Green tea and black tea both have meaningful evidence for improving blood circulation, primarily by helping blood vessels relax and widen. Several herbal teas, including hibiscus, ginger, and ginkgo biloba, also show circulatory benefits through different mechanisms. The effects vary depending on the type of tea, how you prepare it, and even whether you add milk.
Green Tea and Blood Vessel Relaxation
Green tea’s circulatory benefits center on its ability to boost nitric oxide production in blood vessel walls. Nitric oxide is a signaling molecule that tells the smooth muscle around arteries to relax, widening the vessel and allowing blood to flow more freely. The key compound involved is EGCG (epigallocatechin gallate), which triggers nitric oxide release through a specific enzyme pathway in the endothelium, the thin layer of cells lining your blood vessels.1PubMed. EGCG, a green tea polyphenol, improves endothelial function and insulin sensitivity, reduces blood pressure, and protects against myocardial I/R injury in SHR
This isn’t just a lab finding. In a study of healthy people, drinking green tea improved flow-mediated dilation (a standard measure of how well arteries expand in response to increased blood flow) by about 3.7% within 30 minutes. Caffeine alone, given at the same dose found in the tea, didn’t produce a significant change, suggesting the benefit comes from the tea’s other compounds rather than the caffeine itself.2PubMed. The acute effect of green tea consumption on endothelial function in healthy individuals
There’s an interesting wrinkle here. When researchers tested pure EGCG supplements head-to-head against actual brewed green tea, only the tea improved vascular function. The supplement, despite containing the same amount of EGCG, didn’t move the needle. This suggests the circulatory benefits of green tea come from the interplay of its many compounds working together, not from any single ingredient you could isolate into a capsule. If you’re drinking green tea for your blood vessels, the cup matters more than the pill.
Black Tea Has Its Own Circulatory Perks
Black tea undergoes more oxidation during processing than green tea, which transforms its catechins into larger compounds called theaflavins. These work through slightly different pathways but still end up improving circulation. In a controlled trial, a dose of 300 mg of theaflavins produced a modest but measurable improvement in microvascular dilation.3PubMed Central. Effect of Tea Theaflavins and Catechins on Microvascular Function
Beyond the direct vessel-relaxing effect, black tea polyphenols and their metabolites — especially those transformed by gut bacteria — appear to work on several fronts relevant to circulation. They can increase nitric oxide availability, reduce inflammation in vessel walls, inhibit the enzyme involved in high blood pressure (the same angiotensin-converting enzyme that ACE-inhibitor drugs target), and reduce platelet clumping.4The American Journal of Clinical Nutrition. Interactions of black tea polyphenols with human gut microbiota: implications for gut and cardiovascular health
The platelet angle is worth a closer look. Lab studies have found that theaflavin and related compounds from black tea inhibit clumping triggered by platelet-activating factor, a molecule the body produces during inflammation.5PubMed. Tea polyphenols inhibit acetyl-CoA:1-alkyl-sn-glycero-3-phosphocholine acetyltransferase (a key enzyme in platelet-activating factor biosynthesis) and platelet-activating factor-induced platelet aggregation This doesn’t mean black tea is a blood thinner in the way aspirin is, but it does suggest a mild anti-clotting influence that could contribute to smoother blood flow over time.
Herbal Teas That Show Promise
If you’re looking beyond green and black tea, several herbal options have evidence for circulatory effects, though the research tends to be thinner and more preliminary.
- Hibiscus: Hibiscus tea, made from the deep-red calyces of the Hibiscus sabdariffa plant, has been studied primarily for blood pressure. Its anthocyanins appear to act as competitive inhibitors of the angiotensin-converting enzyme, the same target that ACE-inhibitor medications go after.6PubMed Central. A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers By blocking production of angiotensin II, a potent vessel-constricting molecule, hibiscus tea may help blood vessels stay more relaxed.
- Ginger: Ginger tea won’t show up on the same vascular function tests that green and black tea ace, but it does something those teas don’t: it raises peripheral skin temperature, a sign that more blood is reaching your extremities. Women who drank a ginger-extract beverage maintained higher palm temperatures than those given a placebo, and the warming effect held regardless of whether the drink itself was hot or cold.7PubMed Central. Hyperthermic Effect of Ginger (Zingiber officinale) Extract-Containing Beverage on Peripheral Skin Surface Temperature in Women The active component is thought to be 6-shogaol, which boosts your body’s heat production.
- Ginkgo biloba: Ginkgo extract, often consumed as a tea or supplement, has shown the ability to increase blood flow velocity in specific vascular beds. In one trial, ginkgo extract boosted blood flow velocity in the ophthalmic artery (which supplies the eye) by about 23%, compared to no change with a placebo.8PubMed. Ginkgo biloba extract increases ocular blood flow velocity A separate study on the tiny blood vessels around the optic nerve found that ginkgo increased blood flow, volume, and velocity at most measurement points.9PubMed Central. Short-term effects of Ginkgo biloba extract on peripapillary retinal blood flow in normal tension glaucoma These findings are narrow — mostly studied in the context of eye health — but they demonstrate a real circulatory effect.
- Hawthorn: Hawthorn berry tea has a long folk-medicine history for heart complaints. Lab research on isolated blood vessels found that hawthorn extract produced an early burst of vasodilation within the first two minutes, which the researchers attributed to increased nitric oxide generation triggering prostacyclin production, another molecule that widens blood vessels.10Journal of Evidence-Based Complementary & Alternative Medicine. The Effect of Hawthorn Extract on Coronary Flow
- Cinnamon: Cinnamon bark tea delivers cinnamaldehyde and cinnamic acid, phenolic compounds with antioxidant and anti-inflammatory properties linked to reduced cardiovascular risk, particularly in people dealing with diabetes, obesity, or high cholesterol.11PubMed Central. Cinnamon: a nutraceutical supplement for the cardiovascular system
- Rooibos: South African rooibos tea contains aspalathin, a compound that reversed inflammatory damage in vascular endothelial cells exposed to inflammatory signals in lab studies, restoring barrier function and reducing inflammatory markers.12Journal of Agriculture and Food Research. Aspalathin-rich unfermented Aspalathus linearsis extract mitigates vascular endothelial inflammation by inhibiting the TNF-α/Hexokinase 2/NF-κB signaling pathway This is cell-culture work, not clinical trial data, so the leap to “drink rooibos for better circulation” is a long one. Still, the mechanism is promising.
Why Adding Milk Changes Everything
If you take milk in your tea, the circulatory benefits may vanish. A randomized crossover trial found that plain black tea increased flow-mediated dilation compared to hot water, but adding milk didn’t just cancel the benefit — it actually pushed vascular function below the control level.13PubMed. Effect of adding milk to black tea on vascular function in healthy men and women: a randomised controlled crossover trial
The culprit appears to be casein, the main protein in cow’s milk. When casein binds to tea polyphenols, it forms complexes that prevent those compounds from interacting with the blood vessel lining. In lab experiments using isolated rat aortic rings, tea induced vessel relaxation and activated the enzyme that produces nitric oxide, but adding milk completely blocked both effects.14PubMed. Addition of milk prevents vascular protective effects of tea
This finding matters for anyone drinking tea specifically for circulatory reasons. Plant-based milks haven’t been studied as extensively in this context, but since they don’t contain casein, they likely don’t have the same blocking effect. A squeeze of lemon, which some research suggests may actually help preserve polyphenol activity, is another option. If you enjoy milky tea, you’re still getting the caffeine and the warmth — just probably not the vascular benefits.
The Long-Term Payoff of Regular Tea Drinking
Most of the studies above measure what happens in the hours after a single cup. But the long-term picture is where things get particularly compelling for cardiovascular health. Arterial stiffness is a key marker of vascular aging — stiff arteries force the heart to work harder and contribute to high blood pressure and organ damage.
In a large cross-sectional study of over 6,000 Chinese adults, people in the highest tea-consumption group had about a 22% lower risk of falling into the worst quartile for arterial stiffness, even after adjusting for age, smoking, exercise, cholesterol, obesity, and blood pressure.15PubMed Central. Increased Tea Consumption Is Associated with Decreased Arterial Stiffness in a Chinese Population
A separate study looked specifically at duration and dose. The results were striking on both counts: people who had been habitual tea drinkers for more than six years, consuming more than 10 grams of tea leaves per day, had measurably more flexible arteries than non-drinkers. Habitual tea consumption was associated with about 37% lower odds of arterial stiffness overall.16PubMed. A Cross-sectional Study of the Relationship Between Habitual Tea Consumption and Arterial Stiffness And the association was dose-dependent: more years of tea drinking and more tea per day correlated with more flexible blood vessels.
These are observational studies, so they can’t prove tea caused the benefit. People who drink tea daily for a decade may also have other healthy habits. But the consistency of the finding across different populations, and the dose-response pattern, makes it more persuasive than a single snapshot would be.
When the Real Problem Is Cold Hands and Feet
Poor circulation to the extremities is probably the most common complaint people hope tea will fix. If your hands and feet are chronically cold, the issue could be Raynaud’s phenomenon (where small arteries in the fingers and toes spasm in response to cold or stress) or simply a constitutional tendency toward peripheral vasoconstriction.
Ginger tea is the most direct herbal option here, given its demonstrated peripheral warming effect. But a systematic review of herbal medicines for cold hypersensitivity in the hands and feet found broader support. Across 13 studies, herbal treatments significantly reduced symptoms of cold extremities and Raynaud’s phenomenon compared to no treatment or conventional medicine alone. In the one study that used a proper placebo arm, herbal treatment was superior in raising both skin temperature and peripheral blood flow.17PubMed Central. Herbal Medicines for Cold Hypersensitivity in the Hands and Feet: A Systematic Review and Meta-Analysis
The herbal formulas in that review were mostly traditional multi-herb preparations rather than single-ingredient teas, so you can’t directly extrapolate to a simple cup of ginger or cinnamon. Still, the direction is consistent: warming herbs with vasodilatory or thermogenic properties can meaningfully help with peripheral circulation. A blend of ginger, cinnamon, and maybe a pinch of cayenne is a folk remedy that, while not rigorously tested as a package, combines ingredients with individually supported mechanisms.
Interactions with Blood-Thinning Medications
If you take warfarin or another anticoagulant, some herbal teas deserve real caution. Because many tea compounds have mild anti-clotting or blood-vessel-affecting properties, combining them with prescription blood thinners can tip the balance toward excessive bleeding.
A case report documented a possible interaction between peppermint herbal tea and warfarin, in which the tea appeared to amplify the drug’s anticoagulant effect.18Reviews in Clinical Medicine. Possible interaction of warfarin with peppermint herbal tea: a case report More broadly, a review of herb-warfarin interactions classified several herbs commonly consumed as teas — including ginkgo, chamomile, and cranberry — as having potentially major interactions with warfarin.19PubMed Central. Updates on the clinical evidenced herb-warfarin interactions
Green and black tea present a different concern: their vitamin K content. Vitamin K works in the opposite direction from warfarin, so large or wildly inconsistent amounts of tea could make warfarin dosing unpredictable. The practical advice for anyone on anticoagulants is to keep your tea consumption relatively steady from day to day rather than bouncing between zero and six cups, and to let your prescriber know what you’re drinking regularly. This is especially true for ginkgo biloba, which has both antiplatelet and blood-flow-enhancing properties that could compound the effects of prescription anticoagulants.
Why Whole Tea Tends to Beat Supplements
One theme runs through much of this research: brewed tea tends to outperform isolated extracts and capsules. The green tea study that found EGCG supplements ineffective while brewed tea worked is the clearest example, but the pattern echoes elsewhere. Black tea’s vascular metabolites are partly created by gut bacteria breaking down the full matrix of compounds in the tea — a process a purified extract might not replicate. Hawthorn’s vasodilation involved a cascade from nitric oxide to prostacyclin that likely depends on the full spectrum of compounds in the berry rather than a single isolated fraction.
This doesn’t mean every tea supplement is worthless. Ginkgo biloba’s blood flow effects, for instance, have been demonstrated with standardized extract rather than a traditional brew. But for green and black tea specifically, the evidence leans toward the cup over the capsule. The water extraction process, the temperature, and the interaction of multiple polyphenols together seem to matter in ways that manufacturers haven’t fully replicated. If you’re going to drink tea for your circulation, the simplest and best-supported approach is also the most enjoyable one: brew it, skip the milk, and drink it regularly.