Caffeine Doesn’t Affect Me / What Can You Do About It

a man leaning on a table with a cup of coffee in his hands asking himself why caffeine doesn't affect me

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Why do some people seem to get more energy from a cup of coffee while you sit there wondering why caffeine doesn’t seem to have any effect on me?

It affects people differently for a variety of reasons. But you need to be careful, as there have been instances of accidental deaths due to caffeine overdose.

Not to worry, we’ve listed all the reasons why your favorite beverage may no longer give you the same effect and what options you have to fix it.

caffeine molecule structure (atomic model) with the word caffeine written at the bottom out of coffee beans.

What Exactly Is Caffeine?

It’s a psychoactive drug consumed by millions of people all around the world. Despite its stimulating effects on the brain, it is not regulated, is consumed in high volume, and is generally considered safe.

Caffeinated drinks stimulate your central nervous system by blocking extra adenosine receptors that bring sleepiness in individuals and release dopamine hormones to give you a random jolt of energy. 

It’s an alkaloid and resembles some parts of your DNA and RNA. it has many health benefits, including increases in energy, reducing/killing cancerous cell growth, suppresses your appetite, and helps you lose weight. 

Too much coffee can also cause dangerous psychological side effects, including anxiety, lack of quality sleep/insomnia, depression, withdrawal symptoms, and addiction. 

Thus, it’s recommended to drink coffee in moderation.

It’s advised not to consume more than 400mg of caffeine in a single day and to do it in multiple doses. This is why you should have a cup of coffee multiple times a day and not too many at one time.

This goes for energy drinks, instant coffee, or different brewing methods.

Consumed caffeine above 500mg can lead to serious health issues and or an overdose if consumed at once. 

The most popular sources are coffee beans, black tea, teas, cola, cocoa, chocolate bars, energy drinks, etc. Coffee beans have the highest quantity and are considered one of the most consumed beverages globally. 

A cup of coffee can have 80-150mg (Sometimes more). So limit your daily intake to 3-5 of depending on the amount of caffeine. 

How caffeine works?

Once you consume caffeine through coffee, your stomach and intestine take 30-45 minutes to completely (99%) digest and absorb it in the bloodstream. 

Once it is absorbed in the bloodstream, it travels throughout the body and reaches the brain. In the brain, it competes with adenosine molecules. This is due to how caffeine binds to the adenosine receptors.

  • Caffeine enters your bloodstream through the stomach and intestine. 
  • Once reaching the brain, it meets the adenosine receptors. These receptors are responsible for sleep. Caffeine attaches/binds itself to these receptors and travels south to the liver. 
  • The liver is where caffeine is metabolized and broken into smaller substances. 

What are adenosine receptors?

Adenosine receptors are responsible for a person’s sleepiness and the blockage of Dopamine. Adenosine connects to four receptors; A1 and A2A receptors are reasonably related to caffeine and caffeine’s effect on the body. 

Receptors are transducers responsible for converting any energy into electrical impulses that further travel throughout your body for actions. They are popular proteins and are often termed as the first messenger. 

They are responsible for initiating signaling to the brain for internal effects on the body.

A1 receptors send an electric impulse to the brain to create certain relaxation in the muscles and sleepiness when attached to an adenosine compound.

Similarly, the A2A Receptor is responsible for dopamine release. Therefore, once adenosine binds to A2A receptors, it blocks the production of Dopamine. 

Usually, the brain releases adenosine when your body has been tired and needs physical and mental relaxation. Bringing sleep is the brain’s acknowledgment for the refreshment of the body, mind, and soul. 

Can you be immune to caffeine

Heavy coffee drinkers will build a high tolerance after prolonged consumption. However, with time, your body and brain start to become immune to the effects and this will cause them to diminish after a while.

Universally, caffeine or any drug/food can feel good/taste good/be satisfying when consumed in a limited quantity. However, when consumed daily and heavily, your brain adapts to the effects leading to the same amount giving you diminished effects.

The second popular group of people who are immune to coffee is people with different genetics than others. This is the hardest category to achieve the desired effect.

These genetic changes may include non-sticky adenosine receptors that cannot bind with caffeine. The second genetic alteration is fast enzymes that metabolize caffeine in the liver too fast.

If you want an extra kick for your workout and energy, try pre-workouts with high caffeine.

Tired college student

Reasons Why Caffeine Doesn’t Affect You.

There are many reasons why you can have diminished results. However, you’re able to change some of them, and others are permanent.

Not enough sleep

Being sleep-deprived for 3-4 days starts to reduce the effect of caffeine.


After consuming too much caffeine, sleep deprivation is the most significant side effect. Unfortunately, when your eyes beg to be closed, your brain starts to release more adenosine to try and force you to sleep. 

Now It’s war.

The more you consume to stay awake, the more adenosine your brain will produce. 

Lack of sleep will only bring out the negative effects of caffeine. So, drink it when you need to get rid of unwanted tiredness in the morning or afternoon.

Don’t consume coffee at night or when you are excessively drained emotionally, physically, and mentally. Rest is equally essential for your body, and your brain will do everything to provide it to you every day.

You’re drinking too much caffeine.

Too much of anything is never good. When you consume too much, you allow your brain to adapt to it.

When a heavy coffee drinker is asked to go cold turkey (get rid of caffeine for minor periods), they experience withdrawal.

These symptoms occur because your body craves the dopamine release that caffeine provides. 

Unfortunately, heavy drinkers get immune, and it soon stops working as a stimulator; this includes energy drinks.

So, limit your intake to up to 400mg per day to experience the increased Dopamine without the adverse side effects.

Also, drink it in incremental doses of 100mg throughout the day. Don’t consume all 400mg in one sitting. 

Young happy business man holding a funny huge and oversized cup of black coffee in caffeine addiction concept isolated on even background

You’re not drinking coffee enough.

The effects of caffeine from your morning cup of coffee start to kick in your central nervous system very quickly. Expect it to start functioning within 30 to 45 minutes.

Since it takes 30-45 minutes to absorb into your bloodstream, the results will be subtle once they reach your brain if you aren’t drinking enough.

Sometimes, you might order a large coffee but experience little to no energy. The brewing method will determine the amount of caffeine. 

  • Espresso is a small beverage but has a caffeine content of 40mg per one-ounce shot.
  • Drip coffee is a larger beverage and has 100-120mg. Drip coffees are usually 8oz in volume. 
  • Tea has even less. A tea usually has 40-60mg or even less. 
  • Hot cocoa: has 14mg
  • Fermented tea: 10mg

So, you might think you’re drinking a highly caffeinated beverage, but in reality, you’re drinking too little caffeine to have a positive impact.

A precise amount of caffeine to consume per dose is 100mg to have lasting effects. This is because 100mg stays in your system for 5 hours. 

Your specific genetics

Genetics always plays an essential role when determining the effect of coffee on your brain and body.

Two essential genetic involvements occur.

  • When caffeine sticks to adenosine receptors. 
  • When caffeine reaches the liver to be metabolized. 

Adenosine receptors

Genetics leads to different structured adenosine receptors known as an inhibitory neurotransmitters. Some individuals will have very sticky receptors that will trap them easily. Others might not be as sticky and not attach to caffeine properly. 

When caffeine doesn’t stick to receptors easily, it cannot correctly block them from inducing sleep. Thus, people with less sticky receptors might not have the increased energy as others do.

How your body metabolizes caffeine

The second genetic issue that affects caffeine consumption and its effects is your metabolism. CPY1A2 is an enzyme responsible for the breakdown of caffeine. 

Individuals have different genes for these enzymes. Some individuals have less capable CPY1A2 enzymes than others. 

People that drink coffee with less active CPY1A2 enzymes will metabolize it slower than people with more active enzymes.

The slower your metabolism of is, the longer it will affect your body with increased Dopamine and energy. Conversely, people with a fast caffeine metabolism will break it down faster, thereby killing its effects sooner. 

Your caffeine tolerance is too high.

Whether you’re a coffee-lover, or fond of an energy drink, the effects of caffeine will diminish if you’re consuming too much, and no matter how much caffeine you drink won’t help this.

With prolonged exposure to coffee, faster metabolism, and non-sticky receptors, your body soon starts to build a tolerance against caffeine. This happens when you become a regular and avid coffee drinker. 

With everyday caffeine, your brain becomes tolerant by creating more sleep receptors and speeding up your metabolism. 

Once your tolerance is too high, it starts having little effect whatsoever on your body and brain.

You might need to drink a heavy dosage to feel that punch again, and the increased dosage won’t last long, either.

If you have reached a particular stage where caffeine does nothing to you and you demand a more significant portion of caffeine consumption, it’s best to take a break. 

To avoid increasing your tolerance, limit your intake. 

  • Only drink it in the morning when you need it most
  • For a change, drink decaf coffee if you don’t want to give up the ritual or flavor. 
  • Drink tea as a coffee substitute. Many kinds of coffee taste like tea
  • Switch to fermented coffee for a while. Fermented coffee has very little caffeine. 

Medical history

Caffeine has a long history of adverse effects when combined with other drugs since it’s considered a drug itself. It has been shown to affect certain drugs’ absorption, assimilation, efficacy, and excretion. 

Every drug/medication will mix with it differently. Some drugs with similar effects, like caffeine, will increase their effectiveness as a drug in your body. Other drugs might suppress its activity. 

You might experience increased or lower blood pressure, strokes, seizure, and heart attack. Thus, always consult your doctor before consuming it.

You are taking supplements with caffeine in them.

Caffeine supplements account for 100mg-200mg of caffeine in one dose. If you take supplements with caffeine, your brain will detect it sooner than coffee, which is a slower process. 

If you continue consuming caffeine supplements daily, you will accelerate your tolerance against the drug. Taking these supplements is different from the natural form, but the after-effect and tolerance remain the same. 

You should either consume coffee or supplements but never both. Try to create a balance. 

A picture of a lot of prescription pills being dumped onto a table in reference to If you have ever asked yourself why caffeine doesn't affect me it may be due to the prescriptions you are taking.

You add too much sugar when you drink coffee.

Although different studies support different outcomes, no one can deny that sugar makes you sleepy. You are more likely to feel tired after consuming a sweet dish than not. 

Sugar binds the effects of orexin, a chemical that stimulates the feeling of being awake, making you sleepy, tired, or lazy. So, it reduces caffeine’s effect when consumed together or separately. 

When you add milk and sugar to your coffee, you are actually hindering the positive effects, creating a sleepy, lazy impact on your brain. 

Like sugar, milk also contains tryptophan and melatonin, both of these chemicals are responsible for feeling sleepy and managing the sleep-wake cycle. 

Also, heavy drinks make you feel dizzy or lazy because they contain tryptophan, which increases sleepiness in individuals. 

Please note: Sugar or milk doesn’t dilute caffeine; they only dilute the beverage. It is still present in the same quantity as before. Sugar and dairy oppose the after-effect of caffeine inside the body when metabolizing and increasing your blood sugar.

A man with a crazy look on his face figuring out what to do since he isn't affected by caffeine

What should you do if caffeine doesn’t work for you?

Caffeine isn’t the only energy source; many things can get you through the day without that lazy or sleepy feeling.

Exercise daily

Exercising releases many active hormones like Dopamine and serotonin. When you exercise, you are awakening your body and stimulating your muscles for the day.

Exercising is a natural anti-depressant and will give you natural energy. 

It’s believed that exercising tires you, but there’s only a little truth to that. You don’t have to perform intensive exercise sessions to feel energized. 

A simple brisk walk, jogging, playing with your dog, or a casual Zumba session will allow you to dissipate laziness and tired muscles. Light exercising does not tire your body but energizes your muscles for the day. 

Keep a consistent sleep schedule.

Sleep is equally essential. Your brain needs rest to heal and repair itself. When you change your sleeping pattern every day, you are confusing your body and your brain. A human being needs seven to nine hours of sleep every day to function correctly.

Try to go to sleep at the same time every night and wake up at the same time in the morning.

This will allow your brain to set an internal clock for your sleep schedule.

Use natural herbs

Natural herbs have many health benefits, including increasing blood circulation, digestion, immunity, strength, the ability to fight off diseases like the common cold, and boosting energy.

Herbs have been used for their health benefits by people for centuries. 

Before synthetic and natural medicines, herbs were used to mend issues like open wounds and internal issues. So, switch your daily cup of coffee with herbs. 

You must have heard of herbal teas, and they are an excellent substitute for coffee, and many herbal teas taste like coffee if you want the same flavor profile. 

A fridge full of whole foods, including fruits and vegetables. This will help you increase your energy if caffeine doesn't help you wake up.

Eat a healthy diet

Your diet is the primary source of energy, so it should never be compromised. Whatever food you intake accounts for the calorie you’d need to function correctly throughout the day. 

When you don’t provide enough HEALTHY calories to your body, you are bound to be tired and sleepy because your body has no power to carry on with the day. Thus it’s essential to eat healthily. 

Stay hydrated

Water and fluids are essential and a necessity for your body. Without enough water, you will experience fatigue and low energy. It’s no secret that the human body is 60% water and cannot survive without it. 

Water and fluids are necessary for digestion, cellular health, healthy libido, consistent energy, blood circulation, and muscle repair. 

So, hydrate your body with enough fluids. If water is too much to drink all day long, increase your capacity by one glass every day. Along with water, eat juicy fruits like watermelon, oranges, etc. 

Take a nap

To work efficiently, you must rest equally! Our body demands 8-9 hours of sleep every day. Apart from that, it doesn’t hurt to snatch some extra minutes/hours now and then. 

Napping little lets you rest after a tiring day. This nap eases away your tiredness and boosts you for the additional hours of the remaining day. 

Coffee substitutes

There’s no doubt that caffeine has many health benefits, but it comes down to how readily you can accept it and how your body receives it. 

Many individuals have a high caffeine sensitivity to coffee, and it’s not the only thing that affects their health but what they add to the coffee. The acidic qualities can hurt people also; if this is happening to you, read my review on low acid coffee like LifeBoost.

Most coffee substitutes might have a little caffeine content, and some might be 100% free of it. However, if you are strictly asked to prohibit caffeine, it’s best to choose products with zero in them like herbal teas. 

Assortment of fragrant dried teas and green tea on a dark wooden table as an alternative if caffeine doesn't affect you.


Like coffee, tea is one of the most preferred hot and cold beverages to have ever existed. Tea is the specialty of China and East Asia, but it’s valued all around the world. 

Tea is brewed like traditional coffee by blending tea leaves with hot water and straining the end product.

Tea is a naturally stimulating beverage made from the dried leaves of camellia Sinensis, a native shrub to Asia. These leaves are cultivated and dried for tea preparation. 

Tea is similar to coffee in a lot more ways than you can think. First, they have the exact brewing mechanism and aromatic hot beverages. Plus, you can also drink iced tea, just like cold brew. Cold brew also has less caffeine in it than hot coffee.

Some teas taste very similar to coffee.


Cocoa or cacao beans are the product of the Theobroma cacao tree, a small tree native to Mesoamerica. Don’t confuse these cacao beans with coffee beans because both have different flavor profiles. 

Cocoa beans are used to produce chocolate, cocoa powder, cocoa butter, and chocolate drinks. On the other hand, coffee is made from coffee cherries that are used to brew coffee beverages. 

But despite their purposes, both share a very similar flavor profile. Cocoa has the same nutty, earthy, flowery flavor profile but is naturally sweeter.

Coffee has the same flavor profile with slightly acidic characters, bitterness, and less sweetness. In addition, coffee is more fruity than cacao beans. A six-ounce hot cocoa beverage has only 5mg of caffeine or even less. 

Acorn coffee

Acorn coffee isn’t necessarily coffee, but its taste is very much similar to coffee. Acorn is an excellent coffee substitute with a bitter-sweet earthy profile, a nutty body, and the slightest hint of acidic characters. 

Many big tea companies use Acorn as the main component while producing coffee-like beverages. Acorn, when mixed with other coffee-like elements, creates some of the best coffee substitutes. 

After leaching, acorn sweetness can be compared to maple syrup, and its bitterness is mute but visible. Luckily, Acorn is 100% caffeine-free, and you can consume and brew it just like coffee. 

Chicory buds that you can put in to tea to give it a coffee like flavor

Add chicory to your tea/beverage.

Chicory has a profound history of being used as a coffee substitute. Chicory roots are dried and crushed to give away a similar appearance, just like tea. To this date, french breweries still use chicory to add to the taste of the coffee. 

Chicory has a darker and more robust taste compared to dandelion roots. Dandelion roots are another substitute for coffee and belong to the same family as the chicory) 

Unlike dandelion roots, chicory has a familiar bitter-sweet taste, just like coffee. However, the sweetness is mild, along with many spicy and earthy undertones.

Does caffeine increase dopamine?

Caffeine is a similar drug to amphetamine and methylphenidate because all three of them work as stimulants.

Stimulants are responsible for faster communication between the body, brain, and actions. It speeds up these actions, excites your system, increases alertness, and gives bolts of energy. 

Dopamine’s release is the reason behind those bolts of energy. So, to answer, yes, it does release Dopamine and in a fair amount, too.

Where is caffeine found?

It is a natural drug found in many plants, seeds, beans, leaves, and roots.

Coffee beans are considered the richest natural source. Different species of coffee produce different amounts. The content can depend on the beans’ type, origin, species, etc. 

Two notable species of coffee are robusta beans and single-origin Arabica beans. Robusta is richer in caffeine and has double the content compared to Arabica. 

The good and bad of caffeine

Despite the pronounced myths about coffee and caffeine, both have many health benefits. Especially when consumed in the correct quantity, helps in many prospects. 

Please note: It can be fatal when consumed at high quantities of 500mg at once. Therefore, it’s recommended to drink caffeinated beverages in batches of 100mg spread throughout the day, not exceeding 400mg in total.


  • Dopamine surge and increase in energy and alertness
  • It helps increase your memory power and, speeds up your delayed senses’ thought processes, and fastens reflexes. 
  • Studies claim it can prevent Type 2-Diabetes, liver diseases, Parkinson’s diseases, and many others. 
  • It’s reported to fight off cancerous cells’ growth and help prevent liver and colon cancer. 
  • It can help you lose weight faster and metabolizes unwanted weight more quickly. 
  • It has many side antioxidants. 


  • It’s addictive and may lead to non-stop withdrawal symptoms that adversely affect your physical and mental health. 
  • These withdrawal symptoms may include fatigue, depression, anxiety, and psychological swings.  
  • It increases the chances of blood pressure and isn’t suitable for people already suffering from high blood pressure.
  • Tannins in caffeine can turn your teeth yellow. 
  • caffeine is a diuretic so you have to drink water in order to stay hydrated.
Pregnant woman with laptop sitting on the sofa in the room

Who should and shouldn’t use it?

Caffeine has many benefits and side effects. It can depend on your physiological makeup, health, well-being, and capability to metabolize coffee/caffeine. 

  • If you are someone with weak digestion and a sensitive stomach, you shouldn’t consume it. it can irritate people with weak digestion. 
  • People with high blood pressure shouldn’t drink it because it enhances blood pressure and heart activity. 
  • People with irregular breathing and complex nasal tract also shouldn’t consume coffee since it increases your breathing activity It might lead to hyperventilation. 
  • Suppose you have arrhythmias (irregular heartbeats). Caffeine accelerates your heart at a non-conventional rate. 
  • Pregnant and breastfeeding mothers should avoid it because it can pass through the placenta, disturbing your child’s sleeping pattern.  
  • People who are already dealing with sleeping problems shouldn’t further promote alertness. It can lead to insomnia and anxiety. 
  • If you have anxiety issues, limit your intake 

Who should drink it?

  • If you do not have any health issues, problems breathing, or heart problems, you’re not pregnant, have blood pressure issues or are on any medication that will interact with it in a negative manner you can have it in moderation.  

When does it become dangerous?

  • When you become tolerant to caffeine’s effects: After extreme consumption, your body soon starts to become immune to it. Tolerance results in wanting more and more to have the same effect. Soon, it leads to addiction and withdrawal symptoms. 
  • When you cannot sleep at night: Caffeine leads to alertness, but too much of it can disturb your sleeping pattern and in extreme cases, can lead to insomnia. 
  • When you notice withdrawal symptoms like restlessness, anxiety, depression, shakes, sleepiness/insomnia. 
  • The caffeine content in your blood reaches 15mg/liter is a red flag. This can be fatal.
  • Headache, dehydration, and increased body temperature are other red flags that you have had too much caffeine. 
  • Many psychological behaviors include confusion, and disturbed concentration due to drinking coffee that has extra chemicals put in it to enhance its flavor and aroma. 

If you notice that your coffee makes you feel any of these symptoms, contact your doctor and avoid it until you have spoken to him or her about your symptoms.


The big question to ask yourself is whether or not your caffeine effect is being hindered because of your genes, habits, or health conditions.

If it is due to your habits, you need to cut back on the amount you drink or drink a more potent brew like french press or try Robusta beans if you aren’t drinking enough.

Unfortunately, if you feel like it is due to your metabolism or receptors, there isn’t much you can do to fix this.

If you have medical conditions, you need to stay away from caffeine or any stimulants since you could have serious adverse side effects.

in other words, be smart, listen to your body, and when in doubt, feel free to reach out to your Doctor.