10 Things You Need to Know About Caffeine

A handful of studies suggest that caffeine could potentially lower your risk forskin cancer。In an observational study (a study that shows an association but not causation) published in癌症Researchin July 2012, researchers using data from the Nurses' Health Study and the Health Professionals Follow-Up Study reported that the higher a person’s caffeine consumption, the lower their risk of developingbasal cell carcinoma。Similarly, in two 2015 studies, one published in February in theJournal of the National Cancer Institute另一个11月Epidemiology, researchers linked higher caffeine intake to a lower risk formelanoma, the deadliest form of skin cancer. But other factors besides caffeine could be at play, suggests theSkin Cancer Foundation。例如，有可能喝大量咖啡的人往往在室内工作，而不是少喝咖啡的人越来越少。

在英国考文垂大学的运动科学教授Michael Duncan表示，在您最喜欢的咖啡厅里有几个咖啡馆可以在您最喜欢的咖啡厅供电。在他进行的一个实验研究中，发表于The Journal of Nutrition, Health & Agingin December 2014, 19 healthy older adults between ages 61 and 79 who drank the equivalent of four cups of instant coffee or two cups of filtered coffee just before exercising were better able to invest effort in their workout than folks who didn’t get a caffeine boost. They also performed better at tasks like arm curls and a six-minute walk. Even their manual dexterity improved, notes Dr. Duncan.

There’s a reason you can buy over-the-counter pain relievers that combineibuprofen,acetaminophen, oraspirinwith caffeine:For some people, these combinations work better than the painkiller alone. Such products are often marketed as treatments for headaches ormenstrual cramps, but these aren’t the only types of pain that may be helped by a dose of caffeine.

In an analysis of four randomized, double-blind studies published in July 2015 in theCochrane Database of Systematic Reviews, researchers found that a single dose of 200 milligrams (mg) of ibuprofen plus 100 mg of caffeine was substantially more effective than a placebo at providing postoperative andmigrainepain relief over six hours.

While that particular drug combination is not commonly available in a commercial product, that dose — or a close approximation of it — can be achieved by taking 200 mg of ibuprofen along with a moderately strong cup of coffee.

在2015年7月发表的观察研究中，咖啡因消费与更好的内存和更好的高管（规划，组织和时间管理）（平均年龄74）有关Alzheimer’s & Dementia。The researchers, from the Brigham and Women’s Hospital in Boston, found that any amount of habitual coffee consumption was helpful.其他研究performed on mice have suggested caffeine might be helpful in treating Alzheimer’s disease.

研究表明，每天喝三到四杯含咖啡咖啡咖啡与发育中风的风险较低。coronary artery disease, saysSusanna C. Larsson, PhD, associate professor in the Institute of Environmental Medicine at the Karolinska Institute in Stockholm, Sweden. What’s more, according to her observational study published inBMC Medicine2015年9月，饮酒咖啡因咖啡似乎没有增加开发风险atrial fibrillation, the most common type of irregular heart rhythm. “Caffeine might be one of the components in coffee that reduces the中风的风险和coronary artery disease,” says Dr. Larsson.

“能量”射击式的饮料可以含有每杯咖啡因的500毫克咖啡因 - 咖啡因中的约5倍typical cup of brewed coffee,” says劳里赖特，博士, assistant professor of nutrition at the University of South Florida's College of Public Health and a spokesperson for theAcademy of Nutrition and Dietetics。“A healthy adult can safely consume two energy drinks a day, but I don’t recommend them for people 18 or under,” says Dr. Wright.

这不仅仅是咖啡因的咖啡因，使这些饮料可以享用糟糕的选择。“能量饮料，能量射击和苏打水被制造，以提供营养利益的少量能源，”Rania Batayneh，MPH，营养师和营养公司的所有者，营养咨询公司。

“Some energy drinks can contain as much as 70 grams of糖- 相当于17.5茶匙，“她说。

A study published in September 2015 inPloS Onerevealed that teens who downed five or more energy drinks in the past week were seven times more likely to have had a创伤性脑损伤（TBI）in the past year compared to teens who didn’t drink these “boosters.” Similarly, consuming energy drinks mixed with alcohol raised the likelihood of having had a TBI within the past year.

The study did not establish whether energy drink consumption predisposed teens to brain injuries or whether having a TBI somehow led teens to consume energy drinks — possibly as a coping mechanism.

Drinking energy drinks could interfere with a teen’s recovery from a TBI, says lead study authorMichael Cusimano, MD, a neurosurgeon at St. Michael’s Hospital and professor of neurosurgery at the University of Toronto in Canada. “Energy drinks contain high levels of caffeine and change the chemical state of the body, which can prevent people from getting back on track after a brain injury,” Dr. Cusimano notes.

Colon cancer patients who regularly drink caffeinated coffee may be lowering their risk of tumor recurrence and death from the disease, suggests a study published in November 2015 in the临床肿瘤学杂志。The observational study found that people with advanced (stage 3) colon cancer who drank four or more cups of caffeinated coffee a day had much lower odds of having a recurrence of the disease, or dying from it, by 52 percent compared with non-coffee drinkers. Even people who regularly drank just two or three cups a day seemed to reap some of the same benefits, although to a lesser degree.

Another observational study, published in癌症Epidemiology, Biomarkers & Preventionin April 2016, compared the coffee-drinking habits of more than 9,000 adults and found that “… drinking coffee is associated with lower risk ofcolorectal cancer, and the more coffee consumed, the lower the risk," according toStephen Gruber, MD, PhD, director of the University of Southern California Norris Comprehensive Cancer Center in Los Angeles and senior author of the study.

美国癌症协会的观察研究，于2013年1月发布American Journal of Epidemiology,found a strong relationship between caffeinated coffee intake and oral cancer death risk. Of the 968,432 men and women studied who were cancer-free at enrollment, 868 died due to oral cancer during the 26-year study period. Researchers found those who drank more than four cups of caffeinated coffee per day had about half the risk of death from oral cancers as those who only occasionally drank a cup. No association was found for tea drinking.

“Caffeine is a drug, and like any other drug, it can have harmful effects when ingested in high amounts,” Batayneh cautions. “At doses of more than 500 mg — about the amount in four cups of coffee — caffeine has been found to cause nervousness, irritability,insomnia,upset stomach, muscle tremors, andirregular heartbeat。“