensitivity [3]. These prebiotic effects are distinct from green tea, whose smaller catechins are mostly absorbed before reaching the colon.\n\nThe caffeine content of black tea (40-70 mg per cup) provides a moderate stimulant effect. Combined with L-theanine (approximately 25 mg per cup), black tea produces a calmer alertness compared to coffee, with less jitteriness reported in subjective studies [4].","deepTruncated":false,"references":[{"id":"1","title":"Black tea consumption reduces total and LDL cholesterol in mildly hypercholesterolemic adults","authors":"Davies MJ, Judd JT, Baer DJ, Clevidence BA, Paul DR, Edwards AJ, Wiseman SA, Muesing RA, Chen SC","year":2003,"journal":"Journal of Nutrition","pmid":"14519829","url":"https://pubmed.ncbi.nlm.nih.gov/14519829/"},{"id":"2","title":"The effect of black tea on blood pressure: a systematic review with meta-analysis of randomized controlled trials","authors":"Greyling A, Ras RT, Zock PL, Lorenz M, Hopman MT, Thijssen DH, Draijer R","year":2014,"journal":"PLoS One","pmid":"25079225","url":"https://pubmed.ncbi.nlm.nih.gov/25079225/"},{"id":"3","title":"Decaffeinated green and black tea polyphenols decrease weight gain and alter microbiome populations and function in diet-induced obese mice","authors":"Henning SM, Yang J, Hsu M, Lee RP, Grojean EM, Ly A, Tseng CH, Heber D, Li Z","year":2018,"journal":"European Journal of Nutrition","pmid":"28965248","url":"https://pubmed.ncbi.nlm.nih.gov/28965248/"},{"id":"4","title":"Chemistry and biological activities of processed Camellia sinensis teas: a comprehensive review","authors":"Zhang L, Ho CT, Zhou J, Santos JS, Armstrong L, Granato D","year":2019,"journal":"Comprehensive Reviews in Food Science and Food Safety","pmid":"33336903","url":"https://pubmed.ncbi.nlm.nih.gov/33336903/"}],"wordCount":566,"source":{"path":"src/content/topics/tea/black-tea.md"},"citeAs":"“Does black tea lower blood pressure and cholesterol?.” What's Healthy and Why. https://whatshealthyandwhy.com/tea/black-tea","notice":"General information backed by peer-reviewed research, not medical advice."}