Growing up, tea drinking was reserved for my grandmother’s visits. Making it followed a strict and fascinating ritual. Take scalding hot water. Warm the tea pot. Add one spoon of tea leaves for each person and one for the pot. Cover with a tea cosy. Turn the pot three times to the left, three to the right, then three to the left. Leave to brew. Warm the cups; milk in first, pour through a tea strainer.
My grandmother could taste any attempt you made to shortcut the process. Once Grandma approved the tea, pressure eased and conversation flowed.
In Australia 38% of the general population and 67% of those aged over 70 are tea drinkers. Our median intake is two cups a day, about 400mls.
By world standards we rank 55 for tea consumption, compared to the United States at 69, New Zealand 45 and the United Kingdom, number five. Turkey takes out the number one spot, consuming more than ten times the per capita intake of Australians.
1. Tea and survival
Around the world, tea is the most common drink after water. Popularity increased in the 1800s because the practise of boiling water to make the tea meant water-borne pathogens like cholera and typhoid would be killed, making it safer to drink.
Science has muscled in on our tea drinking habits and started to unravel what makes us love our “cuppa”. There is a large group of bioactive components in tea called polyphenols, which include catechins and tannins. Concentrations of these compounds vary depending on how you make the tea, including the amount of tea leaves per cup, water temperature and brewing time.
Catechins have anti-oxidant properties and are most abundant in green tea. Tannins, which inhibit non-haem iron absorption in the gut, are most abundant in black tea. So if you have iron deficiency, avoid drinking tea with meals. But if you have the excessive iron storage condition haemochromatosis, drinking tea with meals will help reduce iron absorption.
2. Tea and your brain
Components of tea that can boost brain activity include caffeine, catechins and the amino acid, L-theanine.
In a systematic review of the effects of tea on mood and cognitive function, the combination of L-theanine and caffeine was shown to increase alertness and attention-switching accuracy up to two hours after consumption. The researchers also found small enhancements in accuracy of visual and auditory attention.
Preliminary evidence also suggests catechins may have a calming effect during the second hour post-cuppa. The authors called for further research using a greater dosage range of catechin and L-theanine to help separate any effects due to caffeine intake.
At this stage however, there is no clear evidence that drinking tea will protect people from developing dementia.
3. Tea and weight loss
There has been a lot of interest in whether tea, particularly green tea, can increase energy expenditure and help with weight loss.
Two Dutch meta-analyses have examined the evidence in studies comparing catechin-plus-caffeine mixtures versus caffeine-only supplements on energy expenditure and fat oxidation (breaking down fat). They found that compared to placebo and caffeine-only groups, people who had catechin-plus-caffeine mixtures were more likely to break down fat.
They also evaluated whether green tea could improve body weight regulation. Their meta-analysis found the group consuming catechins from green tea had a 1.3 kilogram greater weight loss and were more likely to maintain this loss; although there were some differences based on ethnicity and usual caffeine intake.
Health news in pictures
Health news in pictures
1/22 New online test predicts skin cancer risk
Health experts have created a new online tool which can predict a person’s risk of developing a common form of skin cancer. The tool uses the results of a 10-question-quiz to estimate the chance of a person aged 40 or over of having non-melanoma skin cancers within three years. Factors including the age, gender, smoking status, skin colour, tanning ability, freckling tendency, and other aspects of medical history are covered by the quiz
2/22 Multiple Sclerosis stem cell treatment 'helps patients walk again'
A new treatment for multiple sclerosis (MS) has enabled some patients to walk again by “rebooting” their immune systems. As part of a clinical trial at Sheffield's Royal Hallamshire Hospital involving around 20 patients, scientists used stem cells to carry out a bone marrow transplant. The method known as an autologous haematopoietic stem cell transplant (HSCT) works by using chemotherapy to destroy the area of the immune system which causes MS
3/22 Dementia patients left without painkillers and handcuffed to bed
Dementia patients experience a ‘shocking’ variation in the quality of hospital care they receive across England, a charity has warned. Staff using excessive force and not giving dementia patients the correct pain medication were among the findings outlined in a new report by The Alzheimer’s Society, to coincide with the launch of Fix Dementia Care campaign
4/22 Cancer risk 'increased' by drinking more than one glass of wine or pint of beer per day
Drinking more than one glass of wine or pint of beer a day increases the risk of developing cancer, according to medical experts. New guidelines for alcohol consumption by the UK published by chief medical officers warn that drinking any level of alcohol has been linked to a range of different cancers. The evidence from the Committee on Carcinogenicity (COC) overturns the oft-held view that a glass of red wine can have significant medical benefits for both men and women
5/22 Vaping 'no better' than smoking regular cigarettes
Vaping could be “no better” than smoking regular cigarettes and may be linked to cancer, scientists have found. The study which showed that vapour from e-cigarettes can damage or kill human cells was publsihed as the devices are to be rolled out by UK public health officials as an aid to quit smoking from 2016. An estimated 2.6 million people in the UK currently use e-cigarettes
6/22 Rat-bite fever
A teenager was hospitalised and left unable to move after she developed the rare rat-bite fever disease from her pet rodents which lived in her bedroom. The teenager, who has not been named, was taken to hospital after she complained of a pain in her right hip and lower back which later made her immobile, according to the online medical journal BMJ Case Reports. She suffered for two weeks with an intermittent fever, nausea and vomiting and had a pink rash on her hands and feet. The teenager, who had numerous pets including a dog, cat, horse and three pet rats, has since made a full recovery after undergoing a course of antibiotics. Blood tests showed that she was infected with for streptobacillus moniliformis – the most common cause of rat-bite fever. One of her three pet rats lay dead in her room for three weeks before her symptoms showed
7/22 Taking antidepressants in pregnancy ‘could double the risk of autism in toddlers’
Taking antidepressants during pregnancy could almost double the risk of a child being diagnosed with autism in the first years of life, a major study of nearly 150,000 pregnancies has suggested. Researchers have found a link between women in the later stages of pregnancy who were prescribed one of the most common types of antidepressant drugs, and autism diagnosed in children under seven years of age
8/22 Warning over Calpol
Parents have been warned that giving children paracetamol-based medicines such as Calpol and Disprol too often could lead to serious health issues later in life. Leading paediatrician and professor of general paediatrics at University College London, Alastair Sutcliffe, said parents were overusing paracetamol to treat mild fevers. As a result, the risk of developing asthma, as well as kidney, heart and liver damage is heightened
9/22 Fat loss from pancreas 'can reverse' effects of type-2 diabetes
Less than half a teaspoon of fat is all that it takes to turn someone into a type-2 diabetic according to a study that could overturn conventional wisdom on a disease affecting nearly 3 million people in Britain. Researchers have found it is not so much the overall body fat that is important in determining the onset of type-2 diabetes but the small amount of fat deposited in the pancreas, the endocrine organ responsible for insulin production
10/22 Potatoes reduce risk of stomach cancer
Scientists have found people who eat large amounts of white vegetables were a third less likely to contract stomach cancer. The study, undertaken by Chinese scientists at Zhejiang University, found eating cauliflower, potatoes and onions reduces the chance of contracting stomach cancer but that beer, spirits, salt and preserved foods increased a person’s risk of the cancer
11/22 Connections between brain cells destroyed in early stages of Alzheimer’s disease
Scientists have pinpointed how connections in the brain are destroyed in the early stages of Alzheimer’s disease, in a study which it is hoped will help in the development of treatments for the debilitating condition. At the early stages of the development of Alzheimer’s disease the synapses – which connect the neurons in the brain – are destroyed, according to researchers at the University of New South Wales, Australia. The synapses are vital for brain function, particularly learning and forming memories
12/22 Sugar tax
The Government should introduce a sugar tax to prevent an “obesity crisis” from crippling the NHS, a senior Conservative MP and former health minister has said. Dr Dan Poulter believes that the case for increased taxes on unhealthy sugary products was “increasingly compelling”
13/22 Cancer breakthrough offers new hope for survivors rendered infertile by chemotherapy
A potentially “phenomenal” scientific breakthrough has offered fresh hope to cancer patients rendered infertile by chemotherapy. For the first time, researchers managed to restore ovaries in mice affected by chemotherapy so that they were able to have offspring. The scientists now plan to begin clinical trials to see if the technique, which involves the use of stem cells, will also work in humans by using umbilical cord material and possibly stem cells taken from human embryos, if regulators agree
14/22 Take this NHS test to find out if you have a cancerous mole
An interactive test could help flag up whether you should seek advice from a health professional for one of the most common types of cancer. The test is available on the NHS Choices website and reveals whether you are at risk from the disease and recommends if you should seek help. The mole self-assessment factors in elements such as complexion, the number of times you have been severely sunburnt and whether skin cancer runs in your family. It also quizzes you on the number of moles you have and whether there have been any changes in appearance regarding size, shape and colour
15/22 Health apps approved by NHS 'may put users at risk of identity theft'
Experts have warned that some apps do not adequately protect personal information
16/22 A watchdog has said that care visits must last longer
The National Institute for Health and Care Excellence (Nice) said home help visits of less than 30 minutes were not acceptable unless part of a wider package of support
17/22 Pendle in Lancashire tops list of five most anxious places to live in the UK
Pendle in Lancashire has been named the most anxious place to live in the UK, while people living in Fermanagh and Omagh in Northern Ireland have been found to be the happiest
18/22 Ketamine could be used as anti-depressant
Researchers at the University of Auckland said monitoring the effects of the drug on the brain has revealed neural pathways that could aid the development of fast-acting medications. Ketamine is a synthetic compound used as an off anaesthetic and analgesic drug, but is commonly used illegally as a hallucinogenic party drug. Dr Suresh Muthukumaraswamy, a senior researcher at the university and a member of the institution’s Centre for Brain Research, used the latest technology in brain imaging to investigate what mechanisms ketamine uses to be active in the human brain
19/22 A prosthetic hand that lets people actually feel through
The technology lets paralysed people feel actual sensations when touching objects — including light taps on the mechanical finger — and could be a huge breakthrough for prosthetics, according to its makers. The tool was used to let a 28-year-old man who has been paralysed for more than a decade. While prosthetics have previously been able to be controlled directly from the brain, it is the first time that signals have been successfully sent the other way
20/22 The biggest cause of early death in the world is what you eat
Unhealthy eating has been named as the most common cause of premature death around the globe, new data has revealed. A poor diet – which involves eating too few vegetables, fruits, nuts and grains and too much red meat, salt and sugar - was shown to be a bigger killer than smoking and alcohol
21/22 Scientists develop blood test that estimates how quickly people age
Scientists believe it could be used to predict a person’s risk of developing Alzheimer’s disease as well as the “youthfulness” of donated organs for transplant operations. The test measures the vitality of certain genes which the researchers believe is an accurate indication of a person’s “biological age”, which may be younger or older than their actual chronological age
22/22 Aspirin could help boost therapies that fight cancer
The latest therapies that fight cancer could work better when combined with aspirin, research has suggested. Scientists from the Francis Crick Institute in London say the anti-inflammatory pain killer suppresses a cancer molecule that allows tumours to evade the body’s immune defences. Laboratory tests have shown that skin, breast and bowel cancer cells often generate large amounts of this molecule, called prostaglandin E2 (PGE2). But Aspirin is one of a family of drugs that sends messages to the brain to block production of PGE2 and this means cancer cells can be attacked by the body’s natural defences
4. Tea and diabetes
Last year, a pooled analysis of 12 cohort studies compared tea drinking with risk of type 2 diabetes. Researchers found that among those who drank three to four or more cups per day there was a 16% lower risk of developing type 2 diabetes, compared to those who usually drank just one or no cups of tea.
But when they drilled down into the studies, the lower risk was only found in women and those of Asian ethnicity. We need to keep in mind that associations found in cohort studies do not prove causation.
In a meta-analysis of ten randomised controlled trials that lasted eight weeks or more, totalling 608 adults with type 2 diabetes, researchers found mixed results for the impact of drinking tea, or consuming various tea extracts, on blood markers of diabetes control.
While there were improvements in fasting blood insulin and waist circumference, there was no impact on other markers, including fasting blood glucose, LDL (bad) or HDL (good) cholesterol, body mass index or blood pressure.
Researchers are now focusing more closely on the phenolic components in tea to try and develop compounds that could be used to prevent or manage type 2 diabetes.
5. Tea and heart disease
A Cochrane review evaluated 11 randomised controlled trials that ran for at least three months and were aimed at preventing heart disease in healthy adults or those at high risk of heart disease.
Pooled results showed that both green tea and black tea significantly reduced blood pressure, with black tea lowering LDL-cholesterol and green tea lowering total cholesterol. The small number of studies to date though means these results need to be interpreted with caution, but they do look promising.
Meanwhile, for a host of other reasons it seems that my grandmother was right: a good brew does more than than just warm you up (or cool you down). So put the kettle on, get out your best tea cups, create your own tea making ritual, gather the clan and relax with a cuppa.