Caffeine is a central nervous system stimulant that is found naturally in some plant seeds, nuts, and leaves that affects the human body in numerous ways [1, 2]. People consume it on a daily basis to combat fatigue and for physical mental energy [3, 4]. Caffeine is a diuretic and increases urination . Since it is also a drug, it carries its own risk like other drugs and affects each individual differently based on age, health, the amount is taken, whether the person used to take it, and whether other drugs are taken around the same time .
Caffeinated beverages include tea, coffee, energy drinks, soft drinks, sports drinks, and cocoa beverages that contain caffeine as the main ingredient along with some other compounds such as sugars and sweeteners, electrolytes, preservatives, and acids . The European Food safety authority (EFSA) recommends 400mg per day from all caffeine sources and single dose of 200mg to be safe for adults in the general population, which is roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two energy shot drinks [6, 7]. For children and pregnant women, World health organization (WHO) recommends less than 300mg per day [6, 8].
In the Pacific region, caffeine consumption of tea and soda by the general population has been significantly increased over the last decade [9, 10]. As proven on a global scale, caffeinated drinks have in the last ten (10) years outshot and account for about 20% of the total sale among the beverage industry . Intake of caffeine does have various health effects on adults, children, pregnant women, and students . The effects range from moderate such as increased alertness and concentration to severe that can be toxic to the body .
It was identified that the average amount of each caffeine beverage in the pacific region is; the red bull is 32mg/100mls, mountain dew 15mg/100, coca-cola 9.7mg/100, diet coke 9.7mg/100ml, brewed black tea 22.5mg/100ml, and coffee mixed beverages is from 20mg-194mg per 100ml . Ninety-Eight percent (98%) of caffeine consumed comes from these beverages . A report by Knowledge-Based value research (kbvresearch) shows Asia pacific caffeinated beverages market to grow at a compound annual growth rate (CAGR) of 8.3% during the years 2019-2025 . The market produces and supplies beverages mainly coffee, carbonated soft drinks, and tea to the rest of the pacific region.  This increase is largely attributed to the lifestyle changes of rapid urbanization, such as income levels, small family, busy lifestyle, shift from traditional pacific culture to western culture, and most importantly a shift from rural to urban areas has driven the demand for easy to cook foods and drinks [5, 12].
However, the amount consumed per individual is dependent on age and various reasons with its health impacts vary on the amount taken .
The main effects of caffeine consumption are the intake of moderate caffeine that is associated with cognitive function improvements such as increasing attention, memory, reaction time, wakefulness, and concentration [1,3]. Intake of caffeine on the other hand alters the sleeping pattern thus decreasing sleep duration as well as sleep quality of an individual . Other symptoms include excitability, anxiety, irritability, dehydration, and the need to urine more often . The effects can be experienced between 5 to 30 minutes and may continue up to 12 hours after consuming caffeine .
However, consumption of caffeine over 400 mg/ day for adults and over 300 mg/day for children and pregnant women can be harmful, causing caffeine toxicity . It has been reported that the increase in the caffeine intake by adults showed a significant twice as high risk than moderate caffeine intake.
Restlessness dizziness, dehydration, need to urine more often, high body temperature, faster breathing and heart rate, headache, lack of concentration, and stomach pains are its main health effects [1, 13].
A systematic review by Doepker, Franke, and Wikoff confirms that pregnant women consume caffeine and this can lead to pregnancy complications . Another study by Kaiser permanent division of research shows strong evidence to date linking the high doses of caffeine intake during pregnancy to miscarriage .
Furthermore, in younger children bone strengthening is crucial in childhood, however, too much caffeine can interfere with calcium absorption, which negatively affects proper growth [1, 3]. Children who drink high-calorie specialty coffees tend to have weight gain and suffer from sleep problems and anxiety . Caffeine poison in small children is possible if a lower amount such as 1g of caffeine which is equal to around 12 energy drinks is consumed one after the other [1, 13].
Students also take caffeine to continue working or staying up at night studying. A study done in New Zealand shows that Caffeine is used by approximately 92% of college students, 65% using caffeine on a daily basis, with an average of 159 to 849.86 mg caffeine consumed per day . During times of increased academic stress, 63% of college students have reported an increase in their caffeine intake. . The effects of consuming caffeine are headaches, spells of terror panic, feeling trapped or caught, worrying too much about things, and having a feeling of worthlessness. The research also shows students with caffeine intake of 400mg/day or more showed a significant twice as high risk for these symptoms.
Large amounts of caffeine can lead to overdose . The following symptoms of tremors, nausea and vomiting, very fast and irregular heart rate, panic attacks, and seizures are symptoms of an overdose of caffeinated related beverages . Though it is possible to die from consuming caffeine, the chances are exactly extremely rare . This would usually happen if 5-10g of caffeine (or 80 cups of strong coffee is consumed consecutively . However, a regular heavy dose of caffeine (more than 4 cups of coffee per day) may lead to long term effects like difficulty sleeping, seizures, confusion, dizziness and ringing in the ears, muscle tremor, poor appetite, frequent urination, and low blood pressure with faintness or falls [1, 5].
Caffeine used with alcohol poses an enormous strain on the body and can mask some alcohol effects such as falling asleep, leading to drinking more, and risk taking behavior [1, 5]. Hence, taking other stimulant drugs with caffeine can increase the risk of cardiovascular problems [1, 5]. Since caffeine is a drug, giving up taking it after a long time can be challenging, because the body has to get used to functioning without it [1, 5]. This results in withdrawal symptoms that start within 24 hours and continue up to 36 hours. The symptoms include flu, headache, dysphoric, difficulty concentrating, and marked fatigue or drowsiness .
Serious health effects of caffeine can be prevented in households as well as on national and global levels. There are certainly high energy foods that can be taken to boost energy while maintaining a good mood . An article by Shiel on MedicineNet recommended taking natural foods such as smart cards, cashews, almonds and hazelnuts, brazil nuts, lean meats, salmon, leafy greens, fiber, water, and fresh produce . It is also advised to always have breakfast in the mornings, frequent meals, and engage in sports . All of these, contribute to steady blood sugar levels which stimulate the secretion of substances that positively affect mood and decrease the need for consuming more caffeine beverages .
On a global level, WHO has set guidelines recommending lower (less than 300gm per day) caffeine consumption in pregnant women to reduce the risk of pregnancy loss and low birth weight neonates. . EFSA also published their scientific opinion on the safety of caffeine, advising that “caffeine intakes from all sources up to 400mg per day and single doses of 200mg do not raise safety concerns in adult population but a single dose of 100mg may increase sleep latency and reduce sleep duration in adults particularly close to bedtime” . EFSA recommends the intakes of pregnant or lactating women should be decreased to 200mg per day from all sources of caffeine” .
However, there are no discussed guidelines at the national level in the pacific countries for the potential diuretic effects of caffeine with this recent increase in caffeine consumption . Fiji is the only pacific country that has potential diuretic effects of caffeine guidelines discussed in its country which stated that “heavy tea and coffee consumers may need to adjust their water intake” [6, 11]. Increased awareness of the negative effects of caffeine beverages in pacific countries is essential for individual choice of caffeine intake .
In conclusion, caffeinated beverages sales and consumption has significantly increased over the last decade and is expected to continue in the pacific region. These can pose health effects on each population group, especially the adults, children, pregnant or lactating women, and students. Preventive measures of taking natural healthy foods instead of caffeinated beverages increased awareness on the negative effects and standard set guidelines of caffeine intake in pacific countries must be implemented to avoid any serious health effects of caffeine intake.
1. Caffeine - Alcohol and Drug Foundation. Retrieved: https://adf.org.au/drug-facts/caffeine/. [Cited 2020 October 31]
2. Definition of Caffeine. Retrieved: https://www.medicinenet.com/energy_foods_pictures_slideshow/article.htm. [Cited 2020 October 31]
3. The Effects of Caffeine on Your Body. Retrieved: https://www.healthline.com/health/caffeine- effects-on-body#Reproductive-system. [Cited 2020 October 30]
4. Caffeine: Benefits, risks, and effects. Retrieved: https://www.medicalnewstoday.com/articles/285194#takeaway. [Cited 2020 October 30]
5. Rowe Karlie. Caffeine intake, influences and experiences: the development of caffCo-a New Zealand caffeine consumption habits questionnaire. Massey University, Albany. 2015; 1-153.
6. Guidelines on caffeine intake - Coffee and Health. Retrieved: https://www.coffeeandhealth.org/topic-overview/guidelines-on-caffeine-intake/. [Cited 2020 October 31]
7. Caffeine: How much is too much? - Mayo Clinic. Retrieved: https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in- depth/caffeine/art-20045678. [Cited 2020 October 31]
8. WHO recommendation on caffeine intake during pregnancy | RHL. Retrieved: https://extranet.who.int/rhl/topics/preconception-pregnancy-childbirth-and-postpartum- care/antenatal-care/who-recommendation-caffeine-intake-during-pregnancy. [Cited 2020 October 31]
9. Mehta, S.A; Pokale, A; Karmarkar. (2018) Is caffeine consumption amongst students on the rise? Comparison between medical and engineering students: a pilot study. International Journak of community Medicine and Public Health. 2018; 5 (11):4783. Doi: 10.182303/2394- 6040.ijcmph20184569. [Pubmed]
10. Caffeine in the Diet: Country-Level Consumption and Guidelines. Retrieved: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266969/. [Cited 2020 October 31]
11. Antioxidant and Neuroprotective Effects of Caffeine against Alzheimer's and Parkinson's Disease: Insight into the Role of Nrf-2 and A2AR Signaling | Request PDF. Retrieved: https://www.researchgate.net/publication/344393093_Antioxidant_and_Neuroprotective_Effe cts_of_Caffeine_against_Alzheimer's_and_Parkinson's_Disease_Insight_into_the_Role_of_Nrf- 2_and_A2AR_Signaling. [Cited 2020 October 30]
12. Asia Pacific Caffeinated Beverage Market (2019-2025). Retrieved: https://www.researchandmarkets.com/reports/4871755/asia-pacific-caffeinated-beverage- market-2019. 2019 [Cited 2020 October 31]
13. Key Findings and Implications of a Recent Systematic Review of the Potential Adverse Effects of Caffeine Consumption in Healthy Adults, Pregnant Women, Adolescents, and Children. Retrieved: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6212940/. [Cited 2020 October 30]
14. Caffeine is linked to miscarriage risk, new study shows. Retrieved: https://www.sciencedaily.com/releases/2008/01/080121080402.htm. [Cited 2020 October 30]