Are You Suffering from a Caffeine Overdose?

While the nutrition facts of coffee and other caffeinated drinks come with some convincing perks, certain experts feel that there are better ways to boost your energy levels. Caffeinated drinks—including tea, coffee, and “energy drinks”—are all complex beverages containing hundreds of biologically active compounds. The health effects of chronic caffeine intake can be wide-ranging depending on the individual.

Since caffeine can stay in your system for four to six hours (and potentially even longer for some people), it’s easy to overdo it and feel panicky, sick, and anxious—all hallmark signs of a caffeine overdose.

Risks of a caffeine overdose:

Although it’s completely legal, caffeine found naturally in coffee and other common drinks is really a stimulant drug. It’s a chemical that affects the central nervous system (CNS) and is considered part of the methylxanthine class of psychoactive drugs. It elevates your heart rate, increases alertness, and changes the way your brain and body work in a number of different ways—some that are beneficial and some that might be dangerous.

What does science tell us about the pros and cons of consuming caffeine?

It all comes down to individual tolerance and how the caffeine is consumed. Current studies disagree about caffeine’s effect on blood pressure, brain activity, hormonal balance, blood sugar levels, and overall mood.

For example, a lot of research has been done regarding the benefits of antioxidant-rich coffee, but it’s possible to read the results in a number of ways. Besides its various potential health impacts, caffeine makes everyone feel a bit differently, so even a small dose can cause a variety of good and bad effects.

Tea and coffee are both natural, unsweetened sources of caffeine—unlike energy drinks and soda. To reduce your sugar and chemical intake while also lowering the caffeine you consume, give up your energy drinks!

How much you’d need to drink to lead to a caffeine overdose:

According to the National Institute of Health, caffeine can be found in:

  • Soft drinks (including Pepsi, Coke, Mountain Dew)

  • Teas (including black, white, green)

  • Chocolate (including hot chocolate drinks and dark chocolate)

  • Coffee and all coffee-containing drinks

  • Some over-the-counter stimulants like NoDoz, Vivarin, Caffedrine, and others

  • Some weight-loss drugs or performance-enhancing “herbs”

The most commonly consumed caffeine drink in the world is coffee. In fact, it’s the second-leading beverage worldwide next to plain water. It’s well-known that too much caffeine can cause nervousness and interfere with restful sleep, but the risks seem to go beyond this. For example, three or more cups can negatively impact hormonal levels and seriously increase symptoms of PMS for some people.

An “excessive intake” of caffeine varies depending on whom you ask and a person’s individual tolerance. For example, when it comes to coffee, some sources define it as drinking more than eight to 10 eight-ounce cups at one time. But for other people, effects can be felt after consuming much less. A “moderate amount” of coffee for healthy adults (which is correlated with health benefits) maxes out at 500 milligrams of caffeine per day, which is about five cups of home-brewed regular coffee.

This “safe” amount is equal to approximately one grande Starbucks coffee (which has about 360 milligrams). For pregnant women, the amount of caffeine recommended or tolerated is less. Most experts recommend no more than 200 milligrams daily during pregnancy.

Although most research shows that the consumption of coffee is a major source of dietary antioxidants and may inhibit disease-causing inflammation, everybody reacts to coffee differently, so risks still need to be considered.

Recent studies in the media often overemphasize the positive effects of coffee without disclaiming the possible, negative side effects. Other research shows that drinking numerous cups of coffee daily might increase the risk of miscarriage, abnormal pregnancy, anxiety, heart problems, and blood sugar issues.

How much caffeine is dangerous and could potentially lead to a caffeine overdose?

In most cases, it’s not coffee that causes caffeine overdose but rather a combination of energy drinks, supplements, and soft drinks—plus coffee or tea, too. For example, there have been a low number of fatalities related to caffeine overdoses, some in fitness and health-seeking individuals taking supplements. It’s one of those all-too-common unhealthy ways to lose weight.

Depending on the consumer, a dose just above 500 milligrams of caffeine could potentially produce symptoms of a caffeine overdose. Some people might feel fine at this amount, while others might feel sick and weak.

Caffeine is classified by the Food and Drug Administration as “generally recognized as safe” (GRAS). Toxic doses are usually considered anything over 10 grams per day for an adult. To put that into context, one cup of coffee contains 80 to 175 milligrams of caffeine depending on the bean and preparation method. So someone would need to have roughly 50 to 100 ordinary cups of coffee to reach a lethal dose and have a true caffeine overdose.

Other caffeinated drinks to consider include:

  • 10-Hour Energy Shot: 422 milligrams

  • McDonald’s 16-ounce Ice Coffee: 200 milligrams

  • McDonald’s 16-ounce Ice Tea: 100 milligrams

  • Coke, Pepsi, Dr. Pepper (or diet varieties) 12 ounce: 45 milligrams

  • Mountain Dew Soda 12 ounce: 55 milligrams

  • 5-Hour Energy Shot: 200 milligrams

  • ACE Energy Drink: 160 milligrams

  • AMP Energy Drink: 160 milligrams

  • Monster Energy Drink: 160 milligrams

  • Average Latte: 150 milligrams

  • Lipton Black Tea: 55 milligrams

  • Matcha Green Tea: 25–70 milligrams

  • Starbucks Bottled Frappachino: 90 milligrams

  • Starbucks 16-ounce Iced Espresso or Cappuccino: 225 milligrams

  • Starbucks 16-ounce Decaf Coffee: 25 milligrams

  • Chai Tea: 47 milligrams

  • Black Tea: 42 milligrams

  • Green Tea: 25 milligrams

  • White, Jasmine, Oolong Tea: 25 milligrams

  • Herbal Tea: 0 milligrams

According to the DSM-5 Criteria, an official diagnosis of caffeine overdose (called “Caffeine Intoxication”) is made when any five of the following symptoms are present: restlessness, nervousness, excitement, insomnia, flushed face, diuresis (you keep passing urine), gastrointestinal disturbance (upset tummy, diarrhea), muscle twitching, rambling flow of thought and speech, tachycardia or cardiac arrhythmia, periods of inexhaustibility, or psychomotor agitation.

Even if you don’t experience a caffeine overdose, just drinking small quantities of caffeine can have negative effects. You know you’ve had too much if you feel dizzy, nervous, and out of control.

Symptoms of consuming too much caffeine, whether or not caffeine overdose is diagnosed, can include:

  • Breathing trouble

  • Changes in alertness or feeling “wired”

  • Confusion

  • Diarrhea, vomiting or digestive issues

  • Dizziness and fainting

  • Fever

  • Hallucinations

  • Increased thirst

  • Increased urination

  • Irregular heartbeat and palpitations

  • Sweating

  • Muscle twitching

  • Rapid heartbeat

Here are some of the most common side effects of caffeine, usually seen in people with a low tolerance due to anxiety, poor digestion, low immunity, or heart problems…

7 Potential Concerns of Drinking Caffeine

1. Has Addictive Qualities

Just like all drugs, caffeine is known to be addictive and is usually used for self-medication, with people altering how much they use based on their needs and built-up level of tolerance. If you’re a coffee drinker and have ever had to go a day or two without your normal “fix,” you know how tough this can be—both on your mind and body. If you have a feeling a bad caffeine habit contributes to your chronic stress and quality of life, it might be time to make a change.

Caffeine withdrawal is a serious, very real reaction to weaning yourself off of coffee and other caffeine-containing drinks. Withdrawal symptoms can include headaches, anxiety, irritability, trouble concentrating, fatigue, digestive issues, and changes in appetite.

Over time, you’ll most likely need more and more caffeine to produce the same energizing effects since your brain and body naturally build up tolerance, which is one reason why some natural health practitioners don’t recommend it. Relying on caffeine for ongoing energy is dangerous because this can exacerbate or get in the way of healing adrenal fatigue and mask serious health issues.

2. Can Cause or Worsen Anxiety

Many people have experienced heightened anxiety due to caffeine consumption, and there’s solid evidence that this is a biological reaction. The side effects of excessive caffeine intake include: increased heart rate, restlessness, anxiety, depression, tremors, difficulty sleeping, excessive urination, and nausea. So if you suffer from ongoing stress and trouble with nervousness, a natural anxiety remedy might be avoiding caffeine in addition to sugar and other stimulants.

If you’re someone who already suffers from high stress levels and nervousness of any kind, you’re more susceptible to caffeine overdose. Some studies have found that when comparing people with panic disorders and general anxiety to healthy subjects, those with existing higher anxiety levels experienced increases in symptoms such as nervousness, fear, nausea, heart palpitations, and tremors after consuming caffeine. Some even said the effects were similar to how they felt during a panic attack.

While coffee is the number one source of caffeine worldwide, remember that sugary energy drinks, most types of traditional tea, many sodas (like Coke), yerba maté, guarana, some herbal treatments, and certain medications also contain caffeine. Weight-loss aids and pain medications, like Excedrin for example, also usually have caffeine (sometimes even in high levels). So check ingredient labels carefully if you know you’re sensitive.

There’s even a small amount of caffeine in decaf coffee, although it’s usually a very low level and a much better choice if you’re prone to anxiety. And don’t forget that caffeine is also found in all forms of real chocolate made from cacao; the darker the chocolate, the more caffeine it contains regardless of being a healthier, lower-sugar choice.

3. Can Cause or Worsen Sleep-Related Problems

Can’t sleep? Due to its stimulating effects, caffeine is known to disrupt sleep and might make insomnia worse in people who are prone to sleep-related problems. Even if you usually sleep well, caffeine might disrupt your body’s natural hormone levels and wake-and-sleep cycles that help promote restful sleep, such as potentially depleting serotonin and melatonin. As a result, you’re more likely to need caffeine to keep you going the next day.

If you have trouble getting good sleep, which is crucial for balanced energy and overall health, try cutting back on caffeinated drinks and having them no later than noon each day (or eliminating caffeine altogether). Making changes to your diet and caffeine consumption can help cure insomnia without drugs just give yourself time to gradually lower your intake to minimize side effects.

4. Impacts Hormone Levels

Caffeine causes the adrenal glands to produce more epinephrine and norepinephrine, and over time this might weaken the adrenals. If you’re someone who suffers from high stress levels, this is yet another reason why caffeine isn’t a good choice for you.

In early research and animal studies, caffeine has also been shown to elevate levels of testosterone and estradiol, which could potentially create hormonal imbalances and complications. To balance hormones naturally, most people need to limit or eliminate caffeine, refined carbs, and sugar.

5. Can Deplete Nutrients and Contribute to Dehydration

Caffeine is a diuretic, so you’ve probably noticed you have an increased need to urinate during the night if you drink caffeine later in the day (which can also negatively affect your sleep). While it’s no longer believed that coffee itself is necessarily dehydrating, it’s still not as hydrating as drinking plain water or herbal tea. So if you sip coffee throughout the day, you’re less likely to drink what your body really needs.

In addition, caffeine might deplete levels of certain key nutrients, including B vitamins, vitamin C, potassium, magnesium, calcium, and zinc.

6. Might Contribute to High Blood Pressure

It isn’t totally clear yet how caffeine impacts blood pressure levels, although this is one of the areas most studied in regard to caffeine’s effects on the body. Some evidence shows that people who drink more caffeine on average have higher blood pressure levels than those who drink none or very little. Other research shows it might raise blood pressure only for a few minutes or even hours, but doesn’t cause ongoing hypertensive disorders.

The level of caffeine in about two or three cups of coffee might also raise the risk for high systolic blood pressureeven in people who aren’t prone to having high blood pressure levels. Another viewpoint is that when someone consumes caffeine regularly, they actually begin to develop a tolerance to it, and as a result, caffeine doesn’t have a long-term effect on their blood pressure.

How you consume caffeine—for example, how you prepare coffee, specifically how much sugar and dairy are added—also makes a big difference. A 12-year study done by Harvard researchers of over 150,000 women published in 2005 in the Journal of American Medical Association found that drinking caffeinated drinks can increase the risk of high blood pressure.

But another very interesting result was that the caffeine-high-blood-pressure relationship was not found to be true with coffee consumption, only caffeinated drinks like sodas. You can see why this raises another issue altogether of the effects of caffeine in combination with sugar on heart health.

To make things even more confusing, there are also some potentially negative consequences of consuming high doses of chlorogenic acid found in coffee. When consuming high levels, usually about twice what an average moderate coffee drinker might obtain, it’s possible that homocysteine levels in the blood could go up. Homocysteine is a nasty inflammatory molecule that is believed to be a risk factor for heart disease, heart attacks, and strokes. The same effects can happen from drinking very high amounts of tea, for example, about two liters a day (which is unrealistic in most cases).

7. Usually Combined with Sugar and Artificial Ingredients

The double-whammy effects of caffeine combined with sugar in sweetened coffee and energy drinks has an even bigger, negative impact on the body than caffeine alone. Even when the caffeine in coffee or energy drinks itself isn’t an issue, the other high-sugar, processed ingredients definitely can be.

For example, most synthetic coffee creamers are full of processed ingredients, sugar, artificial sweeteners, and chemicals. Other popular coffee companions like soy milk, which has become a common replacement for milk in lattes and other coffee drinks over the years, has its own set of issues, as most soy is bad for you.

Even regular dairy milk can cause negative reactions in many people—especially when it’s conventional, non-organic dairy from feedlot-raised cows. Using natural sweeteners and unsweetened coconut, almond or raw milk to cut coffee’s bitter taste is a much better idea. And you already know to stay away from sugary sodas and energy drinks!

This article was originally published on Dr. Axe.

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