Estimated read time: 5-6 minutes
Editor's note: Tuesday, Deseret News looks at the use of caffeine in sports.
SALT LAKE CITY — When Tillie Uribe feels that first twinge of a migraine coming on, she reaches for caffeine. Some of her headaches are doozies.
Her doctor suggested that caffeine's an easy way to at least try to head off the ache before it really digs in. She's found it often works pretty well, narrowing blood vessels in the brain and short-circuiting the misery. So when the lights appear to flicker or she sees an aura — sure signs a migraine is imminent — she says she'll reach for coffee, tea, soda, whatever caffeine is handy.
On the other hand, Uribe, a kindergarten teacher from West Jordan, normally can't tolerate caffeine after about 4 p.m. True for many people, caffeine late in the day keeps her awake. She also has had peripartum cardiomyopathy for decades. That's a rare form of heart failure that can occur late in a pregnancy, so she has to be careful how much caffeine she consumes. The stimulant could be bad for her heart.
For Uribe, caffeine is both a potential blessing and curse.
For many other people, caffeine is something of a mystery. Studies — and there are scads of them — sometimes contradict each other. Products containing caffeine use positive words like "energy" and "focus," but ignore potential downsides. The truth is, caffeine can be positive or negative, depending on how it's used.
And also depending on how a person metabolizes caffeine and if one's particularly sensitive to the effects and ... well, there are many factors when it comes to caffeine's effects on individuals. Here's some of what I learned when I asked various health practitioners about caffeine.
What is caffeine?
Caffeine is a stimulant that's naturally found in 60 different plants, including in coffee beans, tea leaves, guarana berries, yerba mate leaves and cacao beans. It can also be manufactured with this recipe: eight carbon atoms, 10 hydrogen atoms, four nitrogen atoms and two oxygen atoms. That's often its route into supplements, foods, beverages and medicine.
Because it's a stimulant, caffeine's most frequently used as a performance-enhancing drug, not only in sports but for "just work and life," said Dr. Brett Toresdahl, board certified in family medicine, with a sports medicine certificate. He's also an associate professor and director of research for the Division of Sports Medicine in the orthopedics department at University of Utah Health. Caffeine, he said, "reduces fatigue and improves alertness."
Most people get caffeine by drinking it and there's a ton of difference in how much a cup of various caffeinated beverages contain. Medline Plus reports that in general an eight-ounce cup of coffee has 95-200 milligrams of caffeine, while a 12-ounce can of cola contains 35-45 milligrams. An 8-ounce cup of green or black tea contains 14-60 milligrams. Energy drinks are all over the place. Medline Plus says they range from 70-100 milligrams for eight ounces. But when I went shopping for caffeinated energy drinks, I found some 12-ounce drinks that noted 200 milligrams of caffeine. And that's just the added caffeine. If the product also contains natural caffeine from coffee, tea or other plants, that may not be quantified on the label.
"I think that it'd be important for folks who are considering or reconsidering their caffeine use to understand that there are different concentrations of caffeine in beverages," said Toresdahl. "There's a huge range between sodas, energy drinks, different ways coffee's prepared. It's important that people are aware of their cumulative caffeine intake."
Caffeine may also be in surprising places. "Caffeine can be found in unexpected products like certain gums, energy bars, some pain relievers, sports drinks, flavored waters and even in some ice creams and yogurts," said Chris Mohr, fitness and nutrition advisor at Fortune Recommends Health. "Always read labels carefully to avoid having too much, which may lead to unwanted side effects."
Caffeine even has unexpected effects unrelated to health. An international study in the Journal of Marketing found consuming caffeine before shopping leads people to more purchases and spending. The effect is stronger for "high hedonic products" like scented candles, cologne and decor. Caffeine doesn't impact whether you buy a notebook or a laundry basket.
How much is too much caffeine?
People process caffeine differently, said Sarah Dehoney, a neurology clinic pharmacist at University of Utah Health. Some can drink a cup of coffee right before bed, while others who consume even small amounts early in the day struggle to sleep at night.
"Metabolism in people's bodies varies, so some may be more sensitive to side effects. We say, 'Start low, go slow' and watch. Someone who's super sensitive might feel their heart is racing. They might have anxiety or nervousness, or they might be really irritable. They might get hungry, like hypoglycemic, have trouble sleeping, have an upset stomach and increased urination. Those are signs you are taking too much or your body isn't eliminating it quickly enough and you need to decrease your dose next time," Dehoney said.
That the amount and personal tolerance is so variable leads to contradictory views of whether caffeine is helpful or harmful, said Michelle Routhenstein, a cardiovascular dietitian and author who created New York-based EntirelyNourished. Caffeine in coffee can cause one person's heart rate or blood pressure to rocket or trigger heart palpitations. Another could have two or three cups of coffee without those effects or gastric issues.
"There's a sweet spot," Toresdahl said, "that's different for everybody in terms of how much caffeine is helpful. And that line that crosses into being unhelpful is different for everyone in terms of tolerance for the substance." He said caffeine can lead to dehydration, especially while exercising outside when it's hot. Caffeine can also make people anxious or jittery.
