Tea, caffeine and blood pressure – good or bad?

A history of tea drinking

Tea has a long history, with the Chinese drinking it for thousands of years, originally for medicinal purposes. According to one Chinese myth, tea was discovered when the Emperor was drinking water that had just been boiled, and a few leaves blew into his bowl, surprising him with their pleasant taste….

In China, drinking tea has traditionally been associated with lower blood pressure, and studies have now shown that drinking even just half a cup of green or Oolong tea a day reduces the risk of developing high blood pressure. Australian and Iranian studies have shown that black tea can help lower blood pressure. And it’s fairly well established that drinking a couple of cups of tea a day lessens your risk of heart attack and stroke.

This is because tea contains a lot of antioxidants called polyphenols – and specifically, flavonoids – which have numerous health benefits for the cardiovascular system and metabolism.

These antioxidants help the heart and circulatory system, lowering cholesterol levels and protecting against artherosclerosis. The flavonoids in tea also seem to protect against some kinds of cancers.

The levels of antioxidants in black and green tea are even higher than those in many antioxidant-rich fruit and vegetables, and tea contains different types of antioxidants. A cup of green tea is estimated to contain 10 – 40 mg of polyphenols, which is more than a serving of an antioxidant-rich food like broccoli.

So as well as eating plenty of the good fruit and veg, drinking a few cups of tea a day will help ensure you’re getting a good, and wide-ranging, dose of antioxidants. Good for you all around!

Types of Tea – Black, Green and Oolong

All tea comes from the same plant – Camellia Sinensis – an evergreen bush native to China and India. The different ways the leaves are processed results in the different types of tea, with their different colours, flavours and properties. Green tea is heat-treated before fermentation occurs, while black tea is left to ferment, to develop its dark colour and stronger flavour. Oolong tea – known as red tea in China – is between the two.

The longer the tea is fermented, the higher its caffeine content and the lower its polyphenol content. So black tea contains 2-3 times the caffeine of green tea, and green tea has the highest level of polyphenols.

Caffeine does raise blood pressure, so be careful of drinking a lot of black tea if your daily caffeine levels are already substantial or if you notice you’re sensitive to the effects of caffeine. Switch to Oolong or green, which stimulate you more steadily. Decaffeinated tea is also available, and still contains all the polyphenols, and white tea – less popular due to its weak flavour – contains hardly any caffeine.

Tea and high blood pressure

So, while drinking any of these teas can help you reach and maintain a healthy blood pressure, green tea is the best bet – more antioxidants, less caffeine – and a bright refreshing taste that clears the mind and palate.

Less caffeine also makes green tea more hydrating, which is also good for blood pressure. And green tea contains catechins which stimulate the metabolism, helping the body burn fat. Since excess weight is also a factor in high blood pressure, green tea is good if you’re trying to lose weight.

So, try drinking at least 2-3 cups a day of green tea. Good for the body, good for the mind:).

Leave a Reply

Your email address will not be published. Required fields are marked *

24 visitors online now
22 guests, 2 bots, 0 members
Max visitors today: 45 at 12:36 am UTC
This month: 62 at 10-18-2014 03:11 am UTC
This year: 70 at 02-10-2014 06:41 pm UTC
All time: 229 at 11-21-2010 09:25 am UTC