Coffee, much debated and discussed for its impact on health, has been researched extensively. The most widely consumed beverage around the world, is known for the stimulation it brings, thanks to the high caffeine content. Recent evidence suggests an inverse association between coffee consumption and risk of a host of chronic lifestyle diseases. That means, the more coffee you drink, the lesser are your chances of getting type 2 diabetes, Parkinson’s and alcohol related liver disease.
What nutrients does coffee have?
A number of components are found in coffee, which have a potential impact on human health. Antioxidants, magnesium, potassium and niacin are some of them. Caffeine is the major active ingredient. Other sources of caffeine in the diet are chocolate, tea, soft drinks. Caffeine acts as a stimulant to the central nervous system, leading to increased activity of dopamine and consequently, increased alertness and reduced physical fatigue. Caffeine is rapidly absorbed from the intestine and the effects are felt within 90 minutes of consumption. However, excessive caffeine consumption, more than 250 mg at one time (approximately two to three cups of brewed coffee) leads to adverse effects that include palpitation, anxiety, agitation and gastrointestinal distress. When you suddenly stop drinking coffee overnight, you could experience withdrawal symptoms that include headaches, drowsiness, depression and irritability.
Health benefits
The most significant health benefit of coffee stems from multiple prospective epidemiological studies demonstrating long term coffee consumption is associated with decreased risk of type 2 diabetes irrespective of sex, obesity or geographic location. The study compared those who drank six to seven cups of coffee per day to those who drank four to six cups and zero or two cups, and the first group had the least risk of developing diabetes.
The antioxidant properties of coffee are due to chlorogenic acid which increases insulin activity and sensitivity. More studies are needed to understand how this substance helps in glucose control. Ross et al. Examined data on more than 8000 Japanese American men who were followed up to 30 years and found that those who abstained from coffee had five fold risk of Parkinson’s as compared to coffee drinkers. At the tenth year of follow up in this study, there was a 76 % lower risk of liver cancer as well in coffee drinkers.
Some studies have shown a reduced risk of gallbladder disease and gout (a condition resulting from high levels of uric acid in blood) with coffee consumption, although more confirmatory studies are needed. Many large scale studies have demonstrated coffee’s ability to prevent liver disease and a reduced risk of colorectal cancer.
The bottomline, moderate consumption of coffee has been shown to be safe, and confers health benefits. But excessive consumption has adverse effects, including reduced absorption of other nutrients such as iron, calcium and zinc. Pregnant women and those with heart disease are advised to limit consumption of coffee to not more than two cups a day.