That moment in the morning when tea drinkers take their first warm sip can be amazing. And now, 12 new articles from the American Journal of Clinical Nutrition show that tea may indeed be a magical elixir, as it was shown to promote weight loss, prevent chronic illnesses and improve mood.
Tea is the second most consumed beverage in the world, according to the Tea Association, beaten only by water. Though there have been a multitude of studies about antioxidants in tea and the resulting human health effects, these recent studies in the American Journal of Clinical Nutrition (AJCN) shed light on just how helpful tea is for our health.
Experts from the US Department of Agriculture, National Institutes of Health, UCLA and the University of Glasgow – among others – contributed to the AJCN body of evidence.
Jeffrey Blumberg, PhD, compendium editor for the issue, says:
“The scientists who contributed their original research and insights are among the best in the world, and together, this body of research has significantly advanced the science of tea and human health.”
Tea and weight loss
Along with promoting weight loss, studies found that drinking tea reduces cancer and cardiovascular risks and it also provides psychological benefits.
Researchers who looked at polyphenols – natural compounds in tea – found that they, along with the caffeine content, increased energy expenditure and fat oxidation, which resulted in weight loss and helped maintain a healthy body weight.
One study shows that subjects who consumed green tea and caffeine lost an average of 2.9 pounds over 12 weeks, all while maintaining their normal diet.
Other studies show that regular tea drinkers have lower body mass indexes (BMIs) and waist-to-hip ratios, along with less body fat, compared with non-tea drinkers.
Additionally, another review showed that the increase in calories burned as a result of drinking tea equates to around 100 calories during a 24-hour period.
Reduced cancer and cardiovascular risks
Another set of researchers found that the polyphenols in green tea may help to stop the progression of certain cancers.
In one study, scientists observed that after a year, 30% of men in a placebo group progressed to prostate cancer, compared with only 9% of men who were in a tea-supplemented group.
Other cancers for which tea provides protective health benefits are cancers of the gastrointestinal tract, lung, breast and skin, researchers say.
A study conducted by Dr. Claudio Ferri in Italy showed that black tea reduced blood pressure in patients with hypertension and also neutralized negative effects of high-fat meals on arterial blood flow and blood pressure.
Dr. Ferri comments on his findings:
“Our studies build on previous work to clearly show that drinking as little as one cup of tea per day supports healthy arterial function and blood pressure. These results suggest that on a population scale, drinking tea could help reduce significantly the incidence of stroke, heart attack and other cardiovascular diseases.”
Improved bone strength, alertness and problem solving
Another benefit of the polyphenols in green tea includes improving bone quality and strength, particularly in the wake of osteoporosis.
Tea drinking in one study was associated with a 30% reduced risk of hip fractures in men and women aged 50 years or older.
And if that fails to put individuals in a good mood, drinking tea will. In one study in particular, drinking tea was found to improve attention and facilitate better focus on tasks.
Subjects in the study drank 2-3 cups of tea within 90 minutes, and this resulted in more accurate results during an attention task and feelings of being more alert, compared with subjects drinking a placebo.
Researchers note that the amino acid theanine and caffeine in tea are thought to confer psychological benefits to drinkers, strengthening attention, mood and performance.
“Humans have been drinking tea for some 5,000 years, dating back to the Paleolithic period,” says Prof. Blumberg. “Modern research is providing the proof that there are real health benefits to gain from enjoying this ancient beverage.”
Written by Marie Ellis