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If you want just one fast takeaway about green tea that you probably won’t forget, here it is: It could save your life. No kidding. In a study that followed more than 40,000 adults in Japan for 11 years, those who drank 5 or more cups each day were significantly less likely to die. Period.
But green tea’s resume goes even deeper and wider. It’s absolutely loaded with catechins, flavones, and flavonols, biochemicals that exhibit antioxidant, anti-inflammatory, and anticancer activities. Green tea also has a positive effect on both diabetes and obesity. One particular compound in green tea—epigallocatechin gallate (EGCG)—has shown remarkable promise for fat burning and is even sold in supplement form as a weight loss aid. It inhibits the proliferation of fat cells, increases fat burning, and even increases energy expenditure.
Green tea—and the cornucopia of polyphenols it contains—has long been associated with weight loss through a variety of mechanisms. One of these may be that it helps stimulate the production of brown fat, which is associated with fat burning in the human body.
For a long time, we’ve thought that amazing foods—green tea, broccoli, kale, red wine—did most of their work by being powerful antioxidants and anti-inflammatories, and for the most part, that’s true. But now we’re finding that these compounds help the body at an even deeper level that can’t be explained by its antioxidant and anti-inflammatory properties alone.
Within just about every cell in the body are structures called mitochondria—ground zero for energy production, fat burning, and other metabolic processes. Green tea helps repair and strengthen mitochondria by activating mechanisms that force the cell to make protective enzymes that ultimately stimulate production of more mitochondria. And healthy, functioning mitochondria lead to a healthy metabolism, which leads to more energy, greater clarity, and even weight loss.
Note on caffeine: All the great studies on green tea were done on the caffeinated version, and it’s worth noting that green tea drinkers rarely get the jitters that coffee drinkers do. That’s because green tea contains an amino acid called L-theanine, which is one of nature’s great relaxers. It produces a sense of calm and focus that offsets the jittery effects of caffeine.