What you need to know about caffeine
We all have our favorite caffeine vehicles—yours might be a thick, foamy espresso or a strong cup of Earl Gray tea, or chocolate! I like a good cup of black coffee made with a French press! One way or another, many people feel like they need caffeine on a daily basis—an estimated 80 percent of American adults consume caffeine in one form or another every day.
Caffeine is a stimulant, the most widely consumed drug in the world. Like all stimulants, caffeine consumption needs to be managed. I’m not here to tell you to throw away your coffeemaker, or part with your beloved cup of cold-brewed coffee. But I will give you guidelines to help you manage your caffeine intake, so you can enjoy its pleasures and benefits, and avoid the downsides to sleep, health, mood, and performance that can come with over-consumption.
How does caffeine work in the body?
Caffeine stimulates the body’s nervous system, and affects other systems in the body, including the circulatory, digestive, and excretory systems. Caffeine’s most recognizable effect is usually an increase in alertness and wakefulness. It also creates a short-term elevation of blood pressure. Here are some of the ways caffeine affects our bodies:
Caffeine blocks adenosine. Adenosine is a neurochemical that increases in the body throughout the day. As adenosine builds up, you feel more sleepy and less alert. Caffeine essentially mimics the presence of adenosine in the body, preventing brain cells from recognizing actual adenosine. Caffeine’s effects on adenosine in turn appear to trigger effects on other neurochemicals.
Caffeine increases dopamine. Dopamine is a neurochemical that activates the pleasure centers of parts of the brain. Caffeine increases dopamine similar to the way that amphetamines do. This increases alertness, and also may be part of what makes caffeine so habit-forming.
Caffeine suppresses melatonin. This is one key way caffeine can disrupt your normal sleep-wake cycle. It might surprise you to hear, but caffeine has an even stronger influence on melatonin suppression than bright light. This is also an important way caffeine affects your sleep-wake cycle.
The effects of caffeine aren’t felt immediately—it can take from 25-45 minutes for that caffeine boost to kick in. The effects of caffeine last in the body for several hours. It can take from 6-8 hours for the stimulant effects of caffeine to be reduced by one half.
How much caffeine is right for me?
When it comes to daily caffeine intake, it’s important to think about the amount of caffeine and the time of day you’re consuming it. It’s also important to remember that caffeine comes from many sources, not just coffee. Tea, energy drinks, sodas, and chocolate all count toward your total daily caffeine consumption.
We don’t all respond to caffeine exactly the same way—some of us are more sensitive to this stimulant than others. These guidelines will work for most people to avoid problems with caffeine disrupting sleep, creating jitters and undermining focus.
For healthy adults, the FDA recommends no more than 400mg of caffeine a day. People with high blood pressure or heart problems should speak with their doctor about their caffeine use. This feels like a lot of caffeine to me. What does 400 mg of caffeine look like?
· 4 cups of coffee (standard 8-ounce cups)
· 2 energy drinks
· 6 12-ounce sodas
When you consume too much caffeine, you open yourself up to a number of uncomfortable and possibly debilitating side effects, including:
· Stomach upset
· Muscle tremors
· Heart palpitations
· Elevated heart rate
· Frequent urination
· Difficulty sleeping
Chronic overconsumption of caffeine can lead to a condition known as adrenal fatigue. Symptoms of adrenal fatigue are:
· Weight gain
· Memory loss
· Low sex drive
Adrenal fatigue is also associated with other conditions, including obesity, depression, heart disease and insomnia.
A few words about those mega-size coffee drinks that are so popular these days. An 8-ounce cup of coffee has 100 mg of caffeine. An 8-ounce cup of brewed black tea has about 50 mg caffeine, and green tea, about 30 mg for every eight ounces. Compare those very moderate caffeine amounts with what you’ll find in those super-sized drinks on the market. A 20-ounce coffee drink from some of the popular chains can have 400 mg or more of caffeine. A 16-ounce energy drink can have 150-300 mg of caffeine, or more—a really souped-up energy drink has more than 300 mg of caffeine in an 8-ounce size. To be a savvy caffeine consumer, take into account the specific sources of caffeine you’re using—and when in doubt, order the small drip coffee.
To be clear, I do not recommend you consume energy drinks and soda regularly. These beverages are full of caffeine, and also sugar. I understand they might offer a convenient, occasional pick-me-up. Once in a while—on a long car trip with the kids, let’s say—is fine. But if you’re routinely relying on energy drinks or soda to give you the energy and focus you need to get through the day, there’s likely something else going on that needs your attention: namely, there’s a very good chance you may be dealing with chronic sleep deprivation. Tend to that issue, and your reliance on caffeinated drinks will likely resolve itself.
As far as the timing of caffeine goes, I recommend stopping caffeine consumption at 2 p.m. If you’re an afternoon coffee drinker, switch to decaf at two o’clock. If you like a post-dinner cup of coffee, consider swapping that out for tea. Why so early in the day? Caffeine has a long half-life, between 6-8 hours. That means it can take up to eight hours for half of the caffeine to be metabolized by your body. A 2 p.m. cut-off time can help ensure you’re able to fall asleep by 10:30.
The more caffeine you consume, the less effective it will be in stimulating alertness. That can lead you to consume more caffeine, and make you more vulnerable to negative side effects, including sleeplessness, jitters, and eventually, adrenal fatigue. If you’re a several-cups-a-day coffee drinker who can’t bear to part with the taste and the ritual of coffee, switch a couple of those cups to decaf—you’ll avoid caffeine tolerance and stress on your adrenal glands.
Caffeine addiction, caffeine withdrawal, caffeine overdose
I see many patients who are addicted to caffeine. Caffeine addiction is common among people with insomnia and other forms of sleep deprivation. Their need for caffeine puts them in a sleepless cycle. Caffeine disrupts their sleep, making them rely more heavily on caffeine—which makes it that much harder to sleep the next night. Breaking the cycle of dependency on caffeine can help your sleep and make you feel less fatigued and more focused during the day.
So, you want to scale back on your caffeine intake. Great! How do you avoid caffeine withdrawal? Dropping caffeine cold turkey can indeed lead to some pretty intense, uncomfortable withdrawal symptoms, including:
· Difficulty concentrating
· Flu-like symptoms: muscle aches, nausea and vomiting
Here’s how to scale back on caffeine the smart way:
1. Track your caffeine intake. Spend one week consuming caffeine as you normally do, and keep a very close record of everything you ingest that contains caffeine.
2. Start to reduce caffeine, gradually. The next week, reduce your caffeine intake by about 40mg day—that’s the rough equivalent of about ½ cup of coffee, or a little more than an ounce of dark chocolate. Target first your late-in-the-day caffeine consumption, such as your late-afternoon or after-dinner cup of coffee. Be sure to replace that caffeinated drink with something else, like decaf tea.
3. Continue to reduce your daily caffeine consumption by this same 40 mg a week, until you’ve reached your new goal.
A couple other tips to help you scale back on caffeine:
· Don’t forget to account for ALL your sources of caffeine. That includes chocolate and other desserts (hello, coffee ice cream), drinks, snacks, and medications.
· Consume your most highly caffeinated drinks early in the day, and gradually shift to lower caffeine and then decaf, as the day progresses. Coffee in the morning, black tea at lunch, and herbal tea at bedtime is a great way to go.
Is it possible have a caffeine overdose? Caffeine overdoses are rare, but they can happen. According to scientific estimates, the amount of caffeine needed to trigger an overdose is 5-10 grams, or 5,000-10,000 mg. There have been a small number of deaths involving caffeine in recent years, mostly among younger people.
The rare instances of caffeine overdose, and the much more common problem of caffeine over-consumption are more likely in today’s world because caffeine is being added to so many products—often in high densities. Energy drinks are packed with caffeine. Caffeine powder is available to add to any beverage, and a situation where a measuring error could lead to caffeine overdose, as appears to be the case in the 2014 death of one young man. Caffeine is showing up in all sorts of products, from gum to sweets to snacks.
It’s important to know where your daily caffeine is coming from— pay attention, read labels, and keep it simple when it comes to caffeine. Opt for a regular cup of coffee instead of the mega-sized coffee concoction or caffeine-packed energy drink.
Take a sunshine break
I encourage all my patients, especially those who are trying to break a heavy-duty caffeine habit, to switch from a coffee break to a sunshine break. Light is a powerful mental stimulant. Natural light exposure can increase energy, focus, productivity, mood, and attention span. Research suggests that exposure to natural light and the outdoors may help with attentiveness. Afternoon light exposure has been shown as effective as a short nap in improving some of our cognitive functions.
Well-timed sunlight exposure may have many health benefits, including boosting levels of Vitamin D. It can strengthen your sleep-wake cycle, helping you remain more alert during the day and sleep more, and better, at night.
Instead of heading to the coffee cart or the soda machine in the mid-afternoon, switch up your routine, and treat yourself a 10-minute dose of sunlight.
The benefits of caffeine
Caffeine is not the enemy! Consumed thoughtfully and in moderation, caffeine may deliver a number of benefits to mental and physical health. Studies indicate caffeine may reduce the risk for several different types of cancer, as well as lowering risks for heart disease, stroke and type 2 diabetes. Caffeine may reduce risk for depression. There’s also evidence indicating caffeine may help protect against neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease.
Good news for exercisers: Caffeine may help those of us who work out to burn more calories, and also may reduce muscle pain.
Caffeine also helps with mental performance. It’s been shown to improve memory and reaction time, and increase cognitive flexibility, our ability to switch thinking among topics.
Try a Nap a Latte™
This technique of mine combines a moderate amount of caffeine with a short nap. Sounds good, right? It’s a great trick for when you need to power through a long day, but don’t want to overload on caffeine. Here’s how it works.
Drink an 8-ounce cup of coffee, quickly, by adding a few ice cubes to cool it down. (You’re shooting for around 90-100 mg caffeine)
Lie down and take a 20-minute nap. (Make sure not to sleep for longer than this. Set a timer or alarm if you need to.)
Why this works: During the nap, your body will reduce adenosine, that substance that builds throughout the day and makes you sleepy. (Remember, caffeine fits perfectly into that receptor in the brain.) This then blocks the adenosine build up I mentioned earlier. So, you wake up just as the stimulating effects are kicking in.
Do not take a Nap-A-Latte™ more than two times a week. If you feel you need it more often, you may just need more sleep.
Michael J. Breus, PhD
The Sleep Doctor™