Caffeine Safe Limits: How to Determine Your Safe Daily Dose
A safe caffeine limit is the amount of caffeine a person can consume without experiencing any negative caffeine overdose symptoms.
Unfortunately, it’s hard to assign an exact amount for everyone because people can have different sensitivities or reactions to caffeine based on age, medical history, and tolerance.
In this caffeine safe limit guide, we’ll attempt to break down what is generally considered a safe daily amount of caffeine for most major categories of people considering age, health history, and experience with caffeinated products.
Caffeine Amounts for Healthy Adults
For healthy adults with no medical issues, it is generally agreed upon that 300mg-400mg of caffeine can be consumed daily without any adverse effects.¹
This is equivalent to about:
- 5.2 Shots of espresso
- Two 5 Hour Energy Shots
- 1 Starbucks Venti brewed coffee
- 2.5 16 fl.oz. Monster Energy Drinks
- 5 8 fl.oz. Red Bulls
- 11.7 12 fl.oz. Cokes
Safe Limits for Children
Because children’s brains are continuing to develop and their bodies are still growing, limited caffeine is recommended.
A recent study from The University Children’s Hospital in Zurich, Switzerland showed the importance of sleep for a child’s developing brain. Caffeine can interfere with sleep, therefore, possibly hindering proper brain development.
Ages 12 and Under
Caffeine isn’t recommended for children under 12. Occasionally, some doctors may recommend caffeine for children diagnosed with ADHD, but generally there really is no reason for children under 12 to consume caffeine.
For children 4 or older an occasional caffeinated soda or chocolate treat will likely pose no concern and around 45mg per day¹ is recognized as a safe amount, but caffeine shouldn’t be a daily part of a child’s diet.
While greatly limiting caffeine to this age group would be ideal, because of the increasing demands placed on teenagers in regards to school, sports, and even work; caffeine consumption is becoming more common with this age group.
Developing teens should have no more than 100mg of caffeine daily² due to the importance of sleep, brain development, inexperience with caffeine, and possibly unknown medical conditions.
This is equivalent to about:
- 1.3 Shots of espresso
- 1.25 8 fl.oz. Red Bulls
- .5 of a 5 Hour Energy Shot
- .6 of a 16 fl.oz. can of Monster Energy Drink
- .2 of a Starbucks Venti brewed coffee
- 3 12 fl.oz. Cokes
Caffeine for Those with Health Concerns
Adults as well as children with either diagnosed or undiagnosed medical conditions can have adverse health implications with even small amounts of caffeine.
Because caffeine is a stimulant, it increases heart rate as well as blood pressure. Therefore, those with heart arrhythmias³, murmurs, and hypertension should limit their caffeine intake.
It’s important to note that caffeine hasn’t been proven to cause arrhythmias, heart disease or other heart related problems.¹
Those with pre-existing arrhythmias, murmurs, and hypertension should limit caffeine to no more than 200mg daily and are advised to consult their physician before consuming caffeine.
Type 2 Diabetes
The majority of the research shows that caffeine doesn’t increase the risk of someone developing type 2 diabetes, but actually decreases risk.¹
However, those already diagnosed with type 2 diabetes should limit caffeine consumption because it can impair glucose metabolism in diabetics.4
Those with type 2 diabetes should restrict their consumption to around 200mg daily or follow their doctor’s instructions concerning caffeine intake.
Pregnant or Nursing Women
We have covered pregnancy and caffeine extensively in our article located here.
In summary, we concluded that mothers consuming 200mg of caffeine or less a day results in very little risk for the developing fetus and nursing infant.
200mg of caffeine is equivalent to about:
- 2.6 shots of espresso
- 2.5 8 fl.oz. Red Bulls
- One 5 Hour Energy Shot
- .5 of a Starbucks Venti Brewed Coffee
- 1.25 16 fl.oz. Monster energy drinks
- 6 12 fl.oz. Cokes
Those Ultra-Sensitive to Caffeine
For those ultra-sensitive to caffeine it is hard to determine an exact caffeine safe limit. Some people can have one cup of coffee (100mg-120mg) in the morning and still fail to get to sleep that evening. This is well after the caffeine’s effects should have worn off as it does for “normal” caffeine consumers.
If the ultra-sensitive choose to consume caffeine they should do so in small amounts until they find the amount that works, but doesn’t cause unwanted side-effects.
We suggest that these people start with 50mg of caffeine daily and then slightly increase or decrease their consumption from there.
This is equivalent to about:
- 1.5 12 fl.oz. Cokes
- 1 4 fl.oz. brewed coffee. (not Starbucks)
- 1 8 fl.oz. strong black tea
A General Guide to Caffeine Consumption Only
Our caffeine safe limit amounts listed above are based on what the latest research tells us and should be used as a general guide, not the “gospel’.
There are just too many variations in the human population to determine a safe limit for caffeine use in ALL people.
Caffeine should be treated as any other drug and used with caution until a person understands how it interacts with his/her particular genetic make-up and health profile.
It’s also important to understand that a person’s safe limit of caffeine can change over time as a person’s health evolves over his/her lifetime.
1. Heckman, M. A., Weil, J. and De Mejia, E. G. (2010), Caffeine (1, 3, 7-trimethylxanthine) in Foods: A Comprehensive Review on Consumption, Functionality, Safety, and Regulatory Matters. Journal of Food Science, 75: R77–R87. doi: 10.1111/j.1750-3841.2010.01561.x Link