Can tea reduce stroke risk?
Heidi Moawad, MD
Did you know that regularly drinking tea has been associated with a lower risk of stroke? Scientific studies using large research databases evaluated the tea drinking habits of over 500,000 people from different regions throughout the world, and the results showed that there was a 13 percent lower risk of stroke among tea drinkers.
How much tea is associated with decreased stroke?
The studies revealed the
noticeable 13 percent decline in stroke risk among the tea drinkers who reported drinking 3 cups of tea per day.
This conclusion came from an 11-year follow-up suggesting that the effect of tea on stroke risk is a long-term effect, not a short-term one.
There was no noticeable decline in stroke risk among participants who only occasionally drank tea.
What kind of tea?
There are hundreds of available varieties and blends of tea. Most of the studies did not specifically differentiate which type of tea was associated with deceased stroke.
However, one of the smaller research studies did try to identify which type of tea is more beneficial. The researchers compared 940 people who had hemorrhagic strokes with 940 healthy volunteers. The results of that research suggested that green tea consumption was associated with a deceased stroke rate but that black tea consumption was not.
However, this singling out of a specific kind of tea should be taken with a grain of salt, because even green tea itself is not necessarily pure, and often green tea is mixed with other tea.
Overall, based on the larger studies, it appears that drinking tea is associated with decreased hemorrhagic and ischemic stroke, but particular varieties still need to be studied in more detail.
Why does tea help in stroke prevention?
Many kinds of tea contain some antioxidants. Antioxidants are more concentrated in tea that is produced using natural tea leaves or natural fruit, such as mango or raspberry.
The only problem is that if a tea says mango or raspberry on the box, you cant be sure that actual fruit was used or whether the manufacturers simply enhanced the tea with fruit-colored and fruit-flavored additives.
Some tea varieties are herbal tea, which generally do not contain caffeine and therefore hydrate the body while providing some antioxidants from the herbs that flavor them. Hydration itself is an important component of a healthy lifestyle and that might be partially responsible for some of the stroke-reducing properties of tea.
At the same time, the caffeinated varieties also have some
different stroke-fighting properties of their own.
In moderate amounts, caffeine is actually beneficial for the blood flow and blood vessels, and can therefore help prevent stroke in people who do not have problems with high blood pressure. Drinking more than 5 cups (approximately 8 ounces each) of caffeinated beverages per day, however, is dehydrating and unhealthy for most of the body, including the kidneys.
Are any kinds of tea harmful?
One the other hand, tea that is made with ginger or ginseng can be healthy in low to moderate doses, due to the blood thinning effects of ginger and ginseng. But, heavy consumption of more than 5-6 cups per day can result in too much of a blood thinning action, especially if you already take blood thinners. Instead of preventing stroke, this can lead to hemorrhagic stroke.
Overall, there are many research studies that link certain foods or drinks to increased or deceased stroke risk. Coffee, tea, chocolate, wine, and a number of cooking oils and foods have been found to help prevent stroke. Moderation and a well-rounded diet is really the key to a healthy stroke-free life.
Source: Verywell.com
