By Amanda Gardner
That morning cup (or cups) of coffee may do more than just kick-start your day. Women who habitually drink several cups of coffee per day over the course of years or decades may be less likely than their peers to develop cancer in the lining of their uterus, a new study suggests.
Researchers at Harvard University analyzed data on 67,470 women between the ages of 34 and 59 who were followed for about 26 years. Compared to women who drank little or no coffee, those who averaged four or more cups per day had a 25 percent lower risk of developing endometrial cancer, and those who drank two or three cups per day had a 7 percent lower risk.
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Although the study, which was funded by the National Institutes of Health, doesn't prove that drinking coffee was directly responsible for reducing cancer risk, the researchers say a cause-and-effect relationship is plausible. Coffee drinking has been shown in previous studies to lower levels of insulin and estrogen, and chronically high levels of both hormones have been linked to endometrial cancer, the study notes.
The researchers urge coffee drinkers to hold the cream and sugar, however. Whatever benefits coffee may have on insulin levels would almost certainly be negated by the added calories and fat, which could contribute to insulin resistance and weight gain, they say.
Edward Giovannucci, MD, a professor of nutrition and epidemiology at the Harvard School of Public Health, in Boston, led the study. The findings, which were published today in the journal Cancer Epidemiology, Biomarkers & Prevention, add to a growing body of evidence that indicates coffee may offer more benefits than harm when it comes to health -- and not just cancer health.
In recent years, studies have linked coffee consumption to a lower risk of liver cancer and lethal prostate cancer, as well as a lower risk of depression, type 2 diabetes, Parkinson's disease (mainly in men), and cirrhosis of the liver. Research in mice even suggests that coffee may help protect against the brain changes associated with Alzheimer's disease.
It's not entirely clear how drinking coffee might improve health, but caffeine seems to be only part of the picture, since studies on decaffeinated coffee have turned up apparent health benefits as well. (In the new study, decaffeinated coffee appeared to lower the risk of endometrial cancer, but the researchers had too little data on decaf-only drinkers to reach any reliable conclusions.)
Compounds with antioxidant properties -- such as chlorogenic acid -- likely play a role as well. "There are estimated to be over a couple thousand different components in coffee, many of which are antioxidants," says Donald Hensrud, M.D., chair of preventive medicine at the Mayo Clinic, in Rochester, Minn.
Coffee contains even more antioxidants than green tea, says Hensrud, who was not involved in the new research. Giovannucci and his colleagues looked at tea drinkers in their study as well, but they found no relationship between tea consumption and endometrial-cancer risk.
The study has several key shortcomings that mean the findings should be interpreted with caution. The researchers relied on biennial diet questionnaires to assess coffee and tea intake, for instance, and although they controlled for a wide range of health factors and behaviors, they can't rule out the possibility that heavy coffee drinkers are socially or culturally different from their peers in ways that could affect cancer risk.
Leo B. Twiggs, M.D., a professor of obstetrics and gynecology at the University of Miami Miller School of Medicine, says a "whole host of reasons" other than coffee consumption could potentially explain the study findings.
Women concerned about cancer risk shouldn't necessarily increase their coffee intake, in other words. "It's OK to drink coffee as long as you don't drink lots of it," Twiggs says.
Although drinking a lot of caffeinated coffee doesn't appear to have any serious health consequences (such as raising the risk of high blood pressure, or hypertension), Hensrud says, it can carry some potential side effects, including insomnia, worsened heartburn, heart palpitations, anxiety, and irritability.
The "take-home message" of the new study should not be to "go out and drink more than four cups a day," says Steven R. Goldstein, M.D., a professor of obstetrics and gynecology at New York University Langone Medical Center, in New York City.
The most effective way for women to detect -- if not prevent -- endometrial cancer is to look out for irregular menstrual bleeding and consult a doctor if they notice anything unusual, Goldstein says.
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Coffee (Or At Least, The Caffeine!) Can Help You Proofread Better
The caffeine in coffee could actually help you to <a href="http://psycnet.apa.org/psycinfo/2011-23154-001/" target="_hplink">spot grammar errors</a>, according to a new study in the <em>Journal of Experimental Psychology</em>.
Researchers found that <a href="http://bodyodd.msnbc.msn.com/_news/2011/10/26/8498728-tank-up-on-java-unleash-your-inner-editor-says-study?ocid=twitter" target="_hplink">caffeine helped students to correct errors</a> in subject-verb agreement and verb tense, MSNBC reported. However, the caffeine still didn't seem to make a difference at identifying misspelled words -- sorry.
Coffee Could Lower Women's Depression Risk
Women who drink a few cups of <a href="http://www.huffingtonpost.com/2011/09/27/coffee-cuts-depression-women_n_982122.html" target="_hplink">caffeinated coffee have a lower risk of depression</a> than women who don't drink any coffee, according to a Harvard study.
That research, published in the <em>Archives of Internal Medicine</em>, shows that women who drink two to three cups of coffee a day have a 15 percent lower risk, while women who drink four or more cups of coffee a day have a 20 percent lower risk.
Study research Dr. Albert Ascherio <a href="http://www.huffingtonpost.com/2011/09/27/coffee-cuts-depression-women_n_982122.html" target="_hplink">told HuffPost</a> earlier that "caffeine is known to affect the brain," because it "modulates the release of mood transmitters."
"I'm not saying we're on the path to discovering a new way to prevent depression," he said. "But I think you can be reassured that if you are drinking coffee, it is coming out as a positive thing."
Coffee Could Save Your Brain
... Well, maybe. A study in the <em>Journal of Alzheimer's Disease</em> suggests that there's something in coffee -- though researchers have yet to determine what exactly that "something" is -- interacts with caffeine to boost the levels of granulocyte colony stimulating factor (GCSF), a growth factor that seems to be able to <a href="http://www.huffingtonpost.com/2011/06/24/coffee-could-ward-alzheimers_n_882931.html" target="_hplink">fight off Alzheimer's disease in mice</a>.
The amount of coffee needed in the study is equivalent to about four or five cups of coffee for humans.
Researchers said <a href="http://www.j-alz.com/press/2011/20110621.html" target="_hplink">GCSF likely has this effect</a> because it causes stem cells in the bone marrow to come into the brain and remove the beta-amyloid plaques associated with Alzheimer's disease. It also has a role in forming brain cell connections and creating new brain neurons, researchers said.
Coffee Could Lower Men's Prostate Cancer Risk
A Harvard School of Public Health study shows that men who drink six cups of coffee a day have a 60 percent decreased <a href="http://www.huffingtonpost.com/2011/05/18/coffee-can-cut-prostate-c_n_863472.html" target="_hplink">chance of developing a dangerous form of prostate cancer</a>, as well as a 20 percent decreased chance of developing any other kinds of prostate cancer.
The study, published in the <em>Journal of the National Cancer Institute</em>, also shows that just <a href="http://jnci.oxfordjournals.org/content/early/2011/05/17/jnci.djr151.abstract" target="_hplink">drinking just some coffee a day</a> -- just one to three cups -- could still cut prostate cancer risk by 30 percent.
Coffee Could Ward Off The World's Most Common Cancer
New research presented at the American Association for Cancer Research conference shows that coffee could help to <a href="http://www.huffingtonpost.com/2011/10/24/coffee-most-common-cancer_n_1025089.html" target="_hplink">ward off basal cell carcinoma</a>, the most common cancer in the world.
Researchers from Brigham and Women's Hospital and Harvard Medical School found that women who drink three or more cups of caffeinated coffee a day have a 20 percent lower risk of the skin cancer, while men had a 9 percent lower risk.
Decaf coffee didn't seem to have the same protective effect -- so "our study shows that the inverse association with BCC appears due to caffeine, not other components in the coffee consumption," study researcher Fengju Song, Ph.D., earlier <a href="http://www.huffingtonpost.com/2011/10/24/coffee-most-common-cancer_n_1025089.html" target="_hplink">told HuffPost</a>.
Coffee Could Protect You From Type 2 Diabetes
Drinking coffee is associated with a <a href="http://archinte.ama-assn.org/cgi/content/abstract/169/22/2053" target="_hplink">lower Type 2 diabetes risk</a>, with more coffee consumption linked to a greater decrease in risk, according to an <em>Archives of Internal Medicine</em> review of studies from 2009.
In that review, researchers looked at data from more than 450,000 people in 18 studies, and found that for every extra cup of coffee drank a day, a person's risk of Type 2 diabetes decreased by 7 percent.
However, researchers cautioned that "the putative <a href="http://archinte.ama-assn.org/cgi/content/abstract/169/22/2053" target="_hplink">protective effects of these beverages</a> warrant further investigation in randomized trials."
Coffee Could Decrease Parkinson's Risk
Drinking <a href="http://www.ncbi.nlm.nih.gov/pubmed/20182023" target="_hplink">a few cups of coffee a day</a> could lower the risk of developing Parkinson's disease by as much as 25 percent, according to a study published last year in the <em>Journal of Alzheimer's Disease</em>.
In that review of studies, which was published in the <em>Journal of Alzheimer's Disease</em>, researchers examined 26 studies that involved 125,000 British people, to find that <a href="http://www.telegraph.co.uk/health/healthnews/7815087/Coffee-can-cut-chances-of-developing-Parkinsons-disease-according-to-new-research.html" target="_hplink">two or three cups of coffee</a> seemed to have the optimal effect, <em>The Telegraph</em> reported.
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Posted: 11/23/11 11:56 AM ET