Blood flow can be slowed or restricted by a buildup of plaque in the arteries, leading to a reduction in oxygen uptake. Sometimes poor circulation is a symptom of high blood pressure, high cholesterol or heart disease. Some herbs, which can be boiled and strained to become a tea, encourage blood flow. Sweeten teas with honey or other sweeteners to enjoy daily if approved by your doctor. Herbs can interact with certain medications and with other herbs. Before drinking herbal teas, talk with your doctor if you're on medication, have a health condition, or are pregnant or breastfeeding.
Ginger tea may relax the muscles around blood vessels, allowing blood to circulate better. According to a study published in 2010 in "Current Cardiology Reviews," gingerol is the active ingredient in ginger responsible for relaxing blood vessels, stimulating blood flow and even potentially reducing pain. The scientists concluded that ginger may have the potential to improve cholesterol levels and lower your risk of heart disease. Another study, published in "Life Sciences" in 2002, demonstrated that dried ginger increased intestinal blood flow in rats without affecting blood pressure.
Garlic has been found to dilate blood vessels by increasing the body's production of nitric oxide, allowing for increased blood flow. In a study published in "The Journal of Nutritional Biochemistry" in 2004, scientists gave healthy female volunteers 600 milligrams of garlic daily for seven days, and a group of the same age and body mass index as the garlic group received a placebo. They measured the rate of tissue blood flow in calf muscles of all volunteers while at rest, and before and after administering garlic. After seven days, the placebo group had no change in blood flow, while the garlic group demonstrated significantly increased circulation.
Chinese Hawthorn Tea
According to an article published in "Pharmacognosy Review" in 2011, Chinese hawthorn is an herb used in China to increase circulation and lower blood pressure. It's also traditionally used to treat heart disease, but modern clinical trials are inconsistent with dosage criteria. According to a different article published in "Pharmacognosy Review" in 2010 that assessed research on Chinese hawthorn in treating heart disease, research to date suggests that hawthorn may be safe and effective, but further study is needed. In one study, Chinese hawthorn displayed a blood-thinning effect that inhibited blood clot formation in mice within 24 hours. However, this was administered as an ethanol extract of hawthorn, and the effects of hawthorn tea on human circulation haven't been determined.
Gingko Biloba Tea
Ginkgo biloba is an herb that's been found to increase blood flow to the brain, but improved circulation in other parts of the body has not been confirmed. In a study published in "Neuroradiology" in 2011, healthy older male volunteers were administered 60 milligrams of ginkgo biloba extract twice daily for a month. They were given MRI brain scans before and after. At the end of the month, the brain scans showed that there was a significant increase in blood flow to their brains. Ginkgo biloba has negative interactions with several medications, including monoamine oxidase inhibitors, warfarin, nifedipine, alprazolam and haloperidol. Research has not determined the effects of gingko tea vs. gingko extract, optimal dosage or long-term side effects.