By: Marisol Mercado, BS, CSUN Dietetic Intern Cohort 2021-2022
We’ve all seen (or been in) those long lines in the early morning or mid-afternoon lunch break of people waiting for that tasty cup of Joe (or tea). It’s all worth it once the caffeine starts to kick in. We’re alert, energized, and ready to tackle the demands of the day!
Although daily consumption of caffeine may be safe in the general population within recommended doses, there are certain individuals for which caffeine intake should be monitored. Here we will briefly review the sources, recommended intakes, potential benefits, and contraindications of caffeine.
Sources of Caffeine
When we think of caffeine, we may be imagining those bright red coffee berries from a tropical region in South America. But in fact, over 60 plants contain caffeine!1 It can be found in their beans, fruits, or leaves.1 Caffeine is widely available in commercial foods and beverages including cocoa-containing products, energy drinks, coffee, soft drinks, and tea.1,2 Caffeine may also be found in other unexpected places in the retail setting such as in medications (e.g. to treat migraines or reduce pain); dental hygiene products (e.g. gum; mints; mouthwash); and beauty products that purport “age-defying” benefits.2
Recommended Intakes
Many of us enjoy foods and drinks that contain caffeine, and some of us may feel that we simply cannot live without it! But how much caffeine is too much? Research has shown that daily intakes less than 400mg of caffeine appear to be safe for consumption in the general population.2,3 It is estimated that the average US adult consumes around 180mg of caffeine daily, which is approximately the equivalent of two, eight-ounce cups of coffee.2 It is important to consider that there are populations that may be more vulnerable to the effects of caffeine than others and therefore, are advised to consume caffeine with caution.
One of those vulnerable populations is pregnant women.4 The American College of Obstetricians and Gynecologists (ACOG) recommends that pregnant women consume no more than 200mg of caffeine per day.5 This amount also seems to be safe for breastfeeding women.2
Children are another population vulnerable to the effects of caffeine. The amount of caffeine in one can of cola (i.e., 29mg caffeine) can have the same effect on a child that two cups of coffee (i.e., 180mg caffeine) has on an adult!2 The American Academy of Pediatrics advises against caffeine consumption for children less than 12 years of age and recommends intakes no greater than 100mg of caffeine (about two, 12oz cans of cola) daily for adolescents.6 Plain drinking water is still considered the healthiest beverage option for meeting individual hydration needs.7
Potential Benefits
Supplementing with caffeine is common among athletes due to its well-known performance and cognitive-enhancing effects that include reduced fatigue, increased endurance, decreased pain perception, and improved alertness and concentration.8,9 Now who wouldn’t want that? Caffeine achieves this effect by blocking a compound in our bodies responsible for making us feel drowsy and tired.8 Caffeine also increases the concentration of dopamine and adrenaline in the body.8 Dopamine boosts mood while adrenaline, the chemical responsible for the “flight or fight” response, improves alertness.8
Contraindications
As mentioned before, there are some individuals for whom caffeine may be contraindicated, such as those on oral contraceptives, those with liver conditions (e.g., cirrhosis), and those who consume 3.5 standard alcoholic drinks per day.1 This means no coffee to “cure” that next day hangover. Caffeine may also not be appropriate for individuals with anxiety as it may worsen symptoms.10 Additionally, at least 85 different drugs are known to interact with caffeine, some with potentially adverse effects2 such as elevated heart rate.1
The Bottom Line
Daily caffeine intake at recommended doses is safe in the healthy adult population. Individuals that are considered vulnerable populations, such as pregnant women and children should monitor their caffeine intake, as should individuals with certain preexisting medical conditions, or those taking medications that may negatively interact with caffeine. If you would like more information on how to safely incorporate caffeine into your diet, a registered dietitian (RD) from the Marilyn Magaram Center is available to help. Follow this link for information on nutritional counseling: https://www.csun.edu/marilyn-magaram-center/products-services
References
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Caffeine Consumption.” Pharmacological Reviews, vol. 70, no. 2, 2018, pp. 384–411,
https://doi.org/10.1124/pr.117.014407. - Temple JL, et al. “The Safety of Ingested Caffeine: A Comprehensive
Review.” Frontiers in Psychiatry, vol. 8, Frontiers Media S.A, 2017, pp. 80–80,
https://doi.org/10.3389/fpsyt.2017.00080. - Wikoff D, et al. “Systematic Review of the Potential Adverse Effects of Caffeine
Consumption in Healthy Adults, Pregnant Women, Adolescents, and Children.” Food
and Chemical Toxicology, vol. 109, no. Pt 1, Elsevier Ltd, 2017, pp. 585–648,
https://doi.org/10.1016/j.fct.2017.04.002. - Lyngsø J, et al. “Association Between Coffee or Caffeine Consumption and
Fecundity and Fertility: a Systematic Review and Dose-Response Meta-
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699–719, https://doi.org/10.2147/CLEP.S146496. - American College of Obstetricians and Gynecologists. (2020). How much coffee can I
drink while I’m pregnant? https://www.acog.org/womens-health/experts-and-stories/ask-
acog/how-much-coffee-can-i-drink-while-pregnant - American Academy of Child and Adolescent Psychiatry. (July 2020) Caffeine and
children. https://www.aacap.org/AACAP/Families_and_Youth/Facts_for_Families/FFF-
Guide/Caffeine_and_Children-131.aspx - Harvard Health Publishing. (15 May, 2022). How much water should you drink?
https://www.health.harvard.edu/staying-healthy/how-much-water-should-you-drink - Pickering C, & Kiely J. (2019). Are low doses of caffeine as ergogenic as higher doses?
A critical review highlighting the need for comparison with current best practice in
caffeine research. Nutrition (Burbank, Los Angeles County, Calif.), 67-68,
110535–110535. https://doi.org/10.1016/j.nut.2019.06.016 - Shabir A, Hooton A, Tallis J, & Higgins FM. (2018). The Influence of Caffeine
Expectancies on Sport, Exercise, and Cognitive Performance. Nutrients, 10(10), 1528–.
https://doi.org/10.3390/nu10101528 - Klevebrant L, and Frick A. “Effects of Caffeine on Anxiety and Panic Attacks
in Patients with Panic Disorder: A Systematic Review and Meta-Analysis.” General
Hospital Psychiatry, vol. 74, Elsevier Inc, 2022, pp. 22–31,
https://doi.org/10.1016/j.genhosppsych.2021.11.005.