Caffeine and Brain Fog

Just because you’re dependent on caffeine to keep you going doesn’t mean that it’s the right choice for your energy and cognitive function.
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When you take that first sip of coffee in the morning, it gives you a rush of satisfaction knowing the caffeine is going to help you perk up and stay at the top of your game throughout the day. That's how it works, right? Maybe. If you have caffeine-induced brain fog, then maybe not.


Just because you're dependent on caffeine to keep you going doesn't mean that it's the right choice for your energy and cognitive function. Caffeine could be the cause behind your constant state of exhaustion — and all the mental lapses that come with it.

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What Is Brain Fog?

The condition known as brain fog is a little hard to define because it's not an actual clinically diagnosed condition. Instead, it's a general term used to refer to a hazy, unclear state of mind. Vail Health describes brain fog common but not normal — it's actually the symptom of bigger health problems.


People with brain fog often have cognitive lapses that a person their age normally wouldn't have (i.e., they are too young for dementia). This could include forgetfulness, confusion and a general inability to focus, pay attention or register information as it comes at them. These brain fog symptoms can make it nearly impossible to function in ordinary situations.

Brain fog is often linked to chronic fatigue syndrome (CFS), which affects about 1 million Americans. CFS presents a problem for health care providers because there's no known cause, diagnostic test or cure. However, neuropsychologists who have studied electrical activity in the brains of people with CFS have deduced the condition is not psychosomatic.


The cognitive aspects of CFS — brain fog — are usually the part of the disorder that is hardest on patients.

Coffee and Brain Fog

What's the relationship between coffee and brain fog? Countless people every day turn to the common stimulant, which is found in coffee, tea, energy drinks and even over-the-counter medicines, for a boost that will help them feel awake and alert.


Once caffeine is ingested, its effects can be felt in as little as 15 minutes. It's absorbed from the digestive tract into the bloodstream and stimulates the nervous system. The effects are felt at their greatest in one hour and remain for several hours later. Six hours after you consume caffeine, about half of it is still in your body. By the time it's completely out of you, nearly 10 hours could have passed.


This is one of the reasons that caffeine can have a negative effect on people's sleeping patterns, according to the Cleveland Clinic, which notes that those with caffeine sensitivities can also have insomnia and feelings of restlessness.


According to a November 2013 study published in the ​Journal of Clinical Sleep Medicine​, 400 milligrams of caffeine can have effects even if taken as early as six hours before bedtime. This causes a person to lose as much as one hour of sleep from restlessness. If a person loses sleep like this over the course of multiple nights, they quickly become sleep deprived.

The cycle continues as you keep turning to caffeine to get you through the day, but then it disturbs your rest that night, causing you to become more exhausted over time. For a 10 p.m. sleep time, avoid drinking coffee past 4 p.m. to avoid sleep disturbances.


Read more:10 Habits That Are Ruining Your Sleep (and How to Fix Them)

To cut back on caffeine, start slowly. If you try to give up too much too quickly, you will crash and go straight back to dependence, per the advice of the Cleveland Clinic. In addition to insomnia, coffee dependence could be causing a rapid heartbeat, increased anxiety and overall feelings of restlessness.


Brain Fog Treatment

If caffeine consumption is interfering with your sleep cycle, logic would suggest that cutting back could help you enjoy more restful nights and struggle with less brain fog and CFS during the day.

A June 2017 report published in the ​Journal of Human Nutrition and Dietetics​ looked at avoiding consumption of potential trigger foods, including not only caffeine but also alcohol, fat, milk and gluten. However despite anecdotal claims that eliminating these foods may help, the study found no evidence to suggest elimination diets will help CFS.



Vail Health does recommend following an overall nutritious diet because blood sugar swings can cause inconsistent brain fuel, thus resulting in brain fog.

If you manage to get eight to nine hours of sleep regularly and still have brain fog, you should talk to your doctor about finding different treatment options. Other commonly recommended brain fog treatment options include relieving stress and anxiety, giving your brain regular stimulation and drinking plenty of water to avoid dehydration.

There's one important alternative to caffeine that Harvard Health emphasizes: exercise. Cardiovascular activity can help your mental process, improve your memory and, in general, wake you up — you don't even have to be physically fit or well rested to get these quick benefits.

Exercise's long-term effects are also great for your cognitive abilities and your mood, and Harvard notes that older patients and those at risk for dementia especially benefit from exercise.

You might not realize how bad your brain fog is until it starts to get better. Caffeine has some benefits when it's used in a healthy way — it can even improve cognitive ability for some people — but, like any stimulant, it should be used responsibly.

Any more than 600 milligrams of coffee (about four to seven cups a day) is way too much for the average adult. Children, teens and pregnant people should consume even less, as they have a much lower threshold.

Too much caffeine can bring about nasty side effects, including jitters, rapid heart beat, high blood pressure, insomnia, nervousness and dehydration. If you're adding sweeteners and flavored syrups to your coffee, you are setting yourself up for even more problems because of the blood sugar swings.

Read more:How Many Cups of Coffee Can You Drink a Day?

Fatigue and brain fog should be easy to treat because they are likely related to your lifestyle. Changing your habits and routine can go a long way in giving you the energy you need to be your sharpest, most alert self who is ready to take on the day.




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