As a nation, Japan has the longest-living people in the world. They are also among the healthiest. Though there is no definitive answer for this longevity, the fact that their national diet contains a number of disease-fighting foods consumed daily is an obvious factor.
Take seaweed, for example. The Japanese eat about 4 to 6 grams of seaweed daily, covering a number of varieties. Also abundantly available – though overlooked – in this country, seaweed contains beneficial iodine and special disease-fighting compounds. Too unappealing to you, you say? How about fish? The Japanese consume a large portion of the world’s fish supply.
A Harvard University analysis of 20 studies involving hundreds of thousands of participants indicates that eating approximately one to two 3-ounce servings of fatty fish a week reduces the risk of dying from heart disease by 36 percent.
The Japanese diet is also full of numerous versions of fermented foods, which contain beneficial bacteria, yeast and nutrients. One form of fermented soy, called natto, I’ve written about before. It is considered a superfood by many because it is a rich source of vitamin K2, a nutrient hard to find in traditional American diets.
But the bellwether of the Japanese diet, as well as Japanese culture, is green tea. It may be the country’s biggest longevity factor. And given that I have done my “ode to coffee,” it is only fitting that I stop to take a fitting “bow to green tea” and its many health benefits.
Green tea is native to China and India. The first accounts of it in Japan date back to the ninth century. Japanese monks who traveled to China brought it back with them. Initially, it was consumed primarily as a medicine and was only available to those in the upper class.
At the time, green tea was used in China and India for a variety of medical treatments, from controlling bleeding and healing wounds to aiding digestion and regulating body temperature. Recent studies have validated many of these claims and more, as green tea has been shown to potentially have positive effects on everything from weight loss to liver disorders to Type 2 diabetes. Today Japanese green tea is produced in many localities, but about 44 percent of it is produced in Shizuoka prefecture, located about an hour south of Tokyo by the bullet train.
Though green tea contains more antioxidants than most other types of tea, it accounts for only 15 percent of the tea consumed in the U.S., according to recent statistics from the Tea Association of the USA. Black tea accounts for 84 percent of the tea we drink.
Among other indicators of green tea’s benefits, though not yet scientifically verified, is the fact that in countries where green tea consumption is high, cancer rates tend to be lower. In one large-scale clinical study done to investigate this phenomenon, drinkers of green tea were compared with nondrinkers of it.
Researchers found that those who drank the most tea were less likely to develop pancreatic cancer. This was particularly true with women, who were 50 percent less likely to develop the disease. Researchers believe that it is the high level of polyphenols, natural micronutrients found in tea that help kill cancerous cells and stop them from growing. The exact mechanism by which tea interacts with cancerous cells is still unknown, though it is believed that the components of green tea upset the metabolism of cancer cells. British researchers have also demonstrated that green tea – along with broccoli, turmeric and pomegranate – can help fight prostate cancer.
As stated in a study published in the journal Stroke, both coffee and green tea are believed to reduce the risk of stroke.
On another front, a 2006 study published in the Journal of the American Medical Association concluded that green tea consumption is associated with reduced mortality when it comes to all causes, including cardiovascular disease. This study, which began in 1994, followed more than 40,000 Japanese participants between the ages of 40 and 79 for 11 years. Participants who drank at least 5 cups of green tea per day were shown to have a significantly lower risk of dying than those who drank less than 1 cup of green tea per day. This was especially true when it came to cardiovascular disease.
According to Billie J. Sahley, executive director of the Pain & Stress Center, Japanese chemists may have come upon a major discovery in brain research in 1949 when they identified the amino acid theanine in green tea leaves. Theanine found in green tea is now being investigated as a protector of brain neurons, says Sahley, and for its properties causing not only a relaxing effect but also a sense of well-being. Green tea could also boost our working memory, according to new research published in the Journal of Psychopharmacology. Findings suggest that green tea can enhance the brain’s cognitive functions, particularly the working memory.
The key health-promoting ingredient in green tea is epigallocatechin gallate, known as EGCG. Green tea extracts standardized to EGCG are available as a dietary supplement. Theanine is also available in capsule form for those who want to reap the maximum benefits. To get what are considered maximum benefits from the beverage would require drinking about 5 or more cups of green tea daily.
There are little to no known side effects for adults who drink green tea. In some cases in which people have acute sensitivity to caffeine, insomnia, anxiety, irritability, nausea or upset stomach might occur, though green tea contains only a small amount of caffeine (approximately 20 to 45 milligrams per 8-ounce cup). People should also check with their doctors or health experts to make sure its use is compatible with supplements or medications they may be taking.
Write to Chuck Norris with your questions about health and fitness. Follow Chuck Norris through his official social media sites, on Twitter @chucknorris and Facebook’s “Official Chuck Norris Page.” He blogs at ChuckNorrisNews.blogspot.com.
