New results from a large study did show a 25 percent lower risk of gallstones among women who regularly drink four or more cups of coffee a day (compared to women who drink none). This finding, published in the December 2002 issue of the journal Gastroenterology, comes from the famous Harvard Nurses' Health Study, which has followed more than 80,000 women for 20 years. An earlier study found that drinking coffee lowers gallstone risk among men.
The Harvard researchers suggested that the caffeine in coffee is responsible for the gallstone effect, perhaps because it triggers gallbladder contractions that may discourage stone formation.
Maybe so, but if you're prone to gallstones (risks are highest among overweight, mid-life women, diabetics and those whose mothers had gallstones), you can take a number of other preventive measures that may be better for overall health:
- If appropriate, lose weight slowly (crash dieting can lead to gallstone formation).
- Drink six to eight glasses of water a day to keep the bile in your gallbladder fluid and help you digest and absorb fat (most gallstones are composed of cholesterol).
- Make sure you get 1,000 to 1,200 mg of calcium from all sources daily (associated with a lower incidence of gallstones). Men should get 500 to 600 mg from all sources.
- Take 300 mg of curcumin (an active component of the yellow spice turmeric) three times a day to increase the solubility of your bile. Choose a standardized product.
- Take 200 mg of supplemental vitamin C daily (one study found that women with higher blood levels of vitamin C were half as likely to develop gallstones as those with lower levels).
As for the coffee connection, I recommend that you continue to cut back. While coffee may prevent gallstone formation, it is also an addictive drug that can cause or worsen other troublesome health problems: headaches, anxiety, insomnia, cardiac arrhythmia (palpitations), high blood pressure, gastrointestinal and urinary disorders, prostate trouble and PMS. If you are interested in the positive effect of caffeine on gallstones, I suggest drinking green tea, which has less caffeine than coffee and a host of health advantages including protection from cancer.
Andrew Weil, M.D.