RESEARCH CONTINUES TO REAFFIRM THE HEALTH BENEFITS OF TEA
Dr Tim Bond shares his advice on why drinking the humble cuppa is good for our health and wellbeing
Tea in all its forms remains Britain’s favourite drink. While we enjoy it, it is also great news for our wellbeing and published evidence continues to show the many health benefits packed into a cup of tea. Dr Tim Bond a tea health scientist and a member of the Tea Advisory panel (TAP) details his advice and tips as to why tea is good for our health and wellbeing:
- Diabetes – a growing number of studies have shown that people who drink three to four cups of black tea per day have a lower risk to type 2 diabetes than those who drink between zero and two cups per day. The protective effect of tea may be due to the variety of compounds present in tea, including the flavonoid antioxidants found in tea, which are known to help protect body cells from damage.
- Recent studies have also looked at the effect of black tea consumption on post-prandial blood glucose and insulin response following sugar consumption in normal and pre-diabetic subjects. In summary, the resulting data revealed that black tea consumption may improve blood glucose control following a meal. This may be due to black tea’s major bioactive compounds, the polyphenols.
- “The study was a randomized, double-blind, placebo-controlled crossover study. Twenty-four men and women aged 20-60 years, normal and pre-diabetic, randomly drank a sugar solution with a low dose of black tea polymerized polyphenol (BTPP), a high dose or a placebo drink. The drink containing both low dose and high dose BTPP significantly decreased blood glucose increase after sugar intake compared with placebo in both the normal and pre-diabetic subjects,” notes Dr Tim Bond. In summary, Dr Tim Bond notes: “This reduction in postprandial blood glucose after black tea was consumed with a sugar solution suggests that it is the polyphenols in black tea that are linked with this benefit. A 2016 meta-analysis of 10 studies found that tea or tea extract could help to maintain a stable fasting blood insulin level and reduce waist circumference in people with type 2 diabetes mellitus.”
- Hydration – contrary to popular belief tea is not dehydrating. In fact, it is an important source of fluid and both the Food Standards Agency and British Dietetic Association advise that drinking tea can help to meet daily fluid requirements (8 cups of fluid a day)
- Alertness – A number of studies have shown that ingredient compounds found in black tea, such as L-theanine and caffeine may improve our attention span. Dr Tim Bond, Tea Advisory Panel adds; ‘tea has been associated with many mental health benefits such as improved mental attention, clarity of mind and relaxation.
- Ageing and cognitive function - Emerging research suggests a benefit of tea in ageing and mental function. Studies indicate that the antioxidative impact of tea, likely due to its content of polyphenols, could have a beneficial effect on cognitive function following stroke and be beneficial in ageing.
“A study investigated the effect of green tea on short and long-term memory in the context of artificially induced stroke. Supplementation with green tea was initiated 10 days before stroke surgery and continued for six days after. The study subjects suffered short and long-term memory problems following stroke as well as oxidation of beneficial lipids in cell membranes related to oxidative stress. Green tea supplementation prevented this damage, indicating that green tea has a neuroprotective role in the brain and could therefore have a protective role in maintaining cognitive function following a stroke.
“In another study, which involved black tea, study subjects were supplemented with black tea to evaluate the impact of supplementation on the balance of oxidation or redox balance in the body. Redox status was evaluated at three stages of the subjects when they were young, middle aged and old. Black tea augmented redox status at all stages of the subjects lives, an effect likely due to the presence of catechins in black tea. This finding could have positive implications for ageing.”
In summary Dr Tim Bond notes: “Tea is the second most commonly consumed beverage in the world after water. As a result, published studies continue to suggest that Britain’s’ favorite beverage is good for our health including our bones, heart, vascular system and skin to name just a few health and wellbeing benefits, whatever your age.”
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Glycemic Control. Nutrients 2016;8(1).
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extract on metabolic profiles in patients
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 Bryan J. Psychological effects of dietary components of tea: caffeine and L-theanine. Nutr Rev 2008; 66:82–90.
 Redox (short for reduction–oxidation reaction) is a chemical reaction in which the oxidation states of atoms are changed. Any such reaction involves both a reduction process and a complementary oxidation process, two key concepts involved with electron transfer processes. Redox reactions include all chemical reactions in which atoms have their oxidation state changed; in general, redox reactions involve the transfer of electrons between chemical species. The chemical species from which the electron is stripped is said to have been oxidized, while the chemical species to which the electron is added is said to have been reduced.