Caffeine and its effects: Can Kids Drink Coffee?

Caffeine and its effects

Caffeine and its effects are a very common source of concern in the current day. Through all of the hustle and bustle of the modern world, caffeine has proved itself useful for many people at one point or another in their life. It is the most widely used central nervous system stimulant in the world. As of 2015, approximately 75% of children age 5 or older consume caffeine on a daily basis in the United States. Many people might stop and picture a 5-year-old drinking coffee in the morning before getting on the kindergarten bus– but that’s not the case! Caffeine is added to all kinds of beverages including sodas, teas, sparkling waters, and energy drinks marketed towards the younger generations. How does caffeine affect the body?

Caffeine is a part of a majority of people’s daily routines, especially in the United States. We all know someone (or maybe we are that someone) that cannot be spoken to until they’ve had their coffee! Coffee is commonly referred to as liquid gold or liquid energy, but how does it work?

Caffeine acts on the nervous system as well as the cardiovascular, renal, and respiratory systems. It blocks the uptake of a substance called adenosine. This substance is what builds up causing us to feel tired. For some people, caffeine can increase alertness, stimulate wakefulness, provide a prolonged ability to sustain intellectual activity, and decrease reaction times by blocking the uptake of the adenosine. These are the effects that draw the consumer in, but what if you knew that these effects might only be fleeting and could potentially leave you with some very unfavorable feelings in the future?

Anxiety is a condition affecting approximately 40 million American adults and 4.4 million children aged 3-17. Adults with anxiety disorders have been shown to react negatively to caffeine due to its role in affecting the hypothalamic-pituitary-adrenal axis (HPA axis). This system of the body regulates things like stress hormones and blood pressure, which directly affect how someone is feeling. For someone with an anxiety disorder, this can induce feelings of panic and even a panic attack. Because it blocks the uptake of adenosine and alleviates feelings of being tired, it can cause detrimental issues related to sleep and rest for many people. That crash you might feel after it wears off? That happens due to the rush of the adenosine finally being able to bind to those receptors making you feel very tired very fast. Not everyone experiences this, but many people do.

Sleep is the body’s way of restoring and repairing. This is the way in which we re-charge and perform necessary metabolic functions, especially those that repair and detoxify.  When it comes to anxiety and related conditions such as depression, sleep hygiene is very important. When sleep is off, hormone production can also be dysregulated including the stress hormone cortisol. Caffeine’s stimulatory effects can disturb sleep hygiene making repairing, detoxification, revitalization, and hormone balance difficult for the body to regulate. When these functions and processes are not being performed optimally, this can show up as issues such as brain fog and trouble concentrating, poor detoxification, skin issues, disruptions within the microbiome, hormone dysregulation, weight gain, and more.

Consuming caffeine should be limited to the beginning of the day and an appropriate amount. The full effects of caffeine are typically felt within 1 hour of consumption and can be felt for up to 6 hours following consumption.  This is why it is very important to be mindful of your caffeine consumption in relation to your desired bedtime if you are having trouble falling or staying asleep.

General amounts of caffeine in common beverages:

An 8-ounce cup of coffee

95-200 mg
A 12-ounce can of cola 35-45 mg
An 8-ounce energy drink 70-100 mg
An 8oz cup of tea 14-60 mg


What is an appropriate amount of caffeine for the average person? The average person can consume up to 400mg per day of caffeine without any harmful side effects. Keep in mind that everyone is different and unique in their other environmental factors as well as their genetics. Children, those with heart conditions or heart disease, women who are pregnant or breastfeeding, those with chronic headaches or migraines, people with peptic ulcers or GERD, and those on certain stimulant medications and even some antibiotics should be very careful in regard to consuming caffeine.

Because children are smaller they are especially sensitive to caffeine compared to adults. Studies have shown that children are especially susceptible to the effects of caffeine in regard to immediate effects as well as how they might be affected as they get older. Because most children consume caffeine through the consumption of sugar-sweetened beverages such as sodas and teas, they are more likely to be overweight or obese into adolescence and adulthood when they consume these beverages on a regular basis. These beverages have empty calories, lack vitamins and minerals, cause inflammation from added sugars, colors, dyes, flavorings, and act as diuretics leading to increased urination and possible dehydration. It’s best for kids and adults alike to stick to water as their main beverage of choice!

What about genetics? The genetic component to how someone might process caffeine relates to what are called single nucleotide polymorphisms (SNPs). These polymorphisms are very common within human DNA. This means that single amino acids are altered in the DNA sequence. These SNPs can be beneficial in some ways, but also harmful depending on the SNP as well as other factors such as diet, lifestyle, stress, etc. The CYP1A2 gene plays a role in the body’s ability to process exogenous substances including aflatoxin B1, acetaminophen, and caffeine. Those who have an SNP in this gene might process caffeine at a much slower rate compared to the general population. This might look like someone feeling the effects of caffeine far beyond the general 6-hour window after consumption.

For those who have this SNP and do not know, this might manifest as anxiety, restlessness, trouble concentrating, insomnia, and other behavioral and psychological issues as well as physical ones. If you or someone you know is struggling with anxiety, sleep issues, trouble concentrating, trouble losing weight, or hormone imbalances consider eliminating caffeine from your diet to see how it might help.

Keep in mind that caffeine withdrawal might happen for those who regularly consume it on a regular basis. This might include headaches, drowsiness, irritability, nausea, and trouble concentrating. This typically improves as time goes on and resolves itself after a few days.

If you are looking to learn more about Caffeine and its effects on mental health or nutrition, call us at 201-488-6678!



ADAA. (2021, April 21). Facts & Statistics.

CDC. (2021, March 22). Anxiety and depression in children: Get the facts. Anxiety and depression in children: Get the facts

Institute of Medicine (US) Committee on Military Nutrition Research. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington (DC): National Academies Press (US); 2001. 2, Pharmacology of Caffeine. Available from:

Nemours. (2017, February 1). Caffeine. Nemours Kids Health.

O’Neill, C. E., Newsom, R. J., Stafford, J., Scott, T., Archuleta, S., Levis, S. C., Spencer, R. L., Campeau, S., & Bachtell, R. K. (2016). Adolescent caffeine consumption increases adulthood anxiety-related behavior and modifies neuroendocrine signaling. Psychoneuroendocrinology, 67, 40–50. National Library of Medicine. (2021, July 2). Caffeine: Medline Plus.

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