Tag Archives: green tea

Another Reason to Drink Green Tea: Lower Incidence of Kidney Stones

In a Chinese population, green tea consumption was linked to 15-20% lower risk of kidney stones:

“During 319 211 and 696 950 person-years of follow up, respectively, 1202 men and 1451 women reported incident stones. Approximately two-thirds of men and one-quarter of women were tea drinkers at baseline, of whom green tea was the primary type consumed (95% in men, 88% in women). Tea drinkers (men: hazard ratio 0.78, 95% confidence interval 0.69-0.88; women: hazard ratio 0.8, 95% confidence interval 0.77-0.98) and specifically green tea drinkers (men: hazard ratio 0.78, 95% confidence interval 0.69-0.88; women: hazard ratio 0.84, 95% confidence interval 0.74-0.95) had lower incident risk than never/former drinkers. Compared with never/former drinkers, a stronger dose-response trend was observed for the amount of dried tea leaf consumed/month by men (hazard ratiohighest category 0.67, 95% confidence interval 0.56-0.80, Ptrend  < 0.001) than by women (hazard ratiohighest category 0.87, 95% confidence interval 0.70-1.08, Ptrend  = 0.041).

CONCLUSIONS:Green tea intake is associated with a lower risk of incident kidney stones, and the benefit is observed more strongly among men.”

Source: Green tea intake and risk of incident kidney stones: Prospective cohort studies in middle-aged and elderly Chinese individuals. – PubMed – NCBI

Bix Reports: Tea And Apples Are Good For The Heart 

Green tea

Green tea

The healthful component of tea and apples seems to be epicatechins. Bix, the Fanatic Cook, writes:

“Other good sources of epicatechins, besides apples and tea, include blackberries, broad beans, cherries, black grapes, pears, raspberries, and chocolate. Red wine also contains epicatechins….”

Source: New Study: Tea And Apples Are Good For The Heart | Fanatic Cook

Bix worries about the alcohol in wine causing cancer. Keep your consumption low to moderate and cancer shouldn’t be a problem.

TeaGuardian.com says green and white teas have the most catechins (same as epicatechins, I assume for now).

The study at hand involved Dutch men, so we don’t know if results apply to women. It’s an observational study. The men with the highest epicatechin consumption had a 38% lower risk of death from coronary heart disease compared to the lowest consumers. Perhaps because it was a relatively small study involving only Dutch men, the researcher write that “More studies are needed before conclusions can be drawn.

Steve Parker, M.D.

PS: Have you heard that the Mediterranean diet is also good for your heart?

Why Is My Green Tea Brown?

At least the box is green

At least the box is green

I’ve been reading for years how green tea is or might be particularly healthful for us. It’s not just hearsay. Respected journals like the American Journal of Clinical Nutrition suggest green tea’s virtues: longevity and less risk of type 2 diabetes, heart disease, and dementia, to name a few off the top of my head.

I’ve never been a tea drinker. Oh, sure, I’ve drunk iced tea at restaurants now and then. That’s black tea.

I drink coffee, about five cups a day. I work a fair number of night shifts, and the caffeine helps wake me up and keep me alert.

On a lark recently, I thought I’d cut back on the coffee and try green tea. In case you’re wondering, green tea has a third of the caffeine content of coffee.

So I go to the supermarket tea section and pick up a box of Bigelow green tea bags. There were five or 10 other options. Why Bigelow? I think I’ve heard the name before. Or the box appealed to me subconsciously. I brew it up easy-peasy per directions and this is what I see:

Mild, pleasant flavor but may not have the phytonutrients I seek

Mild, pleasant flavor but may not have the phytonutrients I seek

WTF?!

Does that look green to you?

I didn’t think so.

Naturally I start googling. The rest of this paragraph may or may not be true, like everything you read on the Internet. Green tea by tradition should be green. The supermarket teas are not traditional. They are oxidized, not fresh, or processed incorrectly. They’re a bastardization of traditional green teas with primary goals of mass distribution and adequate shelf life. They don’t have much of the “healthy” components you are looking for: anti-oxidants, polyphenols, EGCG, catechins, etc. Phytonutrient content of teas varies from batch to batch. The epidemiological studies that support green tea as healthful involved mostly Asian populations, often Japanese, who were drinking traditional green tea that’s green. Brewing is important: 170°F (77°C) for no more than 2–3 minutes. The fresher the tea leaves, the better. Special packaging may help preserve freshness. A Japanese-sounding brand may use tea grown outside of Japan.

I don’t know any avid green tea drinkers. So I go to Amazon.com and start reading reviews. Apparently there’s a whole world of green tea culture and I’ve just scratched the surface. I’ve already spent three hours on this green tea thing. Judging from Amazon reviews, here are some green teas that might be worth trying: Kirkland Ito En Matcha Blend Japanese Green Tea Bags and Yamamotoyama Green Tea—Sushi Style. (Kirkland is a Costco brand.) (See update below for more teas.) I probably also need to seek out a local Japanese ethnic food store and see what they’ve got or recommend.

I’m not raggin’on Bigelow green tea specifically. I bet most supermarket green teas in the U.S. will come out brown. For all I know, Bigelow may be jam-packed with healthy phytonutrients that will help you live to 110. It has a mild pleasant taste that I enjoyed. I didn’t miss the higher caffeine load of coffee. But it’s not traditional green tea.

I still want to try a green tea habit. If you can give me some pointers, please do so below or email me at steveparkermd AT gmail DoT com. (Do we still have to hide email addresses from bots?)

Steve Parker, M.D.

PS: Just because green tea may be healthful for Southeast Asians, that’s no guarantee it works for other ethnicities.

PPS: I’m not at all convinced that green tea is a panacea that will help me stay healthy or live longer.

PPPS: Green tea is one of Franziska Spritzler’s low-carb beauty foods.

Update July 1, 2016: Camelopardalis on Twitter recommended Fuijukyu loose leaves. I’m also reading good reviews on Jade Leaf Matcha Ceremonial Grade tea.

Steve Parker MD, Advanced Mediterranean Diet

Two diet books in one