What Happens To Your Body When You Quit Drinking Coffee

If a cup of coffee is an essential part of your morning routine, you're not alone. According to survey data published in the HuffPost in 2011, Americans drink 146 billion cups of coffee each year. And most of us would go to considerable lengths to keep on drinking it. Approximately 55 percent of people "would rather gain 10 pounds than give up coffee for life," while 49 percent "would rather give up their cell phone for a month than go without" their cup of Joe.

But chronic heavy caffeine consumption can have very unpleasant consequences, including anxiety, sleep issues, digestive troubles, and high blood pressure (via Healthline). Caffeine is also habit-forming, and some people simply don't like the idea of being dependent on a substance to function. But deciding to give up coffee — and, more specifically, caffeine — is easier said than done. Caffeine withdrawal is a real thing, and symptoms usually begin 12–24 hours after your last sip and continue for two to nine days (via the Cleveland Clinic). But if you stick with it, you can look forward to many benefits to your physical and mental health.

You'll feel tired and sluggish

The biggest reason people turn to coffee in the morning is for the jolt of energy it gives them. It's not surprising, then, that giving up your daily brew could leave you feeling groggy and lethargic. In a 2012 study published in the journal Drug and Alcohol Dependence, researchers had 213 coffee drinkers fill out a Caffeine Withdrawal Symptom Questionnaire (CWSQ) after only 16 hours of abstinence from caffeine. The results showed that "fatigue/drowsiness" was one of the four most commonly reported symptoms.

Contrary to popular belief, coffee doesn't actually give you energy. Technically only calories can do that, and a cup of black coffee has fewer than five (via Mayo Clinic). What caffeine actually does is prevent your body from registering how tired it is. As a 2012 article in Forbes explains, caffeine molecules have a size and shape that's almost identical to adenosine, a byproduct produced by the normal functioning of your nervous system. Adenosine binds to receptors in your brain, accumulating during your waking hours and eventually triggering sleepiness. When caffeine binds to these receptors instead, adenosine is crowded out and can't get the message to your brain that it's time to rest.

You may be irritable

There's a reason coffee mugs often have witty messages like, "Don't talk to me until this is half empty." Regular heavy coffee drinkers often report feeling grumpy until they've had their morning caffeine fix. According to a 2018 article published in the SF Gate, "consuming 500 to 600 milligrams of caffeine — or more than 4 cups of coffee daily — can lead to mood changes such as anger." Poor sleep because of too much caffeine earlier in the day can also contribute to a grouchy disposition the next morning. But, as the article notes, cutting out coffee can also lead to bouts of anger. Irritability is a common symptom of caffeine withdrawal, especially among those who go cold turkey. Opting to gradually taper off instead can minimize the severity of moodiness and other withdrawal symptoms.

According to the Cleveland Clinic, caffeine withdrawal symptoms begin 12-24 hours after you stop drinking. This means that unless you're drinking caffeinated coffee well into the afternoon and evening, by the time you wake up the next morning, your body is already going through the beginning stages of withdrawal. This explains why some people are downright unpleasant before they've had their morning brew.

You could feel anxious

If you decide to swear off coffee, you may find yourself feeling anxious. According to MedicalNewsToday, caffeine can have a big impact on the levels of the neurotransmitter dopamine, the hormone norepinephrine, and the amino acid glutamate in the brain. When your caffeine intake suddenly stops, the levels of these substances can change dramatically, leading to changes in mood, including anxiety. It can take a few days for your brain chemistry to find its new normal and for anxiety symptoms to subside.

While caffeine withdrawal may cause feelings of anxiety in the short term, continuing to drink coffee could cause or worsen anxiety in the long term. In a 2019 interview with Health, Dr. Susan Bowling explained: "The natural effects of caffeine stimulate a host of sensations, such as your heart beating faster, your body heating up, your breathing rate increasing — all things that mimic anxiety. Psychologically, it's difficult for your mind to recognize that this is not anxiety because it feels the same." Consuming more than 200 mg of caffeine can increase the likelihood of anxiety and panic attacks in sensitive individuals, and caffeine-induced anxiety disorder is a recognized psychiatric diagnosis.

You may have depressed mood

Drinking coffee tends to put people in a good mood, so it's not surprising that giving it up could leave you feeling mopey or blue. And it's not just because you're sad about going without your morning cup. Caffeine withdrawal can cause changes in dopamine, glutamate, and norepinephrine levels in the brain, which in turn can lead to mood changes such as depression (via Medical News Today). The Mayo Clinic noted that stopping caffeine intake abruptly can temporarily worsen depression symptoms for those already diagnosed with a mood disorder.

But regular caffeine consumption may indirectly contribute to depression symptoms long term. The Mayo Clinic explained that poor sleep caused by too much caffeine could worsen depression and suggested that those with a depression diagnosis try limiting or totally cutting out caffeine to see if depression symptoms improve. But some research suggests caffeine may actually decrease your chances of depression. A 2011 study published in the Archives of Internal Medicine followed more than 50,000 women for 10 years to see how coffee consumption impacted depression rates. The researchers found that those who consumed the most caffeine were least likely to be diagnosed with depression.

You could have trouble concentrating

Many people believe that the caffeine in coffee gives your brain a boost, making you mentally sharper and better able to focus. While research suggests that acute caffeine withdrawal can cause dips in cognitive performance, it also calls into question the idea that caffeine improves mental function.

In a 2005 study published in Psychopharmacology, researchers divided participants into two groups. One group abstained from caffeine for three weeks, while another group consumed caffeine daily. The study authors then had all participants perform cognitive function tests first thing in the morning both with and without caffeine. Among the caffeine consumers, performance was impaired when they weren't given any caffeine. They were experiencing withdrawal because they hadn't had caffeine for roughly 24 hours. When they performed the tests after consuming caffeine, their test scores improved. But among the participants who hadn't consumed any caffeine in the previous three weeks, consuming caffeine before performing the tests didn't enhance their performance. The researchers concluded that acute caffeine withdrawal impairs our mental abilities, which can be restored with more caffeine. But caffeine itself doesn't have any magical ability to make you laser-focused.

You'll probably get withdrawal headaches

If you're a long-time coffee drinker who suddenly decides to switch to decaf, it's very likely that you'll experience withdrawal headaches. Caffeine is a vasoconstrictor, which means it causes blood vessels to narrow. In fact, according to a 2009 study published in Human Brain Mapping, blood flow to the brain is reduced by an average of 27 percent among moderate and heavy caffeine consumers. Over time, the body adapts to compensate for this reduction in blood flow. It does this mainly by increasing the number of adenosine receptors on blood vessel walls since adenosine stimulates vasodilation (the enlargement of blood vessels). Caffeine closely resembles adenosine and can bind to these receptors instead, crowding out the adenosine. The body makes more receptors so that the adenosine has somewhere to go and can combat the vasoconstrictive powers of caffeine.

When you suddenly stop consuming caffeine, however, this adaptive system quickly backfires. As the study explained, without caffeine molecules blocking some of the adenosine receptors, adenosine can bind to all of them. This causes an extreme widening of the blood vessels, substantially increasing blood flow to the brain. The rapid shift in blood flow is what causes the headaches commonly seen during caffeine withdrawal.

You may have shaky hands

Like mood changes, tremors can be a sign of both problematic caffeine use and caffeine withdrawal. While tremors aren't a common side effect of caffeine, some sensitive individuals or those with preexisting neuromuscular conditions may notice that caffeine gives them shaky hands. A landmark study published in the journal Neurology in the 1980s found that about two percent of coffee drinkers experience caffeine-induced hand shakiness, while six percent of Parkinson's patients and eight percent of people with a condition known as essential tremor reported that caffeine exacerbated their conditions. As a 2018 article in Self explained, caffeine can cause tremors because it's a powerful stimulant. Sleep deprivation can also cause shakiness, so if caffeine is affecting your sleep, that's a double whammy.

But the National Institutes of Health (NIH) noted that quitting caffeine can also induce shakiness. Ironically, withdrawal can also cause the exact opposite — decreased motor activity. Shaking hands are also a symptom of alcohol withdrawal (via American Addiction Centers). To minimize the chances of tremor, individuals should try gradually tapering down their caffeine consumption instead of suddenly going cold turkey.

You'll sleep better

Once you get past the initial caffeine withdrawal period, you can look forward to a number of health improvements. One of the biggest reasons for going caffeine-free is better sleep. According to the Sleep Foundation, "caffeine can impact the onset of sleep and reduce sleep time, efficiency, and satisfaction levels." It also reduces the amount of time we spend in slow-wave sleep, a deep and restorative phase of the sleep cycle. Because caffeine is a diuretic, it may also lead to disrupted sleep through more frequent nighttime trips to the bathroom. Even caffeine consumed six hours before bed can wreak havoc on your rest. And if the first thing you do after a night of restless sleep is reach for a cup of coffee to wake you up, this only perpetuates the cycle.

A 2016 study published in Nutrients tried to quantify just how much caffeine can ruin a good night's sleep. Participants' caffeine intake was tracked and they completed the Pittsburgh Sleep Quality Index (PSQI), a self-reported assessment of sleep quality. The researchers found that those with the lowest PSQI score consumed an average of 192.1 mg of caffeine daily, while those with the highest scores and best sleeping habits consumed only 125.2 mg.

Will your bones get stronger?

You may have heard that coffee can "stunt" your growth. According to National Institute of Health's Office of Dietary Supplements, the caffeine in coffee (and tea) can "modestly increase calcium excretion and reduce absorption." However, this loss is not significant (2 to 3 milligrams of calcium). "Moderate caffeine consumption (1 cup of coffee or 2 cups of tea per day) in young women has no negative effects on bone," the institute confirmed. And you shouldn't blame this beverage for your short stature. As Harvard Health Publishing put it plainly: "This popular beverage doesn't stunt your growth."

While it was once thought that drinking high amounts of coffee could lead to bone loss, the Harvard publication explained that "it turned out that people who drank more coffee also drank less milk and other calcium-containing beverages. So it was probably the dietary intake of calcium and vitamin D among coffee drinkers, not the coffee, that increased the risk of osteoporosis."

While your bones won't automatically get stronger just because you've cut out coffee, if you've replaced the beverage with more calcium-rich products you could just help prevent against osteoporosis (via WebMD).

You'll look younger

Move over facials and expensive serums; cutting out coffee just might be what your skin needs to look its best. As New York City dermatologist Dr. Deborah Wattenberg explained in a 2011 interview with Today, "caffeine ... act[s] like a diuretic and prevent[s] you from holding on to water, so your skin looks sort of prune-like. It can get dry and get washed out." Wattenberg pointed out that lack of sleep is also a complexion killer, so the better sleep that comes with a caffeine-free life can also give your skin a boost.

A 2014 study published in Drug Design, Development and Therapy found that caffeine prevented skin cells from producing collagen, the protein that gives skin its structure and suppleness. It appears to do this by inhibiting an enzyme needed for collagen production called prolidase. Caffeine also appeared to prevent proper DNA synthesis within skin cells. Hyaluronic acid (HA), a substance that appears to have some protective effect on collagen formation, wasn't able to reverse the damage to skin cells caused by caffeine. Although caffeine may have some antioxidant and anti-inflammatory properties, its detrimental effects on collagen make it a net negative for your skin.

Your teeth will be healthier and whiter

Giving up coffee may give you something to really smile about, since your morning brew is bad for your teeth in a number of ways. According to Mouth Healthy, caffeine can dry out your mouth, robbing it of the saliva that helps protect tooth enamel. Coffee can also cause unsightly stains on teeth. And if you're used to drinking your java on the sweeter side, the sugar isn't doing your teeth any favors either.

But it isn't the caffeine itself that leads to coffee stains. As Healthline explained, "Coffee contains ingredients called tannins, which are a type of polyphenol that breaks down in water ... Tannins cause color compounds to stick to your teeth." Even light coffee consumption — just one cup a day — is enough to leave unsightly yellow stains. The acids in coffee can also erode tooth enamel over time. That's especially true if you're in the habit of brushing your teeth immediately after your last sip, as the toothbrush's bristles simply scour the teeth with acidic coffee. If you can't bring yourself to give up coffee altogether, Healthline recommends waiting at least 30 minutes to brush your teeth and rinsing your mouth out with water beforehand.

You won't have to go to the bathroom as often

Giving up your morning go juice may help you, well... go ... less. As Houston Metro Urology explained, caffeine inhibits the production of anti-diuretic hormone (ADH). ADH is a hormone produced by the pituitary gland that signals to the kidneys that the body needs more fluid. The kidneys respond by reabsorbing more fluid back into the bloodstream rather than sending it off to your bladder. By inhibiting ADH, caffeine tricks your kidneys into thinking that your body has the hydration it needs, leading to excess urine production.

Coffee is also well-known for bringing on bowel movements, but it's unclear why. According to a 2019 article in Health, neither the caffeine nor the warmth of coffee are responsible for inducing a poo. Something in coffee appears to stimulate receptors in your gastrointestinal tract, causing your stomach and intestines to contract the way they would after a meal. These coffee-induced contractions can begin as quickly as four minutes after taking a sip of coffee. But researchers are still unsure which compound in coffee is giving your guts the green light to start moving things along at such a rapid pace.

You'll find hormonal balance

Is coffee throwing your hormones out of whack? According to a 2012 study published in The American Journal of Clinical Nutrition, the answer for some women appears to be yes. The researchers followed 259 women for two menstrual cycles, collecting data on their caffeine intake and taking blood samples to measure estrogen levels. They found that although caffeine intake of 200 mg per day or more decreased estradiol (the most common type of estrogen in premenopausal women) in white women, it increased estradiol levels in Asian women.

According to the Hormone Health Network, both low and high estrogen levels can cause problems. Symptoms of low estrogen levels in women include infrequent or absent periods, hot flashes, mood swings, low libido, difficulty sleeping, and dryness of the vagina or skin. On the other hand, estrogen levels that are too high can cause weight gain, menstrual irregularities and severe PMS, noncancerous lumps in the breasts or uterus, low libido, fatigue, depression, and anxiety. Medical News Today noted that high estrogen levels can also increase a woman's risk for certain conditions, including "thyroid diseases, blood clots, heart attack, stroke, breast cancer, [and] ovarian cancer."

Your blood pressure could improve

If you need to get your blood pressure under control, quitting coffee may be the sacrifice you need to make. According to the Mayo Clinic, "caffeine can cause a short, but dramatic increase in your blood pressure, even if you don't have high blood pressure." It's unclear, however, why caffeine increases blood pressure. One theory is that it blocks a hormone responsible for keeping blood vessels dilated. Another possibility is that caffeine, a stimulant, causes your adrenal glands to produce excess adrenaline. One of the "flight or fight" hormones, adrenaline causes blood vessels to constrict, increasing blood pressure.

A 2005 meta-analysis published in the Journal of Hypertension reviewed data from a number of studies examining the link between either coffee or straight caffeine and blood pressure. Across all the studies, coffee and caffeine raised systolic pressure an average of 2.04 mmHg and diastolic pressure an average of 0.73 mmHg.

The Centers for Disease Control and Prevention (CDC) defines high blood pressure (hypertension) as a systolic pressure of 130 mmHg or higher or a diastolic pressure of 80 mmHg or higher. The CDC noted that 45 percent of American adults have hypertension, putting them at increased risk for heart attack and stroke.