The Truth about Caffeine

9 Caffeine Myths Explained

By Susan Kreimer, Special to LifeScript

Published April 17, 2009

Are you jonesing for coffee first thing in the a.m.? Need a Coke in the afternoon? Caffeine has a reputation of being bad for you. Is it a bum rap? Read on for the facts behind 9 common caffeine myths. Plus, test your caffeine IQ with our quiz…

Myth #1: Caffeine is addictive.
False: Although caffeine is considered a mild stimulant, it’s not addictive, according to the American Journal of Drug and Alcohol Abuse. Unlike classic stimulants – think cocaine and amphetamines – there’s rarely a strong compulsion to use caffeine.

But caffeine can be habit-forming. That’s why you may feel mild withdrawal symptoms if you skip your morning cup of joe or afternoon pick-me-up.

Typical symptoms include headache, restlessness and irritability. Should you decide to give up caffeine, don’t go cold turkey; instead, slowly decrease your caffeine consumption over a week.

Really though, why bother? Studies show moderate intake of caffeine actually enhances your mood and improves alertness. For adults, the American Dietetic Association suggests no more than 200 mg to 300 mg a day, which equals two to three cups of coffee.

Myth #2: Caffeine causes dehydration.
True: Caffeine is a mild diuretic, but “it’s not very pronounced,” says Franz H. Messerli, M.D., a professor of clinical medicine at Columbia University in New York City.

Still, diuretics make you have to pee. The more often you go, the more fluids you lose. And you’ll feel more dehydrated because you’re losing more fluids than you’re taking in.

“I wouldn’t drink a double espresso before a run, but would have no problem drinking a 12-ounce Coke,” Messerli explains. That’s because all fluids, even those with caffeine, contribute to the body’s daily fluid total.

Myth #3: Caffeine can make heart disease worse.
False: Doctors often tell cardiac patients, especially those with high blood pressure, to avoid caffeine. But there’s little proof that it raises the risk of heart attack, sudden death or abnormal heart rhythms.

In fact, coffee drinking may reduce risk of heart disease! A study by Autonomous University of Madrid of more than 126,000 people found that women who drank two to three cups of caffeinated coffee per day had a 25% lower risk of heart disease. Men didn’t show any higher or lower risk.

Drinking tea – black and green – may also have heart-healthy benefits.

"Tea in general seems to have cardiovascular benefits,” says Messerli, also a cardiologist and director of hypertension at St. Luke’s-Roosevelt Hospital Center in Manhattan. The “benefits of tea are probably due to its antioxidant properties,” he says.

But not all teas are created equal. Herbal ones such as chamomile, rosebud and elderberry don’t have the same antioxidants.

Plus, “when you add cream or milk, you may abolish the benefits,” Messerli says, “because it seems that the milk or the cream prevents the antioxidant substance from acting.”

Myth #4: Caffeine heightens hypertension risk.
True and false: Caffeine does cause a small, short-term boost in blood pressure, but it’s nothing serious, Messerli says, and has no lingering health effect.

In fact, a Harvard University Medical School study of 155,000 female nurses found no link between a decade of coffee drinking – with or without caffeine – and an increased risk of hypertension. Caffeinated colas did increase the risk, but that could be due to the sugar and other ingredients in sodas, not the caffeine. Tea drinking received mixed results.

As for men, a 33-year-long Johns Hopkins University study of more than 1,000 participants revealed that coffee played little role in hypertension risk.

Myth #5: Caffeine causes hyperactivity in children.
False: A kid on a Coke rush will practically bounce off walls. But studies show that a moderate amount of caffeine (40 mg to 200 mg) doesn’t make them hyperactive. (For reference, that 12-ounce can of Coke has 35 mg.)

Like adults, kids will get an energy boost from caffeine. But whether it’s soda, green tea or coffee, “on average, one serving a day wouldn’t be considered harmful overall for children,” says Suzanne Sheres, a pediatric clinical dietitian at Nemours Children’s Clinic in Orlando.

A bigger concern is the empty calories in soda and high-energy drinks favored by teens, she says.

In fact, small amounts of caffeine may help children diagnosed with attention-deficit hyperactivity disorder (ADHD). It can sharpen their focus and stimulate them to answer questions, Sheres says. So far, long-term studies haven’t shown whether it’s more beneficial to use caffeine than medication.

Myth #6: Caffeine causes bone loss.
True: Caffeine causes a slight, negligible increase in calcium excretion, according to a study by the Creighton University Osteoporosis Research Center in Omaha, Neb. And it would require about three cups of coffee for this to occur. Any calcium loss can be offset simply by consuming more calcium – a few tablespoons of milk, for example.

Even youngsters who drink one or two caffeinated beverages a day aren’t harming their bones, Sheres says, unless they consume them in place of milk.

Myth #7: Caffeine is linked to fibrocystic breast disease.
False: Caffeine intake isn’t related to the benign condition of lumpy breasts, reports the American Medical Association.

“There is no evidence to support the idea that caffeine causes fibrocystic changes,” says Katherine B. Lee, M.D., a staff physician in Cleveland Clinic’s Breast Center.

“It seems to contribute to breast pain, but does not cause breast cancer," Lee says. That’s because breast pain is hormonal, and caffeine causes blood vessels to dilate, adding to normal monthly breast tenderness.
"If a woman experiences breast pain, I inquire about caffeine and usually advise that she cut down on her intake,” she says.

Myth #8: Caffeine is unhealthy for pregnant women.
True: If you’re trying to conceive, you don’t have to give up the lattes. Research suggests that caffeine has little, if any, effect on the time it takes to conceive, and it’s not a risk factor for infertility.

But if you’re pregnant, you’ll have to watch how much you drink. Once a woman is carrying, the American College of Obstetricians and Gynecologists advises no more than one or two cups of coffee a day.
The National Institutes of Health recommends consuming no more than 300 mg a day during pregnancy, about three to four cups of regular coffee.

“The bottom line is, if the intake for a pregnant woman is less than 300 mg of caffeine a day, there should be no harm inflicted upon the baby,” says Linda Burke-Galloway, M.D., LifeScript Pregnancy Expert and a board-certified ob/gyn with the Florida Department of Health.

But too much caffeine may cause an irregular fetal heartbeat, which sometimes occurs in “women who eat excessive amounts of chocolate,” Burke-Galloway says.

Myth #9: Caffeine comes with calories galore.
False: On their own, coffee and tea have no calories or fat. It’s the flavored syrups, whole milk and cream that turn innocent caffeinated drinks into calorie bombs. Those tasty blended drinks can contain 200 to 600 calories.

And the creamers found in many offices? Two tablespoons can add 80 calories and four grams of fat. That equals a pat of butter.

To cut calories, choose the smallest size serving, either 8 or 12 ounces. Order your beverage with fat-free or skim milk and skip the syrup, whipped cream and sprinkles!

Drink
Caffeine

8-oz. brewed coffee
133 mg

8-oz. decaf coffee
5 mg

2-oz. Starbucks double espresso   
150 mg

12-oz. Diet Coke
47 mg

8.3-oz. Red Bull
80 mg

8-oz. hot cocoa
9 mg

12-oz. Jolt Cola
72 mg

8-oz. black tea
53 mg

Source: Center for Science in the Public Interest