Drinking green tea in the morning or early afternoon, combined with a suitable meal and avoiding taking it too late, can help take advantage of the potential benefits of this drink for cardiovascular health and blood pressure.
Green tea contains catechin, a group of plant compounds with antioxidant properties, which help protect blood vessels. Catechin can support the endothelial layer - the cell layer lining the blood vessels - to function better. Healthy endothelium contributes to the production of nitric oxide, a substance that helps dilate blood vessels and supports blood pressure control.
Should be drunk in the morning or early afternoon
There is no evidence that a specific time of day helps green tea lower blood pressure best. However, morning or early afternoon is considered a suitable time because green tea contains caffeine.
A 240 ml cup of green tea contains about 29-73 mg of caffeine, depending on the type. For sensitive people, caffeine can temporarily increase blood pressure or cause insomnia if taken too late.
Should not drink close to bedtime
Caffeine used at the end of the day can make it difficult to sleep or not sleep deeply. Prolonged sleep deprivation can make the sympathetic nervous system more active, causing heart to beat faster, blood vessels to constrict, and blood pressure to be difficult to control.
People sensitive to caffeine should limit green tea from the end of the afternoon, preferably finishing drinking 4-6 hours before bedtime. Some people may need to stop drinking after noon.
Limit drinking on an empty stomach
Green tea can cause nausea, heartburn or stomach discomfort in some people. Therefore, people with sensitive stomachs should drink it after a light snack.
Polyphenols in tea can also reduce iron absorption, especially iron from plants. Iron-deficient people should avoid drinking green tea right during iron-rich meals and can drink it about an hour before meals.
Drink moderately, do not change medicine
Green tea should only be considered part of a healthy diet, not a substitute for high blood pressure medication. The impact of green tea on blood pressure is usually not significant and long-term effectiveness still needs further research.
Healthy people can drink a few cups a day if they are tolerant. Drinking too much can cause restlessness, headache, rapid heartbeat or insomnia.
People taking blood pressure medication should continue treatment as prescribed and monitor blood pressure periodically. If you want to increase the amount of green tea or use products extracted from green tea, you should ask your doctor to avoid unwanted drug interactions.
