Caffeine is awesome, but it’s also a drug—and you’re probably addicted. Yeah, sure, you’ve heard it before, but research shows that you’re not listening. According to a new study, a significant number of caffeine users are dependent enough on the drug to have withdrawal symptoms when they don’t consume it, and have trouble cutting down even when they want to. This becomes dangerous when people need to cut down on caffeine use for reasons like heart disease or pregnancy—especially because the stimulant is largely unregulated.
The study analyzed previous research on caffeine dependance, officially known as Caffeine Use Disorder. Based on current diagnostic criteria (it’s listed in the DSM-V as a condition that warrants more investigation, though the authors of the study argue that it should be recognized as a clinical problem), you’ve got it if you’ve experienced these three symptoms within the past year:
1. You have a persistent desire to give up or cut down on caffeine use, or you’ve tried to do so unsuccessfully.
2. You continue to use caffeine despite knowing it contributes to recurring physical or psychological problems for you (like insomnia, or jitteriness).
3. You experience withdrawal symptoms if you don’t have your usual amount of caffeine.
Additional symptoms include taking more caffeine than you intend to, failing to fulfill your obligations because of caffeine use or withdrawal (so, being late to work because you drank coffee and stayed up too late, or not being able to focus because you missed your morning cup), developing a tolerance to your usual levels of caffeine, craving caffeine, and spending large chunks of time obtaining it.
It isn’t necessarily a tragedy that you and I are both (almost certainly) caffeine addicts: The researchers concluded that healthy adults can have as much as 400 mg of caffeine a day, which is the caffeine equivalent to around two or three 8-oz cups of coffee (a 16-oz serving of Starbuck’s Pike Place brew, for example, contains 330 mg). In the US, adults consume an average of 300 mg a day (pdf). Of course, other countries have higher averages—in Finland, the average adult consumes the daily maximum of 400 mg, indicating that many are consuming more, and they aren’t even the leading consumers of coffee. But in most countries, the average healthy adult is right on the mark for safe caffeine consumption. The trouble starts when they stop being so healthy.
When pregnancy or a health condition warrants a caffeine cut (pregnant women, the study advises, should cut their intake in half to 200 mg a day at most), your addiction will get in the way: The studies analyzed showed that significant stress and impairment occurred in a median of 13% of people going through caffeine withdrawal. Withdrawal symptoms can vary widely in severity, but generally include headaches, nausea, anxiety, fatigue, inability to focus and irritability. And studies of pregnant women showed that many of them—particularly those who self-identified as being dependent on caffeine—continued to consume high levels of the drug despite knowing the potential health effects, which can include low birthweight and even miscarriage.
What’s worse is that many people don’t even know how much caffeine they consume, the authors say. While some products voluntarily list their caffeine content, there’s no labeling standard. Caffeine comes in many forms these days—pain killers, mints, soft drinks,and all sorts of candy—but even a product as seemingly simple as coffee can vary widely in its caffeine content, with many consumers none-the-wiser. So find out how much caffeine is in your daily caffeine fix; it may be worth cutting back slowly, to avoid the headache if you need to limit your caffeine intake in the future.