Food & Wine "Green tea extract promotes gut health, lowers blood sugar... "
"Green tea extract improves metabolic syndrome and gut health"
"Leaky gut: Green tea may help reduce gut inflammation, blood sugar"
Those were the headlines that hit my newsfeed a couple of weeks ago as people reported on a new study about green tea.
But don't run out to your local supplement store for a cart full of green tea extract. The study isn't as exciting as the news wants you to believe...
The study – from Ohio State University – measured the gut inflammation and glucose levels of participants over three months. Out of the participants, 21 had metabolic syndrome and 19 were classified as "healthy." Metabolic syndrome means you have at least three of the following:
- Abdominal obesity (excess weight you carry around your belly)
- High blood pressure
- High blood sugar
- High blood triglycerides
- Low levels of high-density lipoprotein (the "good cholesterol," or HDL)
For the first 28 days, researchers gave participants gummies with green tea extract that was the equivalent of five cups of green tea. The next 28, folks received a placebo, and then a placebo for the final 28 days.
Researchers found all participants showed a reduction in inflammation and glucose, though there were no immediate signs of a reversal in folks with metabolic syndrome.
Of course, longtime readers know I always read new studies with a critical eye. While I'm excited to see more research proving the vital importance of gut health, beware of misleading headlines...
This was an extremely small study over a very short time frame. For more concrete conclusions, we'll need to see a longer-term study in larger and more diverse groups of folks.
And always be wary of taking supplements based off the news media's reporting about new research. If you read on a mainstream-media site that a supplement "cures" some illness, do more research. (We too often see lots of misleading or incorrect reporting.) Or send it our way and we can dive into the topic... [email protected].
In this case, we've said before that too much green tea is dangerous.
Hospitals report that dietary supplements like green tea extract account for about 20% of all drug-related liver diseases.
Read that again... dietary supplements make up 20% of drug-related liver diseases.
The use of supplements is on the rise. Americans now spend more than $30 billion per year on nutritional supplements, according to the Nutritional Business Journal. The global supplement industry is worth more than $150 billion and is expected to grow nearly 9% a year for the next eight years.
While there is some regulation of supplements, the companies creating these pills are largely allowed to self-regulate.
In 1994, Congress passed the Dietary Supplement Health and Education Act. The act says, "The manufacturer of a dietary supplement or dietary ingredient is responsible for ensuring that the product is safe before it is marketed." This means the Food and Drug Administration ("FDA") doesn't verify claims made on labels or check the safety of products.
The FDA monitors complaints concerning supplements... But that's too little too late for folks who experience adverse side effects.
And green tea supplements are no different. They're often marketed as a way to lose weight, reduce your risk of cancer, and improve your heart health.
Research does show that drinking five to seven cups of actual green tea every week provides incredible health benefits.
Green tea is calorie-free, lowers cholesterol, fights cancer, and keeps immune systems strong. Green tea leaves are processed in a way that preserves many of the nutrients known to provide its health benefits.
Green tea also contains molecules called catechins. In brewed tea, the catechins are at a safe, diluted level.
However, extracts can contain high concentrations of catechins, which can cause liver damage. The severity of liver damage also worsens when you take green tea extract on an empty stomach, possibly because the catechins interact with glucose.
So dieters popping these pills while starving themselves are at a much higher risk of liver damage. If you or someone you know is taking green tea extract, throw it out immediately.
Instead, do what I do... Avoid fad pills and enjoy a cup of brewed green tea instead.
It takes some people a while to get used to the flavor. But I can tell you from personal experience that drinking tea is a relaxing and refreshing activity.
For best results (both for flavor and health benefits), you should drink green tea freshly brewed after allowing it to steep for three to five minutes.
True green-tea aficionados choose the loose leaves and a tea infuser over the prepackaged tea bags. The health benefits of loose green tea are much greater, due to the quality of the leaves. However, some great (and more convenient) green teas come in bag form.
If you want to do what I do, here's how I take my tea...
- I typically buy tea bags rather than loose-leaf tea. One of my favorite brands is Bigelow.
- I prefer Japanese sencha and jasmine flavors.
- I also buy and drink green teas that include other flavors from flowers and plants, which moderate green tea's sometimes-strong flavor.
- In the summer, I cook up a pot of tea and boil cranberries in another pot. Then I combine the liquids in a pitcher in the refrigerator for a delicious and naturally sweet iced tea. Year-round, I use a bit of honey to sweeten my tea.
Also, sipping tea can be the perfect time to sit quietly and meditate... even if for just 10 to 15 minutes a day. Meditation triggers a relaxation response that helps you live longer, and combining it with sipping green tea is a potent way to fight both stress and disease.
What We're Reading...
- The risk of green tea extract supplements.
- Something different: How to stop your endless doomscrolling.
Here's to our health, wealth, and a great retirement,
Dr. David Eifrig and the Health & Wealth Bulletin Research Team
August 11, 2022