For most people, a morning cup of java isn’t harmful. But if you rely on coffee to get you out of bed, to stave off midmorning headaches and to avoid the 3 p.m. crash, you may be hooked on one of the most popular drugs in the world.

Nearly 90 percent of American adults drink coffee on a regular basis. More than 50 percent of adults, meanwhile, consume just over three cups of coffee a day.

But caffeine is a tricky stimulant to shake. Though tolerance levels vary, drinking just 100 milligrams per day — the amount of a small cup of brewed coffee — and then giving it up can lead to withdrawal symptoms ranging from headaches and depression to flulike nausea and muscle pain, according to the National Institutes of Health.

Caffeine may have some health benefits, but so far research is weak. Some kinds of headaches cause blood vessels to widen; caffeine temporarily causes them to narrow. Coffee may also help reduce your risk of Parkinson’s disease.

But coffee — like sugary breakfast foods — can create a cycle of extreme energy swings. The National Institutes of Health also reports that caffeine raises blood pressure and increases feelings of stress, anxiety and road rage. It can leave you feeling wired 12 to 16 hours after the last cup, wreaking havoc on sleep. And it can exacerbate health conditions such as diabetes by making blood sugar rise faster than usual.

To start weaning yourself off the joe, figure out how much caffeine you’re ingesting during the day, including soft drinks and energy drinks; if you can’t track it, it’s too much. Also try the following tips:

Wake up and drink 8 ounces of water. This strategy seems to slow coffee consumption and also works if you have a morning diet or regular soda habit, said Brian Wansink, founder and director of the Cornell University Food and Brand Lab and an expert on psychology and food consumption.

Choose your approach. Some people can go cold turkey; others need to gradually reduce. "There’s no evidence that either approach is superior," said James Lane, a caffeine researcher and professor in the department of psychiatry and behavioral sciences at Duke University Medical Center. If you’re a heavy coffee drinker — eight cups a day — gradual withdrawal can help prevent the dreaded headaches and fogginess. If you drink two cups, you may be able to bite the bullet. "Withdrawal symptoms most likely disappear in two or three days," said Lane.

Taper: To minimize withdrawal symptoms, gradually reduce the amount of caffeine by drinking half regular and half decaffeinated and gradually increasing the amount of decaf, said Ling Wong, a Santa Monica, Calif.-based nutrition and wellness coach. "You can also try tea — black or yerba mate — which has the richness of coffee without that much caffeine," Wong said. "Rooibos is an herbal tea that has a rich body similar to black tea, without any caffeine. Green tea and white tea are also great choices," she said.

Try Sanka. After several unsuccessful attempts, Barry Maher said he managed to quit drinking several quarts of coffee a day by substituting "the worst-tasting coffee substitute that ever existed, Sanka. Nothing could have made me develop an aversion to coffee quicker than associating it with a vile brew like that," said Maher, a professional speaker in Corona, Calif.

Fruit juices might seem like a healthy option to coffee, but it’s better to avoid all sugar-sweetened beverages, whether it’s added or high natural sugar. "The stomach doesn’t feel full so the brain can’t know it, and you keep eating," said physician and chef John LaPuma. "Because they boost glycemic load, they inflame arteries, disable insulin and clog up the beta-cells in the pancreas, where insulin is made. They can also make the liver store fat. Not a pretty picture." A better alternative? Sparkling water.