The way you prefer your coffee can vary as much as its effects on you versus another. You may consume several cups of coffee in a day and still sleep soundly, while your coworker or significant other gets jittery after only one cup. For some people, caffeine is completely off limits. The question, of course, is why?

Caffeine is the most widely used mood-altering drugs in the world, according to Johns Hopkins School Medicine. It’s part of a group of compounds that stimulate the nervous system and is felt throughout the body. Depending upon how much caffeine you drink determines how fast your heart beats and how well your metabolism works.

Even if you don’t drink coffee, most of us get caffeine in some form such as hot or iced tea, soda, and chocolate. Yet, the levels of caffeine in coffee and even tea are higher which means the effects are bigger, too.

How much caffeine is too much? Physically the body responds to caffeine as soon as it goes in it. Blood vessels constrict and expand, while stomach acids and urine output increase. For a while, you may feel more alert. Depending on your sensitivity to caffeine, how much your drink, your body weight and physical condition, caffeine can cause any of the following symptoms:

  • Headaches
  • Trembling
  • Disorientation
  • Insomnia
  • Irritability

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So, what’s the scoop then on why one person may feel badly on caffeine while another person appears fine? Basically, it comes down to your body and lifestyle choices. The top seven reasons you or someone you know may be sensitive to caffeine include:
You don’t drink that much of it. Basically if you’re not used to something, your tolerance for it will not be strong. No matter how robust the beverage! Studies suggest that drinking more caffeine lowers the creation of a hormone that makes you happier, so your body craves the caffeine to keep you feeling good. This is why some people say they are addicted.

  1. Your genetics program your response. Caffeine binds or “sticks” to a receptor in the brain. The intensity of the caffeine’s effect depends on the person’s brain receptors and how well it binds to caffeine. If it does this easily, a person will feel jittery.
  2. Your metabolism is slow. There is an enzyme in the liver that determines how coffee is metabolized and varies from person to person. Anyone with less of the enzyme will take longer to get rid of the caffeine, so the side effects last longer. The digestive system also can be aggravated by coffee since it activates the nerve in the stomach that dumps substances into the intestine. Did you ever notice you may need to use the bathroom quickly after drinking coffee? It’s not called the “dumping effect” for no reason.
  3. Your medicine cabinet holds the answers. Certain antibiotics, asthma drugs, and Echinacea, a popular herb used to shorten the length of a cold or flu, can interfere with caffeine and keep it in the bloodstream for a longer amount of time.
  4. You suffer from anxiety disorder. Already jittery? Coffee likely will make you feel more so. Caffeine irritates and intensifies anxiety and panic attacks. It also can cause insomnia for anxiety sufferers, because it activates the nervous system. When this happens, your heart rate, blood pressure and stress hormone levels increase.
  5. Your gender plays a role. Guys usually have the upper hand when it comes to genetics. In fact, they are able to metabolize alcohol better than women and lose weight faster. When it comes to caffeine, however, the girls have an advantage. Women process it more quickly and men are the ones who feel the effects more strongly. Don’t be bitter guys!
  6. You’re on birth control. Women taking birth control pills should know they alter the way caffeine is metabolized in their system. Oral contraceptives prevent the loss of important minerals like calcium, zinc and potassium. As a result, the caffeine stays in the body longer and slows down the rate of metabolizing the stimulant.

So is coffee good or bad for you?

Don’t let any of this scare you, though, especially if you are a long-time coffee or tea drinker. When healthy adults consume two cups a day (200-250 milligrams) negative side effects are unlikely. In fact, research has proven there are benefits to drinking both. From antioxidants and nutrients to its ability in speeding the metabolism, improving one’s mood or physical performance, warding off liver disease, reducing the risk of Type 2 Diabetes and protecting the brain against Parkinson’s and dementia, a cup of coffee or green tea receives a thumbs up (sugar and creamer … not so much).
Having said all that, if you are not already a coffee or tea drinker, we don’t suggest you start chugging several cups a day. Conversely, if you suddenly stop drinking your daily brew, headaches and irritability can occur, so cutting back should be gradual.

If your head is buzzing from all this information, the take-a-way is this: drinking a caffeinated beverage isn’t dangerous, nor is it magic. Everyone is different and if drinking a cup or two of coffee makes you feel not great, there is no need to keep trying or to start drinking it just to get the benefits mentioned earlier. If you enjoy your daily brew or two and can tolerate its effects or don’t experience anything at all, you’re lucky and there’s no medical reason to stop. As with anything else – everything in moderation and there can be too much of a good thing, too. Happy sipping!

Your primary care provider (PCP) is your best resource to ensure overall wellness. Make sure you keep your annual appointment and discuss any concerns or issues with him or her during the visit. Together, you can decide the best choices for your lifestyle. Visit UPMCPinnacle.com/PrimaryCare or call (717) 231-8900 if you need a PCP.

Featuring Gayle B. Sisbarro, DO

About UPMC Pinnacle

UPMC Pinnacle is a nationally recognized leader in providing high-quality, patient-centered health care services in south central PA. and surrounding rural communities. UPMC Pinnacle includes seven acute care hospitals and over 160 outpatient clinics and ancillary facilities serving Dauphin, Cumberland, Perry, York, Lancaster, Lebanon, Juniata, Franklin, Adams, and parts of Snyder counties. These locations care for more than 1.2 million area residents yearly, providing life-saving emergency care, essential primary care, and leading-edge diagnostic services. Its cardiovascular program is nationally recognized for its innovation and quality. It also leads the region with its cancer, neurology, transplant, obstetrics-gynecology, maternity care, and orthopaedic programs.

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