Sunday, April 28, 2013

Australian research suggests that tea is good for blood pressure

It is hard to reconcile the claims in the article below with Prof. Hodgson's actual research findings, as published in 2013.  The first article of the year here showed no difference in day/night variability in BP but the second article, later on in the year here found that blood pressure was slightly less changeable at night among tea drinkers.  It looks like Prof. Hodgson squeezed his data until he got what he wanted. The data underlying the two contradictory articles  appear to be the same!

Furthermore a 2012 article, also by Prof. Hodgson, here showed a long-term difference between tea drinkers and controls of between 2 and 3 mmHg.  Totally trivial, in other words, close to the error of measurement.

The claims below are BS, to put it plainly.  Prof. Hodgson could throw away his teapot with no adverse consequences for his health

You might have thought you were simply satisfying a thirst in that most British of ways.  But drinking three cups of tea a day may also stabilise your blood pressure, researchers say.  It not only reduces blood pressure, but also minimises the variability of readings taken at night.

Experts say the benefits of tea are largely due to the flavonoid content - antioxidant ingredients that counteract cardio-vascular disease.

Every day there are 350 preventable strokes or heart attacks in the UK due to high blood pressure.  It has long been known that high blood pressure can significantly increase the risk of heart disease.

Now wide variations in blood pressure are also recognised as an important risk factor compared with readings that show little difference over a 24-hour period.

Professor Jonathan Hodgson of the University of Western Australia said: `There is already mounting evidence that tea is good for your heart health, but this is an important discovery because it demonstrates a link between tea and a major risk factor for heart disease.

`We have shown, for the first time to our knowledge, that the consumption of black tea can lower rates of blood pressure variation at night time.'

A survey last week found tea is still the nation's favourite drink, with Britons consuming 166 million cups of tea every day.

A high blood pressure reading is one that exceeds 140/90 millimetres of mercury (mm Hg).

The first figure, the systolic pressure, corresponds to the `surge' that occurs with each heartbeat.

In the latest study 111 men and women consumed three cups of black tea daily or a flavonoid free, caffeine containing beverage for six months.They had systolic blood pressure between 115 and 150 mm Hg.

The rate of blood pressure variation was assessed at three time points, on day one and at three and six months.

At these three time points, black tea consumption resulted in 10 per cent lower rates of blood pressure variability at night time than the flavonoid free drink.

These effects were seen immediately on the first day of tea drinking and maintained over the six months.

The study team believe coffee boosts the effects of the drug.

As the caffeine content of the two beverages was the same, the improvement in blood pressure variability would appear to be the result of a black tea component other than caffeine, says a report in the American Journal of Clinical Nutrition.

This is likely to be the flavonoid content, say the researchers, whose previous work found drinking three cups of tea daily led to a cut in blood pressure of between two and three mm HG.

Although black tea was drunk in the study, other research suggests adding milk does not affect the benefits.

Dr Tim Bond, from the industry-backed Tea Advisory Panel, said `High blood pressure is a well-recognised risk factor for cardiovascular and total mortality. Traditionally the level of blood pressure has been equated with risk but the variability of blood pressure is now also thought to contribute to risk.

`Black tea and its constituent flavonoids are increasingly associated with improvement in blood pressure and cardiovascular health. The regular consumption of black tea has been shown to lower blood pressure.

`With its flavonoids, black tea packs a powerful punch with many health benefits particularly for the heart and recent studies show the flavonoids work their magic whether or not we choose to add milk. Drinking four or more cups of black tea each day is quite simply very good for us.'


Is There Room at the Table For an Organic Food Eating Skeptic?

Keith Kloor still likes his organics even though he knows that they are not good for the environment

I'm your stereotypically disconnected urban food consumer who nonetheless cares about the environment and how my food is produced. That's why if you opened my refrigerator door, you would see organic milk, eggs, yogurt, cheese, salad greens, fruit, vegetables. I'm so brainwashed that I've even taken to buying organic bananas, because they look so fetchingly yellow. To be extra sure that we're not poisoning our kids with pesticide residue, my wife and I use all "all-natural, lemon scented" fruit and vegetable wash to detox our organic grapes and apples. (I know, what happened to good old fashioned tap water?) Even our frozen pizza is organic. (No GMOs, either, the package boasts.) On our bookshelves, you'd spot the works of Michael Pollan and Alice Waters, who teach us how to lead this virtuous, eco-conscious lifestyle.

Some readers are by now gasping at the hypocrisy of their hippy punching, sacred cow busting blogger, he who lambasts the nature-worshipping, organic-loving, GMO-fearing denizens of the world.

I got two words for you: Cognitive dissonance.

Actually, I'm well aware of the two parallel worlds I live in-the one at home, which is a temple to eco-wholesomeness, and the one in my head (translated to this blog and other places), where I question the assumptions of that other world.

Reconciling these two worlds is hard. It's kinda like a devout Catholic becoming an atheist while still identifying, culturally speaking, as a Catholic. How does one go about living a life that promotes earth-friendly organic tenets while in possession of the knowledge that organic farming, as I have learned, is not all it's cut out to be?

This is a dilemma I've been pondering of late, prompted in large part by arguments such as this one put forward by agricultural scientist Steve Savage:

"Contrary to widespread consumer belief, organic farming is not the best way to farm from an environmental point if view. The guiding principal of organic is to rely exclusively on natural inputs.  That was decided early in the 20th century, decades before before the scientific disciplines of toxicology, environmental studies and climate science emerged to inform our understanding of how farming practices impact the environment.  As both farming and science have progressed, there are now several cutting edge agricultural practices which are good for the environment, but difficult or impossible for organic farmers to implement within the constraints of their pre-scientific rules."

Savage is no organic basher. He's also a civil, mild-mannered communicator. In an interesting exchange with one of his readers in this other post (on pesticide use and GM crops) at his blog, he writes:

"I have great respect for organic farmers because of several that I have known for decades. I actually feel that the organic movement has been hijacked by an unholy alliance of marketers and anti-business activists and that its greatest insight and contribution (understanding the positive need to build soil quality) has been subjugated so that its "brand" is now defined almost entirely by what it is not: synthetics, GMO, irradiation."

This suggests that the organic movement was once a force for good, before ideological and commercial interests took it over. Is that true? More importantly, have the merits of organic farming been overstated? Is it okay to even raise these questions while snacking on my organic carrots?


1 comment:

Wireless.Phil said...

Tea killed one woman not that long ago.
However she used 100 tea bags in a pitcher.