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In the last decade, caffeine has risen to be one of the most consumed substances in the world. How have new studies shaped our understanding of caffeine and its effects on the body? What are the recommended, safe levels of consumption? We did the research so you don't have to.
Medical Disclaimer: The Vitallis Team is made of health and wellness enthusiasts, but currently no doctors. Consult a medical provider before taking any new supplements as situations vary. This article is for informational purposes only.
INTRODUCTION
Caffeine can be found almost anywhere nowadays: coffee, tea, pre-workout, Celsius, soda, and even chocolate. It boasts a whole suite of benefits for mental and physical performance. Given how accessible this molecular tool has become, it is a necessary part of most Americans' workday. As it becomes more prevalent, it is important to keep up with the latest research about its effects. We collected the most recent studies conducted on caffeine (not coffee) and its impact on the body.
CONTENT
Caffeine's Origins
General Information
Caffeine Benefits
Dosage Concerns
Caffeine Effects During and After Pregnancy
Fetal Development
Caffeine in Breastmilk
Caffeine's Association with Anxiety
Caffeine and Flow States
Physical Performance Benefits
Conclusion
Caffeine's Origins
Caffeine is a chemical stimulant found in various plants including teas, coffee beans, cacao, and yerba mate. In ancient times, people discovered that distilling these plants into beverages allowed them to extract the beneficial properties of caffeine we all know and love. It started as a medicinal remedy, but around the 15th-16th century it became extremely popular in Europe. Since then it has only grown in popularity for its stimulating effects and its role in social interaction. Now, more than 80% of adults consume caffeine daily.
General Information
Caffeine is a stimulant found not only in coffee and tea but as an additive in +100 different sodas, energy drinks, and pre-workouts. It has many researched, positive effects on physical and mental performance. It is generally considered to be a safe tool for increasing alertness and productivity.
It can have some detrimental effects on sleep, but only if consumed within 8 hours of going to bed. While it does impact the dopamine system, it is generally not considered as an addictive substance. Under recommended dosages, users experience no withdrawal; with elevated use there is only mild irritability and headaches.
Caffeine Benefits
Caffeine has several potent impacts on both the brain and body functions. It blocks adenosine receptors which are the reason you feel tired after a long day awake; this is why caffeine gets rid of the pesky morning grogginess. It increases focus and motivation by stimulating the release of dopamine and acetylcholines. Caffeine has widespread benefits in athletic performance from faster reaction times to strength performance. It has mental benefits that increase memory, mental agility, and critical thinking.
Dosage Concerns
The average dose of caffeine is 80-100mg in a cup of coffee; as energy drinks become more popular, they drive up the average intake to 200-300mg per serving. Even a can of soda can have up to 50mg of caffeine. These higher serving dosages could be having more serious long-term effects on individuals. The recommended concentrations of caffeine are between 1-3 mg per kg of body weight with a cap around 400mg.
Kilograms | 45 | 57 | 68 | 80 | 90 |
Lbs | 100 | 125 | 150 | 175 | 200+ |
Caffeine | 45-135 mg | 57-170 mg | 70-200 mg | 80-240 mg | 90-270 mg |
In a survey conducted in 2012, "children and adolescents consumed 35 mg/day caffeine, whereas adults consumed an average of 173 mg/day. Average intake was 196 mg/day for men and 151 mg/day for women". New market trends with increased coffee consumption, stronger energy drinks, and prevalence of caffeine in sodas, suggest that the average adults consumes +250 mg daily.
This increase in consumption is concerning because many of the negative effects associated with caffeine are magnified at higher dosages.
Caffeine Effects During and After Pregnancy
Some of the newest studies focused on the potential effects of mother ingesting caffeine during and after pregnancy. While there is no research to support a correlation, many people believe the increased caffeine use may contribute to rising ADHD diagnoses.
Fetal Development
In a study from 2023, it was concluded that caffeine intake during pregnancy increased fetal breathing and heart rate. There was a correlation between routine caffeine intake and lower birth weights. Overall, it was theorized that high doses of caffeine increases stress in fetal development.
Caffeine in Breastmilk
A study done by LactMed® in 2024 found that, "fussiness, jitteriness and poor sleep patterns have been reported in the infants of mothers with very high caffeine intakes". This lead to the discovery that caffeine can be found in breast milk directly after maternal ingestion. While the concentration is not alarmingly high, it could raise concerns for extremely young infants. With the average 6 month old being only 17 lbs, its 'recommended' safe dosage would be 7-20mg. While more studies would be needed to gather conclusive evidence, there was a correlation between maternal caffeine ingestion, weight gain in infants, and cases of iron-deficiency.
Caffeine's Association with Anxiety
It is well established that high doses of caffeine are related to increased levels of anxiety. Additionally, new studies are showing this prevalence in both adolescents and medical students internationally. The surveys showed a very direct correlation between caffeine intake and reported levels of anxiety. This occurred in individuals regardless of their predisposition to anxiety.
Additionally, it was observed that, "there was a dose-dependent relationship between the prevalence of anxiety and high-caffeine drinks". These 2024 studies confirm previous findings and add to the portfolio of evidence showing the negative effect of routine overuse of caffeine. It is important to learn what beverages contain caffeine and monitor your intake to avoid overuse.
Caffeine and Flow States
The "flow state" is a term referring to a motivated neural state where mental and physical tasks just feel easy. The activity is intrinsically rewarding and you feel incredibly focused on the task at hand. Caffeine may be a useful tool for intentionally achieving these states of incredibly heightened focus and performance. It increases the release of dopamine and acetylcholine; both of which are neurotransmitters that heighten intrinsic motivation.
While caffeine is not guaranteed to induce a flow state, it acts as a catalyst for our brain to be in a prime condition for a flow. It can be reasonably decided that with clear goals, caffeine, and some practice blocking out distractions, anyone can learn how to consistently move into a flow state. This priming has actually been measured. In a literature review conducted by Reich, electroencephalogram (EEG) results showed an increased presence of theta band waves in the frontal cortex which are associated with focus and increased neural connectivity. This suggests that caffeine is a critical agent in setting up a flow-positive environment in the mind and body.
Misconceptions Around Caffeine
There are many reported effects of caffeine that appear to be merely anecdotal or not reflective of the greater population as a whole. All of these conclusions are based on the mean caffeine intake ~180mg.
Dehydration
Caffeine does not directly act as a dehydrating agent. However, it should be considered that drinking caffeinated beverages as not hydrating. Drinking a caffeinated beverage may reduce your intake of water and electrolytes which can give the appearance that caffeine causes dehydration.
Weight Loss and Metabolism
Several studies found a correlation between caffeine intake and the metabolization of fat. However, long-term studies were flawed with several potentially confounding variable including: diet, exercise intensity, and caffeine habituation. In general, caffeine is known to make exercise more potent, rewarding and habitual. In this sense, it could be used to help weight loss by increasing daily exercise.
Depression
In studies conducted as recently as 2022, caffeine was found to have an inverse correlation with subjective depression. Individuals who used caffeine daily <400mg were found to have less depressive symptoms. This is likely related to caffeine's stimulation of dopamine and serotonin which are factors in mood and motivation. However, it is also important that there are two scenarios where caffeine heightened depressive symptoms. First, in individuals with routine overuse, there were higher levels of anxiety and discontent. Second, individuals who routinely used caffeine too close to sleep experience depressive symptoms originating from sleep deprivation.
Lethality
It has been projected that a lethal dosage of caffeine would be around 5000 mg or 5g; this makes it extremely unlikely to overdose on caffeine. However, due to its stimulant effects, it can increase the risk for other lethal conditions in some predisposed individuals.
Gender Specific Effects
While there is scattered data citing differences in the effect of caffeine between biological males and females, it was concluded that the differences were likely due to either hormonal variations (birth control) or merely differences in the mean weight of participants. There are an equal number of studies showing no difference in the effects making it largely inconclusive.
Osteoporosis
Moderate caffeine use has not been shown to be a contributing factor in the development of osteoporosis. This is especially true if you are maintaining a balanced diet with an intake of calcium.
CONCLUSION
As caffeine continues to grow in prevalence, more and more research will be developed to better define and understand its effects. It is important to stay up to date and make sure that your own use habits do not cause detrimental health effects. Caffeine is a powerful stimulant that can be used to enhance motivation and performance. It is also a reinforcing agent that can help develop good habits.
If you have any question or feedback, feel free to leave a comment or message us.
If you are interested in how you can maximize the benefit of your daily caffeine intake, read out article on caffeine routines here.
Check out our other most recent content on health and wellness practices here.
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