Coffee. Just how much can your body take?

Coffee. Just how much can your body take?. About £850million is spent on coffee every year. It is addictive and people often consume it to keep alert or even lose weight. But last week's report that you are more likely to suffer rheumatoid arthritis if you drink large amounts is one more blow for one of our favourite drinks.

So just how much coffee is good and bad for you? PETA BEE reports . . .

ONE CUP PROS:

It increases alertness and short-term memory, and even alters your mood. The caffeine in a cup of coffee stimulates the central system as it simultaneously lowers blood sugar and increases the brain's demand for sugar. The result is a temporary 'lift'.

A study of 600 people asked to record their breakfast habits by University of Bristol researchers found that those who had a cup of regular coffee performed better and were more upbeat than those who drank decaffeinated coffee or nothing.

CONS:

A cup taken one hour before bed can be enough to trigger insomnia, so avoid it altogether if you have trouble dropping off.

Drinking coffee with meals is known to inhibit the absorption of iron and calcium from food, putting women at greater risk of anaemia and osteoporosis.

Caffeine also has a diuretic effect and just one cup before exercise will trigger unwanted fluid loss.

TWO CUPS

PROS:

Research in the Journal Of Sports Medicine showed how two cups taken two hours before exercise enhanced the performance of athletes in marathon running.

And, although coffee was linked to the increased risk of miscarriage in the Eighties, a major study last year showed pregnant women who consumed around two cups a day suffered no side-effects. CONS:

Dr David Kerr, of the Royal Bournemouth Hospital, has been looking at the effects of coffee on mental alertness and disputes some of the more positive findings. 'Within half an hour of drinking one or two cups, the flow of blood to the brain is reduced by 10-20pc,' he says. 'Combine that with low blood sugar, either in diabetics or those who haven't eaten for a while, and you can soon start to have palpitations, feelings of anxiety or blurred vision.'

THREE CUPS PROS:

A study published last year in the Journal Of The American Medical Association reported that men who drink two to three cups of coffee a day had a 40 pc lower risk of developing gallstones than non-coffee drinkers.

Only caffeinated coffee, not decaf, seemed to have the effect of stimulating contractions in the gall bladder and lowering cholesterol in bile that can form gallstones. Up to three cups a day can boost aspirin's painkilling effects.

CONS:

Withdrawal symptoms can occur after regular consumption of just two-and-a-half to three cups a day. Caffeinism, as it is sometimes called, shows as headaches, migraine and sickness.

FOUR CUPS PROS:

Researchers at the University of Bristol showed that drinking four cups each morning helped people to work more efficiently. Morning coffee, in particular, can enhanced alertness. Some people think caffeine boosts the metabolism by stimulating the release of fats into the blood which are then burned for energy, but evidence for its weight-loss benefits is not conclusive.

CONS:

Drinking four or more cups a day may increase susceptibility to rheumatoid arthritis. Scientists found a strong link between coffee and a biochemical marker for the disease and showed how people who drink this much are twice as likely to test positive for arthritis.

If you already lead a stressful lifestyle, your coffee habit could make things worse. At Duke University in the U.S. it was discovered that people who drink four cups in the morning had slightly elevated blood pressure levels and greater amounts of stress hormones during the day.

FIVE CUPS PROS:

Professor Edward Giovannucci of Harvard University Medical School spent a year reviewing the health benefits of coffee and concluded that the risk of colorectal cancer drops 24 pc among those who drink more than four cups a day.

CONS:

Several studies have shown that the consumption of five or more cups a day is a risk factor for osteoporosis since a heavy caffeine intake may interfere with calcium absorption.

However, the same findings have often proved the negative effects of calcium loss can be offset by adding a tablespoon of milk to your cuppa. The National Osteoporosis Society says there is no conclusive evidence that coffee thins bones, but advises no more than five cups to be safe.

SIX CUPS OR MORE

PROS:

Up to six cups a day may help to protect against Parkinson's Disease. Earlier this year it was shown how men who didn't drink any coffee were five times more likely to develop Parkinson's than those who drank the most. It is thought that heavy coffee drinkers may have a brain composition that makes them resistant to the disease.

CONS:

Six or more cups a day can double the risk of a miscarriage, according to researchers at the University of Utah, who measured the blood levels of paraxanthine, the substance produced when the liver breaks down caffeine, in pregnant women.

More than six cups a day could increase the risk of acid reflux and ulcers. It is unknown whether the caffeine or another substance causes the adverse effects.

Meanwhile, a New Zealand study showed that more than six cups a day drunk by pregnant mothers increases the risk of cot death.

And drinking 11 cups a day leaves a person 15 times more likely to get rheumatoid arthritis than non-drinkers, according to the National Institute of Public Health in Finland.

Five times that amount and you risk caffeine intoxication, a recognised medical condition according to the American Psychiatric Association. ( dailymail.co.uk )