Milk dilutes the benefit of black tea

[Guest guest]

Folks,

The article below discusses the effect of milk on tea with respect to

heart disease, but mentions that studies will now focus on the effect

of milk on the cancer-preventive effect of tea.

http://eurheartj.oxfordjournals.org/cgi/content/abstract/ehl442v1

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Drinking tea can reduce the risk of heart disease and stroke but only

if milk is not added to the brew, German scientists said Tuesday.

Research has shown that tea improves blood flow and the ability of the

arteries to relax but researchers at the Charite Hospital at the

University of Berlin, Germany, found milk eliminates the protective

effect against cardiovascular disease.

" The beneficial effects of drinking black tea are completely prevented

by the addition of milk, said Dr. Verena Stangl, a cardiologist at the

hospital.

" If you want to drink tea to have the beneficial health effects you

have to drink it without milk. That is clearly shown by our

experiments, " she told Reuters.

Tea is second only to water in worldwide consumption so any benefits

could have important public health implications. But until now it was

not known whether adding milk had an impact.

Stangl and her team discovered that proteins called caseins in milk

decrease the amount of compounds in tea known as catechins which

increase its protection against heart disease.

They believe their findings, which are reported in the European Heart

Journal, could explain why countries such as Britain, where tea is

regularly consumed with milk, have not shown a decreased risk of heart

disease and stroke from drinking tea.

The researchers compared the health effects of drinking boiled water

and tea with and without milk on 16 healthy women. Using ultrasound,

they measured the function of an artery in the forearm before and two

hours after drinking tea.

Black tea significantly improved blood flow compared to drinking water

but adding milk blunted the effect of the tea.

" We found that, whereas drinking tea significantly increased the

ability of the artery to relax and expand to accommodate increased

blood flow compared with drinking water, the addition of milk

completely prevents the biological effect, " said Dr. Lorenz, a

molecular biologist and co-author of the study.

Tests on rats produced similar results. When rodents were exposed to

black tea they produced more nitric oxide which promotes dilation of

blood vessels. But adding milk blocked the effect.

Tea has also been shown to have a protective effect against cancer so

the findings could have further implications.

" Since milk appears to modify the biological activities of tea

ingredients, it is likely that the anti-tumor effects of tea could be

affected as well, " said Stangl.

" I think it is essential that we re-examine the association between

tea consumption and cancer protection, to see if that is the case, "

she added.

http://snipurl.com/plaintea

-Diane