Is coffee a "health food" now?

Health Benefits of Coffee - MarketWatch video.

Coffee is not usually thought of as health food, but some recent studies suggest that it can be beneficial.

A 2005 JAMA meta-analysis concluded that habitual coffee consumption was consistently associated with a lower risk of Type 2 diabetes. However, caffeine, seems to have little to do with it. In fact, caffeine (C8H10N4O2) is the natural pesticide of coffee beans, paralyzing and killing insects that try to feed on them.

A Norwegian study found that women who drank 1-3 cups a day reduced their risk of cardiovascular disease by 24% compared with those drinking no coffee at all.

Antioxidants in coffee may decrease inflammation, reducing the risk of disorders related to it, like cardiovascular disease. A typical serving of coffee contains more antioxidants than typical servings of grape juice, blueberries, raspberries and oranges.

References:
Health Benefits of Coffee - WebMD.
Coffee as a Health Drink? Studies Find Some Benefits - New York Times, 2006.

Caffeine (C8H10N4O2) is the natural pesticide of coffee beans, paralyzing and killing insects that try to feed on them

Coffee vs. Tea - Infographic of Health Benefits and Risks http://goo.gl/StIsr

Caffeine is a major source of antioxidant activity in coffee. WebMD, 2011.

Eyes Can Absorb Antioxidants From Green Tea, Which May Have a Protective Effect (In Rats)

Researchers fed laboratory rats green tea extract and then analyzed their eye tissues.

The results showed that different parts of the eye absorbed varying amounts of catechins. The area with the highest concentration of catechins was the retina, which is the light-sensing tissue that lines the back of the eye.

Antioxidant activity lasted for up to 20 hours after drinking green tea extract.

This is an animal study and we have no evidence that the same effect takes place in humans.

References:
http://www.webmd.com/eye-health/news/20100218/green-tea-good-for-the-eyes

Coffee vs. Tea - Infographic of Health Benefits and Risks http://goo.gl/StIsr
Image source: Green Tea leaves in a Chinese gaiwan. Wikipedia, Wikimol, Creative Commons Attribution ShareAlike 2.5 License.

Hot vs. cold water steeping of tea: No difference in antioxidant activity

A new popular way of making tea is to steep leaves in cold water.

The study authors investigated whether antioxidant activity of teas is affected by hot or cold water steeping and if this correlates with their polyphenol content and metal-chelating activity.

A set of five loose tea samples, consisting of unblended and blended teas, was analysed following infusion in either hot water (90 °C, 7 min) or cold water (room temperature, 2 h).

Antioxidant activity, measured as hydrogen-donating ability, showed no significant differences among hot or cold teas, except in the case of white tea, where higher values were obtained after cold water steeping.

The antioxidant activity of the teas correlates with their phenolic content and metal-chelating activity. Cold teas were better inhibitors of in vitro LDL conjugated diene formation.

The authors concluded that the potential health benefits of tea may be maximised by methods of preparation.

According to BMJ, drinking hot tea may cause cancer:



References:
Hot vs. cold water steeping of different teas: Do they affect antioxidant activity? Elisabetta Vendittia, Tiziana Bacchettia, Luca Tianoa, Patricia Carlonib, Lucedio Grecib and Elisabetta Damiania. Food Chemistry, Volume 119, Issue 4, 15 April 2010, Pages 1597-1604.

BMJ Video: Drinking hot tea may cause cancer

Coffee vs. Tea - Infographic of Health Benefits and Risks http://goo.gl/StIsr
Image source: Green Tea leaves in a Chinese gaiwan. Wikipedia, Wikimol, Creative Commons Attribution ShareAlike 2.5 License.