Sunday July 19, 2009

Better latte than never

By LEE TSE LING

Coffee is good for you. Coffee is bad for you. Coffee does no good. Coffee does no harm. What is one to believe?

OPINION has been divided on the health impact of coffee, because opinion has tended to sway with the publication of each new scientific study. That’s what’s called reportage.

However, after several decades of studies, it seems the cumulative evidence is in favour of the dark brew so many hold dear – fabulous news, if you’re a coffee lover like me (it’s the sun of my mornings and my light in the night). But before anyone starts prescribing daily kopi doses, let’s see exactly what the experts and science say today.

Coffee is safe

Coffee consumption has been linked to various health scares over the years, including increased heart attack risk, blood pressure, and cholesterol levels; addiction issues and sleep disruption; cancers of the digestive tract and bladder; and miscarriage and abnormal foetal development. However, given its widespread consumption and the scale of its trade, coffee research has also been well-funded and documented.

“From the literature, we see coffee has been the best investigated food item in terms of safety in daily consumption,” says Nestle innovation acceleration manager for coffee and beverages Dr Elke Gerhard Rieben. “Decades of evidence say moderate coffee consumption (three to five cups a day) is scientifically proven as safe for the general healthy population. So you can really enjoy your cup of coffee without further concern.”

The caffeine in coffee keeps you awake longer.Can the antioxidants in it help you live longer too.- Reuters

Coffee slows ageing

Coffee isn’t just safe to drink, it’s also good for you. Or rather, the antioxidants in it are good for you, and instant coffee has been shown to have up to twice as much antioxidant activity as cocoa and green tea (Richelle, M. et al, Journal of Agricultural and Food Chemistry 2001).

The main antioxidants in coffee are called chlorogenic acids, which are polyphenols – one of many different groups of plant-derived antioxidants recognised today. Antioxidants are compounds that can prevent or repair free radical damage (“oxidative stress”, hence “antioxidants”) in the body, and so slow down the degenerative aspects of cellular ageing. They can also reduce chronic inflammation, and so reduce the risk of developing certain chronic diseases.

Antioxidants may be just the tip of the coffee iceberg. While it is well established that caffeine in coffee improves alertness, mental performance, and physical performance, coffee is a complex brew that contains many other less studied and potentially beneficial biologically active compounds.

Some of the areas on which research is now focused include investigating the effect of coffee consumption on slowing down age-related cognitive decline, and lowering the risk of developing type 2 diabetes, and Alzheimer’s and Parkinson’s disease.

Prof Gary Williamson... Coffee makes a considerable contribution to the total antioxidant consumption in a coffee drinker's diet.

Drinking coffee is just one enjoyable way to boost your daily antioxidant intake. Eating fruits and veggies, drinking tea, and even having some chocolate are others, and drinking coffee alone shouldn’t be considered a comparable substitute for a varied and well balanced diet.

Too much of a good thing

Strong, weak, brewed, instant, decaff – what affects the antioxidant content of your daily cup?

>Stronger coffee (extra “kau”) contains more antioxidants per unit volume compared to weaker coffee. But strong coffee tends to be drunk in smaller volumes than weak coffee, so often the antioxidant dose evens out in the end.

>Decaffeination removes caffeine (and according to some connoisseurs, taste), but is supposed to leave the antioxidants intact.

>Brewing under high pressure, espresso-style, was demonstrated by a Spanish study to extract more antioxidants than filter and plunger/press methods (Lopez-Galilea, I. Journal of Food Chemistry 2004).

>The same study also showed that roasting coffee with some sugar – a common practice with Malaysian coffee roasters - produces beans with higher antioxidant contents.

>The Richelle study also showed green Robusta coffee beans had twice as much antioxidant activity as green Arabica beans, but no difference was found between the two after roasting.

Since drinkers enjoy their coffee in a variety of ways from different beans, producers, and brewers, at home and away, the only principle you can apply here is volume: the more you drink, the more antioxidants you get. And you literally can’t get too much of a good thing, assures functional foods expert Prof Gary Williamson from the University of Leeds, UK.

“For something like chlorogenic acid, it’s almost impossible to get a lethal dose,” he says. “It’s only at very, very high levels that it’s possible to get any toxicity. To reach those in humans, you’re talking about hundreds of cups of coffee a day. Antioxidants are not something you need to worry about if you have excessive coffee consumption – you’d be worried about too much caffeine first.

(Excessive caffeine can lead to a fast heart rate, excessive urination, nausea, vomiting, anxiety, tremors, and – obviously – difficulty sleeping.)

Dr Elke Gerhard Rieben . . . Decades of evidence say moderate coffee consumption is safe for the general healthy population.

“If, however, you concentrate these antioxidants into a pill, then it’s always possible for people to think ‘if one pill’s good for me, 10 must be even better’. That is a situation where you can get an excessive dose, but I don’t believe it’s possible from normal food and drink consumption.”

As for an optimal intake value, nobody is recommending one yet. However, a wholesome five-a-day diet (one that incorporates five portions of fruits and vegetables weighing about 80g each a day, as recommended by the UK National Health Service) will give you 1000mg of polyphenols. As one cup of coffee will give you a about tenth of that, coffee can certainly be considered a good source of these age-defying nutrients.

Too much of a bad thing

One thing you can get too much of in coffee, besides caffeine, is sugar.

“If your morning cup of coffee is your only source of sugar, then probably it’s okay,” concedes Dr Rieben, “But if you combine it on many other occasions of consuming coffee, then it might be a problem. Our recommendation is to avoid adding sugar to every cup of coffee. If you are really an intense sugar-lover, you may consider using a sweetener.”

Prof Williamson begs to differ: “If adding a bit of something you like to a healthy product means you eat or drink more of it, go ahead. Many people don’t like plain salad for example. A lot of people then add salad dressing, which is high in calories and fat. But you don’t actually add very much to a salad, and if it makes you enjoy the salad, which is very good for you, then that’s a good thing.

“So if adding one or two spoonfuls of sugar to the coffee is what you like, then just do it. It doesn’t matter, because all you have to do is have one can of carbonated drink, and you’d have as much sugar in that as you would in 10 cups of coffee. For me, it’s not something you should worry about. I don’t believe even if you have five cups of coffee with a spoonful of sugar, it’s going to make you particularly obese.”

The bean goes beyond

If the coffee bean is so good for us, and even better for business, what about the rest of the tree? The answer is coming soon, as the coffee industry is actively exploring alternative products like whole coffee fruit (or “cherry”) extracts, coffee tree leaf infusions (enjoyed like tea leaves), and green (unroasted) coffee.

Of the three, green coffee is the furthest along in terms of development. According to Dr Rieben, it has a light, refreshing taste that goes in the direction of tea, with more of a bean taste and less of a green leaf taste. It also packs a more powerful polyphenol punch than roasted coffee.

The green bean brew is good news for non-coffee drinkers, who will surely appreciate this appealing antioxidant-rich alternative. As for hardcore coffee addicts, I’m guessing we’ll be sticking to the full and heady perfumed high we’ve come to love and depend on.