Journal of Nutrition and Human Health

All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.
Reach Us +1 (629)348-3199

Review Article - Journal of Nutrition and Human Health (2023) Volume 7, Issue 1

Would ′′ Low Caffeine Intake′′ rather than ′′ No caffeine intake′′ assures Healthy Human Body

Tabinda Sattar*

Institute of Chemical Sciences, Bahaudin Zakaraya University Multan, Pakistan

Corresponding Author:
Tabinda Sattar
PhD Scholar, Institute of Chemical Sciences
Bahaudin Zakaraya University Multan, Pakistan
E-mail id: parsamariam22@gmail.com

Received: 05-Feb-2023, Manuscript No. AAJNHH-23-89395; Editor assigned: 08-Feb-2023, Pre QC No. AAJNHH-23-89395(PQ); Reviewed: 22-Feb-2023, QC No. AAJNHH-23-89395; Revised: 24-Feb-2023, Manuscript No. AAJNHH-23-89395(R); Published: 28- Feb -2023, DOI: 10.35841/aajnhh-7.1.135

Citation: Sattar T. Would “Low Caffeine Intake” rather than “No caffeine intake” assures Healthy Human Body. J Nutr Hum Health. 2023;7(1):135

Visit for more related articles at Journal of Nutrition and Human Health

Abstract

Background: Caffeine consumption is now common worldwide, due to its wide benefits. Caffeine intakes would affect the three major systems like mental, cardiovascular and reproductive ones. Aims: This review focuses on the point that caffeine prohibition will make you unable from enjoying the unlimited caffeine benefits. Methods: When the caffeine intake amounts exceed about 300 mg/day, then some adverse effects may be resulted. Results: Although stamina to consume caffeine vary from person to person and is gender specific also. But low to moderate caffeine intakes ((?40 mg to ?300 mg/day) have been reported for the positive effect on overall human body resulting in alertness, vigilance, complex decision making, cognition, attention improve, muscle strength, endurance, improved cardiac and sexual health. Conclusions: So in order to fully benefit from it you need to be vigilant about the caffeine amounts of the caffeinated products you are taking and also your body capacity of caffeine consumption.

Keywords

Caffeine consumption, Caffeine benefits, Caffeine intakes, Caffeine doses, Caffeine sources.

Introduction

The widely used central nervous system stimulant and psychoactive drug is not other than the caffeine. Different parts of world differ in the usage of caffeine although it is legal and unregulated [1]. Chemically related to adenine and guanine bases, it is very bitter in taste. Seeds, nuts and leaves of some plants found in Africa, East Asia and South America are the main sources of caffeine. Although many artificial sources of caffeine are present which are widely used worldwide? [2]

The main function of caffeine is the improved body performance by relief from conditions of drowsiness and sleepiness. The chemistry behind the mechanism of action of caffeine lies in the fact that the caffeine can reversibly blocks the adenosine receptors that creates the drowsiness conditions after long wakeful hours [3]. Caffeine can affect the overall human health. Caffeine intakes in moderate and low amounts can cause increase in alertness, energy and cognitive functions. But excessive amounts of caffeine have been reported not only creating some psychological effects (e.g., changes in motivation, determination, belief, mood states, etc.) but cardiovascular and sexual effects as well.

For most healthy adults, the safe amount of caffeine for most healthy adults is up to 400 milligrams (mg) per day. Although the same amount of caffeine may be too much for children. So there are no hard and fast rules for the standard bearable amounts of caffeine although all the humans using caffeinated products should be aware of the amounts of caffeine present in that specific caffeinated products under their regular use. On the whole all persons may use caffeinated food products and fully enjoy its benefits but should avoid too much use of these on regular basis [4].

As the amount of caffeine varies widely among different food products of the same type for instance the coffee variety of different kinds may contain different caffeine amounts [5]. So a person should be well aware off the amounts of caffeine present in the caffeinated products under regular use. (Table 1) describes the highest and lowest amounts of caffeine present in coffee, energy drinks and other caffeinated food products. If a person wants to avoid any unpleasant side effects of caffeine then he or she should choose the coffee or energy drink having less caffeine rather than having highest caffeine as too much of caffeine is harmful for all age groups and genders as well [6].

  Coffee All 8Oz 2-200
 
1 Highest Caffeinated Starbucks Blonde, Roasted Coffee Vent, 20Oz 475
  Coffe
  Lowest Caffeinated Coffee Brewed, Decaf 8Oz 02-May
  Tea All 8Oz 0-95
2 Highest caffeinated Tea Starbuck Latte Chai 8Oz 47
  Lowest Caffeinated Tea Herbal Tea 8Oz 0
  Soft Drink All 8Oz 0-60
3 Highest Caffeinated Soft Drink Pepsi Zero Sugar 20Oz 115
  Lowest Caffeinated Soft Drink 7Up, Fanta, Sprite 20Oz 0
  Energy Drinks All 8Oz 50-200
4 Highest Caffeinated Energy Drink Bang Energy 16Oz 351
  Lowest Caffeinated Energy Drink Starbuck Refresher Can 12Oz 50
  Caffeinated Snack Food All 36g 20-150
5 Highest Caffeinated Snack Food Steam Caffeinated Peanut Butter 36g 150
  Lowest Caffeinated Snack Food GU Energy Chews(Strawberry/Black berry) 4Chews 20
  Ice Cream &Yougurt   40Oz 1-125
6 Highest Caffeinated Snack Food Bang (Caffeinated Icecream) 40Oz 125
  Lowest Caffeinated Snack Food Haagen Dazs Chocholate Icecream 40Oz Less than 1
  Chocolate Candy & Chocolate Drink All 1 Box 2-600
7 Highest caffeinated Snack Food Crackheads Gourmet Chocholate-Coffee 1 Box 600
  Lowest Caffeinated Snack Food Hershey’s Chocholate Low Fate Milk 12Oz 2
  Over the Counter Pills All 2 Tablets 65-300
8 Highest Caffeintaed Snack Food Zantex-3-Weight Loss Supplement 2 Capsules 300
  Lowest Caffeinated Snack Food Anacin 2 Tablets 83
  Pure Caffeine All 1 tsp 70-200
9 Highest Caffeinated Caffeine Powder 1/16 or 1/32 tsp 200
  Lowest Caffeinated Liquid Caffeine (Brand) 1tsp 83

Table 1. Major Food Items having Relevant Caffeine Amounts.

Despite of the empirical facts that high levels of caffeine are harmful in children and adolescents too, many parents still remain unconscious with the caffeine intakes of their children and themselves as well. Nevertheless the caffeine intakes are safe in adults but adults should also be well aware off the caffeine contents of the caffeine present in the caffeinated food products [7]. In developed countries like United Estates America, caffeine consumption in children and adults should be according to the recommendations of the American Academy of Pediatrics. As mostly parents are not aware off the caffeine intakes of their children and there is no record of the routine address at the pediatric appointments so caffeine consumption in USA is producing irrelevant records about highest caffeine damages [8].

Caffeine use is different at different country levels. (Table 2) describes the highest caffeine users throughout this world. Although Finland is considered as the highest coffee consumer but overall caffeine is most highly used in Sweden [9]. In spite of the beneficial effects of caffeine, the severe kinds of harmful effects of caffeine usage also reported from the highest caffeine consumer in the world that is none other than Sweden. From these preliminary reports, it can be well considered that caffeine remains a friend for human body until and unless it is used in moderate amounts, but it may be proved as foe if high doses used on regular basis [10].

Number
/Country
Highest Coffee Consumers
(Kg)
Highest Tea Consumers
(lbs)
Highest Soft Drink Consumers Highest Chocolate Drink Consumers(Pounds) Highest  Total Caffeine Consumers (mg/Day)
1 Finland (12) Turkey(3.16) Argentina(155) Switzerland(18.1) Sweden(388)
2 Norway(9.9) Ireland(2.19) United States America(154) Germany(16.3) Norway(379)
  Iceland(9.0) United Kingdom(1.94) Chile(141) Austria(15.7) Netherland(369)
4 Denmark(8.7) Iran(1.50) Mexico(137) Ireland(14.6) Denmark(354)
5 Netherland(8.4) Russia(1.38) Uruguay(113) United Kingdom(15.1) Finland(322)
6 Sweden(8.2) Morocco(1.22) Belgium(109) Norway(13) Germany(292)
7 Switzeland(7.9) Newzealand(1.19) Germany(98) Estonia(12) Switzerland (275)
8 Belgium(6.8) Egypt(1.01) Norway(98) Sweden(11) Austria (276)
9 Luxembuy(6.5) Poland(1.00) Saudi Arabia(89) Kazhaghstan(10.9) Nicerogue (219)
10 Canada(6.2) Japan(0.99) Bolavia(89) Slovakia(10.7) France(215)

Table 2. List of Top 10 Highest Caffeine Consuming Countries.

What would caffeine do with human body

Blood- brain barrier that separates the blood stream from brain is rapidly crossed by the caffeine that is both water and lipid soluble. When inside the brain, caffeine rapidly reduces the effects of adenosine. Caffeine will act as non selective and competitive antagonist of adenosine receptors as its structure is quite similar to that of adenosine receptors [11]. Caffeine is also an antagonist of inositol trisphosphate receptor 1 and iontoropic glycine receptors (. It can also act as a voltage dependent activator of the cyanodine receptors (RYR1, RYR2, and RYR3).

No direct binding of caffeine and dopamine receptors is still reported. But it can subsequently affect the binding activity of dopamine at its receptors specifically A1-D1 receptors (heterodimine) and A2A-D2 receptors (heterotetramine). Caffeine can mediate the psychostimulant effects and pharmacodynamic interactions of A2A-D2 to the point dopaminergic psycho stimulant. The release of dopamine in the dorsal striatum and nucleus accumbens core is the main responsibility of caffeine use. Caffeine plays a role in the raising intracellular CAMP, activates proteins kinase A TNFalpha and leukotriene synthesis [12].

Caffeine can inhibit TNF-alpha, leukotriene synthesis that will reduce the inflammation and innate immunity [13]. It also affects the cholinergic system where it inhibits the enzymes. The main wakefulness prompting effects of caffeine are resulted by disinhibition of tuberomammily nucleus. In the ventrolateral preoptic area (VLPO) adenosine A2A receptors are antagonized by caffeine. Only 45 minutes are sufficient for caffeine to get absorbed by small intestine and thus instantly distributed to the bodily tissues [14].

The half life of caffeine is different among different individuals according to pregnancy, other drugs, liver enzyme function and age [15]. Among healthy individuals the total time required for body to eliminate one-half of caffeine doze is 3-7 hours. In pregnant women during third trimester it will be 15 hours, while oral contraceptives it may be 14 hours and decrease to 30-50% due to smoking. In new born this time would be 80 hours [16]. After using fluroxamine-antidepressant (4.9 hours increase to 56 hours). Cytochrome P450 oxidase can metabolize the caffeine in liver. Parazanthine (84%), theobromine (12%), theophylline (4%) and 1,3,7-trimethyl acid (minor quantity). These will increase free fatty acid level, urine volume, relaxes smooth muscles and dilates blood vessels collectively [17,18].

The caffeine intakes will be proved very much beneficial if taken in moderate amounts. When inside human body, caffeine affects three major systems like mental, cardiovascular and sexual ones. The main effect of caffeine can be recognized as the central nervous system stimulant. It can give temporarily relieve from drowsiness and fatigue. Also its stimulating effect can produce alertness in right way. A research report has revealed that a 45 percent low risk of suicide has been detected in those participants who were taking caffeine in regular and moderate amounts. Caffeine intake in high amounts may cause confusion and headaches [19].

Gender differences are related with effects of the caffeine intakes. Male cardiac and reproductive systems are not much affected by high caffeine intakes. Whereas the high caffeine intake may create some issues with pregnancy in case of females. Heartburn, nausea and vomiting are some symptoms of high caffeine intakes. Irritability and muscle aches may be some symptoms of caffeine withdrawal. The present study is related to the effects of caffeine intakes on human body [20].

Mental effects of caffeine

Mental effects of caffeine are nevertheless much important. Different doses of caffeine have different mental effects. Although low to moderate values can improve cognitive function and high doses may lead towards cognitive failures. Neuromodulating and homeostatic effects of caffeine acts on two receptors with contrasting actions. The A1 and A2A receptor antagonism of caffeine will influence the optimal levels of adenosinergic activity [20]. The authors reported that different doses of caffeine impact differently upon mental conditions.

Anxiety, jitters and nervousness are the main results of high caffeine intakes. While low caffeine intakes will surely give soothing effects to mental health of humans. Daytime sleepiness in adolescents may be caused by high doses of caffeine [21]. So high caffeine intakes on regular basis would have negative impact upon the human health. As caffeine has become the most used psychoactive drug worldwide during the last decade [22]. The dopaminergic activity including mood, attention, executive functioning, and regulation of behavioral traits are greatly affected by the caffeine [23-25].

According to some research reports, the caffeine consumption has great impact upon the depression. Low to moderate values of caffeine intake may decrease the depressive symptoms. Although high amounts caffeine intake can have negative effects. Several studies have reported that caffeine consumption is significantly associated with depressive symptoms and that it decreases the risk of depression [26]. Physical resistance performance is also made better by the moderate intakes of caffeine [27]. Increase in alertness and decrease in both the reduced sleepiness as well as fatigue are the common effects of moderate and low intakes of caffeine [28]. Insomnia is the main adverse effect of high caffeine intakes [29, 30].

The prevalence of caffeine dependence has been reported which indicate that the habitual caffeine users will show a rate of endorsement of clinically meaningful indicators of distress and functional impairment [31]. A condition for further study included is the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) which has been discussed in the diagnostic criteria for Caffeine Use Disorder [32]. The year wise work of different researchers upon the mental and cognitive effects of caffeine has been described in (Table 3).

Mental Properties/Year wise Work Dose Lara et al.,
2010
James et al, 2011 Ishak et al., 2012 Steven et al., 2013 Petar et al., 2014 Richard et al.,
2015
Cappelletti et al.,
2016
Temple et al., 2017 Callogen at al., 2018 Cornelis at al.,
2019
  Increased Alertness/Attention L D D D D D D D D D D
M D D D D D D D D D D
H D D D D D D D D D D
Cognitive Function L D D D D D D D D D D
M D D D D D D D D D D
H ND ND ND ND ND ND ND ND ND ND
Elevating Mood L ND ND ND ND ND ND ND ND ND ND
M D D D D D D D D D D
H D D D D D D D D D D
Cognitive Failure L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Depressive Symptoms L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D D D D D D D D D D
Psychiatric Disorders L ND ND ND ND ND ND ND ND ND ND
M D D D D D D D D D D
H D D D D D D D D D D
Psychotic/Mannic Disorders L ND ND ND ND ND ND ND ND ND ND
M ND ND ND D D D ND ND ND D
H ND ND ND ND D D D ND D ND
Obsessive Compulsive Disorders L ND ND ND ND ND ND ND ND ND ND
M D D D D D D ND ND ND ND
H D D ND D D D D D D D
Polymorphism of A2 Receptors L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND D D D D D ND D D D
Anxiety L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D D D D D D D D ND ND

Table 3. Mental Effects of Different Doses of Caffeine Intake

Low to moderate intakes of caffeine either in the form of a coffee or other caffeine sources is very beneficial in increasing the alertness and cognitive functions of body. It has been reported that the cognitive function in hemodialysis patients was improved by the coffee drinking which is the main source of caffeine intake. The higher mean scores on all tested cognitive domains were achieved by the regular coffee drinkers [33]. The beneficial impact on cognitive function in hemodialysis patients was noted by low to moderate caffeine intake due to selective enhancement of attention and vigilance on alertness and cognitive functions. Moderate amounts of caffeine intakes can impair the cognitive ability in regular caffeine users.

Patients with headache can be treated by the use of caffeinated headache medications, either alone or in combination with other treatments. The over-the-counter treatment of headache has demonstrated the role of caffeine in migraine and headache. Caffeine was found involved as the analgesic adjuvant in the acute treatment of primary headache. Efficacy of analgesics along with caffeine was found more effective rather than analgesics alone. But the nervousness (6.5%), nausea (4.3%), abdominal pain/ discomfort (4.1%), and dizziness (3.2%) were noted in patients taking heavy doses of caffeine based medications.

The mainly concentration, memory enhancement and physical performance are the main tasks of caffeine usage. The locomotors activity stimulation and anxiogenic-like effects of caffeine are mainly due to coffee and caffeine-containing products which may affect the central nervous system [34]. But more and more dependence upon caffeine has become significant leading towards individuals at risk for premature and unnatural death due to caffeine intoxication. Hence right caffeine doses are necessary for attaining its beneficial effects. Otherwise its lethal effects can destroy the mental health if taken in high dosage for longer time periods [35].

Coffee, tea, and chocolate are natural and main sources of caffeine and due to its common availability it has become the top most used psychoactive drug worldwide. Arousal, alertness, energy, and elevated mood are the main consequences of caffeine usage [33]. With the passage of time other caffeine sources has been introduced. Due to change in consumption patterns of the more traditional sources of caffeine there may be a need of increased scrutiny by health authorities and regulatory bodies about the overall consumption of caffeine [36,37].

But the rate of caffeine intake may vary accordingly as in pregnant and lactating women, children and adolescents, young adults, and people with underlying heart or other health conditions, such as mental illness [38]. An amount of caffeine may be potentially vulnerable to the negative effects; on the other hand the same dosage of caffeine may result in alertness, energy and cognitive function of a healthy adult.

Along with high caffeine dosage, the point of concern is also related to the body conditions of caffeine using persons. So the healthy adults can safely consume caffeine as compared to the vulnerable populations [39,40].

Due to its reported ergogenic properties like enhanced muscular force development and central nervous stimulation, the use of caffeine across sports and exercise is very common. All explore CAF expectancies, in conjunction with/without CAF pharmacology. Several studies have revealed the fact that the endurance capacity, weightlifting performance, simple reaction time and better memory were noted in persons by regular caffeine consumption [41]. But the fact remains in place that the caffeine consumption in regular users and nonregular users will imply different effects. Also the caffeine impact will vary person to person depending upon body capacity and body conditions.

Cardiovascular effects of caffeine

Caffeine affects the cardiovascular system, both in positive and negative ways depending upon the caffeine consumption. When taken in moderate amounts it can help with the proper blood flow, pressure and rate. No adverse effects can strike the cardiac system until the caffeine dose crosses the low to moderate intake values. Higher caffeine intakes can result in mild increase in blood pressure in hypertensive patients. So while taking caffeine you should be well familiar about your body capacity of caffeine consumption, only then you can fully enjoy caffeine benefits [42].

The relative risks of total cardiovascular disease (CVD), coronary heart disease (CHD) and acute myocardial infarction (AMI) has been reported by the excessive and generous intakes of caffeine on regular basis [43-45]. The effects on arrhythmia, heart failure, sudden cardiac arrest, stroke, blood pressure, hypertension by the regular and excessive users of caffeine beverages have evaluated the fact that excessive amounts of caffeine intakes will surely result in biomarkers of effect, including heart rate, cerebral blood flow, cardiac output, plasma homocysteine levels, serum cholesterol levels, electrocardiogram (EKG) parameters, heart rate variability, endothelial/platelet function and plasma/urine catecholamine levels [46].

While studying about cardiovascular effects of caffeine, it is still difficult to decide that what amounts of caffeine intakes can be counted as the excessive amounts. As the literature describes caffeine levels up to 600 mg/day in most cases may be mild, transient or reversible. A range of reversible and transient physiological effects are associated with the caffeine intake so these can result in the specific cardiovascular effects [47]. As data on taking caffeine above 600 mg/day is not up to the mark, so the identifiable daily greater uptakes of caffeine is so difficult. The decreased risks of total cardiovascular disease; arrhythmia; heart failure; blood pressure can be resulted from mild caffeine intakes.

The guidelines listed on caffeine consumption can never be strict to adhere as it is consumed both from natural and artificial sources (coffee and tea) as well. The proposed beneficial role in alertness, performance and energy expenditure along with its side effects has lead to the concerns regarding the safety of caffeine in the cardiovascular system. The question remains “Which dose is safe?, as the population. The population, type and dose of caffeine are the things that must be considered while taking the safe dose of caffeine that does not appear to adhere to the strict [48].

Potential concerns regarding, adverse cardiovascular sequel of a stimulant like caffeine are well observed. Reports on the excessive use of caffeinated beverages have revealed the conditions of hypertension, coronary artery disease, rhythmic disorders and heart failure in billions of patients worldwide. On the other hand, moderate amounts of caffeinated beverages may be proved beneficial for the coronary heart disease, heart failures and arrhythmia [49]. The year wise work of different researchers upon the cardiovascular effects of caffeine has been described in (Table 4).

Cardiovascular Properties/Year wise Work Dose Eumann et al.,
2010
Pelli et al, 2011 Sonsalla et al., 2012 Salvemini et al., 2013 Dinget al., 2014 Cappelletti et al.,
2015
Wilson et al.,
2016
Turnbull et al., 2017 Sharaet al., 2018 Zhouet al.,
2019
  Cardiovascular Disease(CVD) L ND ND ND ND ND ND ND ND ND ND
M ND ND D ND ND ND ND ND ND ND
H D D D D D D D D D D
Coronary Heart Disease (CHD) L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D D ND D D D D D D D
  Arrythmia L ND ND ND ND ND ND ND ND ND ND
M D D D D D D D D D D
H D ND D ND ND D ND D ND ND
Increased Heart Rate L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND D D D D ND D D D
High Blood Pressure L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D ND D D ND D D D D D
Heart Stroke L ND ND ND ND ND ND ND ND ND ND
M ND ND D ND ND D ND ND D ND
H D D D D D D D D D D
Endothelial/Platelets Disfunction L ND ND ND ND ND ND ND ND ND ND
M ND ND ND D D D ND ND ND D
H ND ND ND ND ND ND ND ND D ND
Sudden Cardiac Arrest L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Increased Cholesterol Levels L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND D D D ND D D ND
  Hypertension L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D ND ND D ND D ND D D D

Table 4. Cardiovascular Effects of Different Doses of Caffeine Intake.

Several research reports have revealed that positive effects of caffeine on the cardiovascular health are obtained. Many positive inotropic and chronotropic effects of caffeine on the cardiovascular effects of caffeine -like effects have been reported. The locomotor activity stimulation and anxiogenic effects of caffeine based products are due to their underlying motivations which result in concentration, memory enhancement and physical performance. The individuals' preexisting metabolism alterations or diseases along with caffeine’s interaction with other substances are the factors that may lead towards the lethal or toxic effects of caffeine, when caffeine intake is beyond the safe limits [50].

Generally speaking the coffee consumption has been reported as safe for human heart as evidenced by prospective cohorts, meta?analyses and clinical investigations. While talking aboiut the CVD risk factors, the chronic coffee intake consumption may result in little increase in blood pressure. As atherogenic lipid levels are raised due to the boiled coffee brewing so you should aware off the caffeine amounts and brewing methods of the coffee you are taking. Very little risk for atrial or ventricular arrhythmias due to coffee intakes has been reported in our society [51]. More critical research is required for the effects of newer caffeinated beverages with high caffeine and calories amounts per serving.

In most cases, only mild, transient, and reversible cardiovascular effects of caffeine without any long lasting adverse effects have been recorded for the caffeine consumption at levels up to 600 mg/day. As significant amounts of research reports on the effects of daily intakes greater than 600 mg are not available so the levels at which caffeine intake may cause harm to the cardiovascular system have not yet been established. But one thing is clear that no biomarkers of cardiac effect (heart failure; blood pressure, hypertension, CHD, CVD, arrhythmia) have been reported with moderate caffeine intakes even in regular coffee drinkers [52-55].

According to some research reports the cardiovascular activity in humans is highly affected when the widely used drug-caffeine is used without having any information about the caffeine amounts present in caffeinated and decaffeinated coffee. The mechanism of action of caffeine is related to increase in intracellular calcium concentration along with sensitization of dopamine receptors and the release of norepinephrine [56]. Very high doses of caffeine are involved with supraventricular and ventricular tachyarrhythmias, that may lead to the blockade of adenosine receptors. Although more research is required in order to fully understand the extended psychophysiological effects of caffeine as acute stimulant. Future progress in caffeine-related investigations involving research in psychophysiology and behavioral medicine will open more gateways to understand the upper intake levels of caffeine consumption. Until then the only way to avoid any bad cardiac events related with caffeine intakes is to be aware off the caffeine amounts of your caffeine based product intakes so that you may fix your caffeine to moderate level. Prohibition of caffeine intakes is not the very much good solution because it will snatch the joy of a friendly drink along with all its beneficiaries [57-60].

Sexual effects of caffeine

Caffeine has different effect upon male and female body. Greater positive subjective effects have been noted in case of male’s reproductive system as compared to that of female.

Caffeine would also have different effects on blood pressure of normal and hypertensive patients. The same amounts of caffeine may be adverse for a normal individual that may be suitable for lowering the blood pressure of a hypertensive male or female thus improving the phenomenon of reproduction as well [49].

Very little or no subjective responses to caffeine were involved with higher levels of estradiol. As the cardiac activity affected by caffeine was more prominent in females related to greater increase in diastolic blood pressure after caffeine intakes [61]. It was found interconnected with that of reproduction because the sexual life is highly dependent over the whole body conditions in spite of the reproductive organs only. The change in steroid hormone concentrations was also noted after caffeine intakes relevant with the gender differences. The estradiol level was found high with low blood pressure after caffeine consumption but in females it was totally opposite response with high blood pressure with high estradiol levels [62, 63].

Although no adverse effects of caffeine consumption has been reported for the modest level of caffeine consumption. Still caffeine consumption is considered as an unhealthy habit especially during pregnancy. As caffeine has an ability to accumulate in fetal tissues so consumption of caffeinated beverages during pregnancy may lead towards the fetal growth restriction, congenital malformations, stillbirth and long-term behavioral effects in offspring. The diverse pharmacological effects of caffeine may result in the fertility problems along with fetal growth and development [64].

It has been reported that the sperm concentration is highly affected by the long-term caffeine consumption although no effects on sperm motility, hepatic, cardiac, or renal functions has been reported yet. The cytoarchitecture of the testes and serum testosterone level of male offspring of Wistar rats has been reported after the maternal exposure to caffeine which would have adverse effects on the birth weight. According to some recent research, in some female hypertensive patients, the caffeinated beverages have been found to impose very positively related effects with sexual orgasm and sexual satisfaction (Gaskin et al). So the sexual activity in such patients would be improved by the long-term usage of caffeinated beverages in low to moderate amounts [65-69].

It has been reported that the greater risk of caffeine effects on the male and female reproductive systems would be possible in the individuals of subpopulations including unhealthy populations, individuals with preexisting conditions like co exposures and with a risk-taking behavior outcomes in comparison to that of healthy adults males and healthy pregnant women [70].

Caffeine intakes have been found very useful in cases of Erectile Dysfunction (ED). It was reported that a caffeine intakes of approximately 2-3 cups daily cups of coffee (170- 375 mg/day) may reduce the odds of prevalent ED. Even the overweight, obese and hypertensive men were observed with this reduction in ED after caffeine consumption. More factors involved in this phenomenon are remained to study yet [55].

According to some research reports there was found 42% less risk of ED in those men that were taking 1-2 cups of coffee on regular basis. A low risk of infertility was also reported in some hypertensive women having 1-2 cups of coffee regularly as it would sooth their muscles thus making the body more suitable for the ones that wish to conceive [71].

Higher caffeine intakes may negatively affect the male reproductive system because too much caffeine can damage the perm DNA. However low-caffeine intakes are involved in increasing fertility by improving the semen quality. So caffeine does not have a negative effect upon the male reproductive systems until it is taken in low to moderate amounts. In cases, where any crucial results related to reproduction are produced after caffeine consumption, there may be some involvement of the other factors like life style, weight and other physical activities [72].

Several studies have reported the positive effects of caffeine including a good effect on sex hormones including the reduction in clearance during the luteal phase. While regarding the caffeine effects on the male and female reproductive systems, no adverse effects would be resulted if moderate amounts of caffeine intakes. Even low to moderate caffeine intakes would help with the reproduction in both males and females by many means. In male and female atheletes, ergogenic effects from caffeine intakes were observed and caffeine was found to have the more positive effects on delayed-onset muscle soreness (DOMS) in case of male athletes [73].

On the other hand as caffeine is a psycho stimulant so during pregnancy and lactating period, it should be critically used within limits having full knowledge about the caffeine amounts present in the caffeinated products used by the women. Sometimes the person taking caffeine is not well aware of the caffeine amounts of the caffeinated beverages that he or she is taking so caffeine consumption may be out of the restricted amounts that may cause some issues especially during very sensitive time period (pregnancy, lactation) of women [73]. (Table 5) describes the year wise work about the caffeine effects on sexual health of both the males and females.

Sexual Properties/Year wise Work Dose Faraget al.,
2010
Brent et al, 2011 Hatch et al., 2012 Chenet al., 2013 Rudolph et al., 2014 Lopiz et al.,
2015
Doepkar et al.,
2016
Ricci et al., 2017 Callogen et al., 2018 Nisenblat et al.,
2019
  Male Fertility L D D D D D D D D D D
M D D D D D D D D D D
H D D D D D D D D D D
Low Sperm Quality L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Sperm Anuploidy L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND D ND D ND ND ND D ND
Low Sperm Motility L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Fecundability L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Low Serum Volumes L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H D D D D D D D D D D
Low Female Fertility L ND ND ND ND ND ND ND ND ND ND
M ND ND ND D D D ND ND ND D
H ND ND ND ND ND ND ND ND D ND
Genital Arousal Disorder L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND ND ND ND ND ND ND ND ND ND
Early Miscarriage L ND ND ND ND ND ND ND ND ND ND
M ND D D ND D D ND D D D
H D D D D D D D D D D
Ovulation Disorders L ND ND ND ND ND ND ND ND ND ND
M ND ND ND ND ND ND ND ND ND ND
H ND D ND ND ND D ND D ND ND

Table 5. Sexual Effects of Different Doses of Caffeine Intake.

Conclusion

In conclusion, the current study is about the caffeine consumption and its effects upon major human systems. Year wise work of different researchers about caffeine benefits have been discussed in order to get a current knowledge about the caffeine’s positive or negative effects over the body. As we are unaware of the caffeine amounts of the caffeinated products that we are taking so we don’t even have a idea about how much caffeine amounts we are using on daily basis. So in order to avoid any inconveniences created from the caffeine, we should be vigilant about the amounts of caffeine intakes.

As different bodies can have different capacities of the caffeine consumption so we should also know or estimate our body stamina of caffeine consumption. Even then we may be able to get caffeine benefits without completely prohibiting it due to its excepted side effects. As low to moderate amounts of caffeine consumption is usually tolerable so these amounts will benefit the whole human body but high amounts of caffeine may put on adverse effects on the body. So take caffeine only in low to moderate amounts and always try to avoid high caffeine intakes regularly.

References

  1. Addicott MA. Caffeine use disorder: A review of the evidence and future implications. Curr Addict Rep. 2014;1:186-92.
  2. Indexed at, Google Scholar, Cross Ref

  3. Agim ZS, Cannon JR. Dietary factors in the etiology of Parkinson’s disease. Biomed Res Int. 2015;2015.
  4. Indexed at, Google Scholar, Cross Ref

  5. Arnaud MJ. The pharmacology of caffeine. Prog Drug Res. 1987:273-313.
  6. Indexed at, Google Scholar, Cross Ref

  7. Azagba S, Langille D, Asbridge M. An emerging adolescent health risk: Caffeinated energy drink consumption patterns among high school students. Prev Med. 2014;62:54-9.
  8. Indexed at, Google Scholar, Cross Ref

  9. B Barnung R, H Nøst T, Ulven SM, Skeie G, S Olsen K. Coffee consumption and whole-blood gene expression in the Norwegian women and cancer post-genome cohort. Nutrients. 2018;10(8):1047.
  10. Indexed at, Google Scholar, Cross Ref

  11. Bonar EE, Green MR, Ashrafioun L. Characteristics of university students who mix alcohol and energy drinks. J Am Coll Health. 2017;65(4):288-93.
  12. Indexed at, Google Scholar, Cross Ref

  13. Browne ML, Hoyt AT, Feldkamp ML, Rasmussen SA, Marshall EG, Druschel CM, et al. Maternal caffeine intake and risk of selected birth defects in the National Birth Defects Prevention Study. Birth Defects Res. 2011;91(2):93-101.
  14. Indexed at, Google Scholar, Cross Ref

  15. Budney AJ, Brown PC, Griffiths RR, Hughes JR, Juliano LM. Caffeine withdrawal and dependence: a convenience survey among addiction professionals. J Caffeine Res. 2013;3(2):67-71.
  16. Indexed at, Google Scholar, Cross Ref

  17. O’Callaghan F, Muurlink O, Reid N. Effects of caffeine on sleep quality and daytime functioning. Risk Manag Healthc Policy. 2018:263-71.
  18. Indexed at, Google Scholar, Cross Ref

  19. Cappelletti S, Daria P, Sani G, Aromatario M. Caffeine: cognitive and physical performance enhancer or psychoactive drug?. Curr Neuropharmacol. 2015 ;13(1):71-88.  
  20. Indexed at, Google Scholar, Cross Ref

  21. Cappelletti S, Piacentino D, Fineschi V, Frati P, Cipolloni L, Aromatario M. Caffeine-related deaths: manner of deaths and categories at risk. Nutrients. 2018;10(5):611.
  22. Indexed at, Google Scholar, Cross Ref

  23. Ciruela F, Gómez-Soler M, Guidolin D, Borroto-Escuela DO, Agnati LF, Fuxe K, et al. Adenosine receptor containing oligomers: their role in the control of dopamine and glutamate neurotransmission in the brain. Biochimica et Biophysica Acta. 2011 May 1;1808(5):1245-55.
  24. Indexed at, Google Scholar, Cross Ref

  25. Chaudhary NS, Grandner MA, Jackson NJ, Chakravorty S. Caffeine consumption, insomnia, and sleep duration: Results from a nationally representative sample. Nutrition. 2016;32(11-12):1193-9.
  26. Indexed at, Google Scholar, Cross Ref

  27. Cornelis MC. The impact of caffeine and coffee on human health. Nutrients. 2019;11(2):416..
  28. Indexed at, Google Scholar, Cross Ref

  29. Cornelis MC. Toward systems epidemiology of coffee and health. Curr Opin Lipidol. 2015;26(1):20-9.
  30. Indexed at, Google Scholar, Cross Ref

  31. Cornelis MC, Munafo MR. Mendelian randomization studies of coffee and caffeine consumption. Nutrients. 2018;10(10):1343.
  32. Indexed at, Google Scholar, Cross Ref

  33. Doepker C, Franke K, Myers E, Goldberger JJ, Lieberman HR, O’Brien C, et al. 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. Nutrients. 2018;10(10):1536.
  34. Indexed at, Google Scholar, Cross Ref

  35. Doepker C, Lieberman HR, Smith AP, Peck JD, El-Sohemy A, Welsh BT. Caffeine: friend or foe?. Annu Rev Food Sci Technol. 2016;7:117-37.
  36. Indexed at, Google Scholar, Cross Ref

  37. Mesas AE, Leon-Muñoz LM, Rodriguez-Artalejo F, Lopez-Garcia E. The effect of coffee on blood pressure and cardiovascular disease in hypertensive individuals: a systematic review and meta-analysis. Am J Clin Nutr. 20111;94(4):1113-26.
  38. Indexed at, Google Scholar, Cross Ref

  39.  Evatt DP, Juliano LM, Griffiths RR. A brief manualized treatment for problematic caffeine use: A randomized control trial. J Consult Clin Psychol. 2016;84(2):113-21.
  40. Indexed at, Google Scholar, Cross Ref

  41. Farag NH, Whitsett TL, McKey BS, Wilson MF, Vincent AS, Everson-Rose SA, et al. Caffeine and blood pressure response: sex, age, and hormonal status. J Womens Health. 2010;19(6):1171-6..
  42. Indexed at, Google Scholar, Cross Ref

  43. Fulton JL, Dinas PC, Carrillo AE, Edsall JR, Ryan EJ, Ryan EJ. Impact of genetic variability on physiological responses to caffeine in humans: A systematic review. Nutrients. 2018;10(10):1373.
  44. Indexed at, Google Scholar, Cross Ref

  45. Gaskins AJ, Rich-Edwards JW, Williams PL, Toth TL, Missmer SA, Chavarro JE. Pre-pregnancy caffeine and caffeinated beverage intake and risk of spontaneous abortion. Eur J Nutr. 2018;57:107-17.  
  46. Indexed at, Google Scholar, Cross Ref

  47. Hahn KA, Wise LA, Rothman KJ, Mikkelsen EM, Brogly SB, Sørensen HT, et al. Caffeine and caffeinated beverage consumption and risk of spontaneous abortion. Hum Reprod. 2015;30(5):1246-55.
  48. Indexed at, Google Scholar, Cross Ref

  49. Haskell-Ramsay CF, Jackson PA, Forster JS, Dodd FL, Bowerbank SL, Kennedy DO. The acute effects of caffeinated black coffee on cognition and mood in healthy young and older adults. Nutrients. 2018;10(10):1386.
  50. Indexed at, Google Scholar, Cross Ref

  51. Hatch EE, Wise LA, Mikkelsen EM, Christensen T, Riis AH, Sørensen HT, et al. Caffeinated beverage and soda consumption and time to pregnancy. Epidemiol. 2012;23(3):393..  
  52. Indexed at, Google Scholar, Cross Ref

  53. Heinz AJ, de Wit H, Lilje TC, Kassel JD. The combined effects of alcohol, caffeine, and expectancies on subjective experience, impulsivity, and risk-taking. Exp Clin Psychopharmacol. 2013;21(3):222-34..
  54. Indexed at, Google Scholar, Cross Ref

  55. Hughes K, Quigg Z, Bellis MA, Calafat A, van Hasselt N, Kosir M, et al. Drunk and disorganised: relationships between bar characteristics and customer intoxication in European drinking environments. Int J Environ Res Public Health. 2012;9(11):4068-82.
  56. Indexed at, Google Scholar, Cross Ref

  57. Hoyt AT, Browne M, Richardson S, Romitti P, Druschel C, National Birth Defects Prevention Study. Maternal caffeine consumption and small for gestational age births: results from a population-based case–control study. Matern Child Health J Maternal. 2014;18:1540-51.
  58. Indexed at, Google Scholar, Cross Ref

  59. Kokaze A, Ishikawa M, Matsunaga N, Karita K, Yoshida M, Ochiai H, et al. Nadh dehydrogenase subunit-2 237 leu/met polymorphism influences the association of coffee consumption with serum chloride levels in male Japanese health checkup examinees: An exploratory cross-sectional analysis. Nutrients. 2018;10(10):1344.
  60. Indexed at, Google Scholar, Cross Ref

  61. Jones SC, Barrie L, Berry N. Why (not) alcohol energy drinks? A qualitative study with Australian university students. Drug Alcohol Rev. 2012;31(3):281-7.    
  62. Indexed at, Google Scholar, Cross Ref

  63. Kuang A, Erlund I, Herder C, Westerhuis JA, Tuomilehto J, Cornelis MC. Lipidomic response to coffee consumption. Nutrients. 2018;10(12):1851.
  64. Indexed at, Google Scholar, Cross Ref   

  65. Landais E, Moskal A, Mullee A, Nicolas G, Gunter MJ, Huybrechts I, et al. Coffee and tea consumption and the contribution of their added ingredients to total energy and nutrient intakes in 10 European countries: Benchmark data from the late 1990s. Nutrients. 2018;10(6):725.
  66. Indexed at, Google Scholar, Cross Ref

  67. Lee SY, Jung G, Jang MJ, Suh MW, Lee JH, Oh SH, et al. Association of coffee consumption with hearing and tinnitus based on a national population-based survey. Nutrients. 2018;10(10):1429.
  68. Indexed at, Google Scholar, Cross Ref

  69. Leviton A. Biases inherent in studies of coffee consumption in early pregnancy and the risks of subsequent events. Nutrients. 2018;10(9):1152.
  70. Indexed at, Google Scholar, Cross Ref

  71. Lopez DS, Wang R, Tsilidis KK, Zhu H, Daniel CR, Sinha A, et al. Role of caffeine intake on erectile dysfunction in US men: results from NHANES 2001-2004. PLoS One. 2015;10(4):e0123547.
  72. Indexed at, Google Scholar, Cross Ref

  73. Marczinski CA. Alcohol mixed with energy drinks: consumption patterns and motivations for use in US college students. Int J Environ Res Public Health. 2011;8(8):3232-45.
  74. Indexed at, Google Scholar, Cross Ref

  75. Marczinski CA, Fillmore MT, Bardgett ME, Howard MA. Effects of energy drinks mixed with alcohol on behavioral control: risks for college students consuming trendy cocktails. Alcohol Clin Exp Res. 2011;35(7):1282-92.
  76. Indexed at, Google Scholar, Cross Ref

  77. McLellan TM, Caldwell JA, Lieberman HR. A review of caffeine’s effects on cognitive, physical and occupational performance. Neurosci Biobehav Rev. 2016;71:294-312.
  78. Indexed at, Google Scholar, Cross Ref

  79. Miles?Chan JL, Charrière N, Grasser EK, Montani JP, Dulloo AG. The blood pressure?elevating effect of Red Bull energy drink is mimicked by caffeine but through different hemodynamic pathways. Physiol Rep. 2015;3(2):e12290.
  80. Indexed at, Google Scholar, Cross Ref

  81. Mulder EJ, Tegaldo L, Bruschettini P, Visser GH. Foetal response to maternal coffee intake: role of habitual versus non-habitual caffeine consumption. J Clin Psychopharmacol. 2010;24(11):1641-8.    
  82. Indexed at, Google Scholar, Cross Ref

  83. Navarro AM, Abasheva D, Martínez-González MÁ, Ruiz-Estigarribia L, Martín-Calvo N, Sánchez-Villegas A, et al. Coffee consumption and the risk of depression in a middle-aged cohort: the SUN project. Nutrients. 2018;10(9):1333.
  84. Indexed at, Google Scholar, Cross Ref

  85. Nawrot P, Jordan S, Eastwood J, Rotstein J, Hugenholtz A, Feeley M. Effects of caffeine on human health. Food Additives & Contaminants. 2003;20(1):1-30.
  86. Indexed at, Google Scholar, Cross Ref

  87. Nehlig A. Effects of coffee/caffeine on brain health and disease: What should I tell my patients?. Pract Neurol. 2016;16(2):89-95.
  88. Indexed at, Google Scholar, Cross Ref

  89. Oddy WH, O’sullivan TA. Energy drinks for children and adolescents. Bmj. 2009 Dec 15;339.
  90. Indexed at, Google Scholar, Cross Ref

  91. Ong AC, Myint PK, Potter JF. Pharmacological treatment of postprandial reductions in blood pressure: a systematic review. J Am Geriatr Soc. 2014;62(4):649-61.
  92. Indexed at, Google Scholar, Cross Ref

  93. Palagini L, Gemignani A, Banti S, Manconi M, Mauri M, Riemann D. Chronic sleep loss during pregnancy as a determinant of stress: impact on pregnancy outcome. Sleep Med. 2014;15(8):853-9.
  94. Indexed at, Google Scholar, Cross Ref

  95. Peacock A, Bruno R. Young adults who mix alcohol with energy drinks: typology of risk-taking behaviour. Addict Behav. 2015;45:252-8.
  96. Indexed at, Google Scholar, Cross Ref

  97. Peacock A, Bruno R, Martin FH, Carr A. The impact of alcohol and energy drink consumption on intoxication and risk?taking behavior . Alcohol Clin Exp Res. 2013;37(7):1234-42.
  98. Indexed at, Google Scholar, Cross Ref

  99. Pennay A, Lubman DI. Alcohol and energy drinks: a pilot study exploring patterns of consumption, social contexts, benefits and harms. BMC Res Notes. 2012;5(1):1-0.
  100. Indexed at, Google Scholar, Cross Ref

  101. Wilson PW, Bloom HL. Caffeine consumption and cardiovascular risks: Little cause for concern. J Am Heart Assoc. 2016;5(1):e003089.
  102. Indexed at, Google Scholar, Cross Ref

  103. Pilli R, Naidu MU, Pingali UR, Takallapally RK. Study of cardiovascular effects of caffeine in healthy human subjects, with special reference to pulse wave velocity using photoplethysmography. Int J Nut. Pharmacol Neurol Dis. 2012;2(3):243-50.
  104. Google Scholar

  105. Poole R, Kennedy OJ, Roderick P, Fallowfield JA, Hayes PC, Parkes J. Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes. BMJ. 2017;359.
  106. Indexed at, Google Scholar, Cross Ref

  107. Reyes CM, Cornelis MC. Caffeine in the diet: country-level consumption and guidelines. Nutrients. 2018;10(11):1772.
  108. Indexed at, Google Scholar, Cross Ref

  109. Ricci E, Noli S, Cipriani S, La Vecchia I, Chiaffarino F, Ferrari S, et al. Maternal and paternal caffeine intake and ART outcomes in couples referring to an Italian fertility clinic: a prospective cohort. Nutrients. 2018;10(8):1116.
  110. Indexed at, Google Scholar, Cross Ref

  111. Richards G, Smith A. Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children. J Clin Psychopharmacol. 2015;29(12):1236-47.
  112. Indexed at, Google Scholar, Cross Ref

  113. Shabir A, Hooton A, Tallis J, F Higgins M. The influence of caffeine expectancies on sport, exercise, and cognitive performance. Nutrients. 2018;10(10):1528.
  114. Indexed at, Google Scholar, Cross Ref

  115. Grant SS, Magruder KP, Friedman BH. Controlling for caffeine in cardiovascular research: a critical review. J Psychophysiol. 2018;133:193-201.
  116. Indexed at, Google Scholar, Cross Ref

  117. Salvemini D, Kim SF, Mollace V. Reciprocal regulation of the nitric oxide and cyclooxygenase pathway in pathophysiology: relevance and clinical implications. Am J Physiol Regul. 2013;304(7):R473-87.
  118. Indexed at, Google Scholar, Cross Ref

  119. Salas-Huetos A, Bulló M, Salas-Salvadó J. Dietary patterns, foods and nutrients in male fertility parameters and fecundability: a systematic review of observational studies. Hum Reprod Update. 2017;23(4):371-89.
  120. Indexed at, Google Scholar, Cross Ref

  121. Sonsalla PK, Wong LY, Harris SL, Richardson JR, Khobahy I, Li W, et al. Delayed caffeine treatment prevents nigral dopamine neuron loss in a progressive rat model of Parkinson's disease. Exp Neurol. 2012;234(2):482-7.
  122. Indexed at, Google Scholar, Cross Ref

  123. Temple JL, Bernard C, Lipshultz SE, Czachor JD, Westphal JA, Mestre MA. The safety of ingested caffeine: a comprehensive review. Front Psychiatry. 2017;8:80. 
  124. Indexed at, Google Scholar, Cross Ref

  125. Temple JL, Ziegler AM. Gender differences in subjective and physiological responses to caffeine and the role of steroid hormones. J Caffeine Res. 2011;1(1):41-8.
  126. Indexed at, Google Scholar, Cross Ref

  127. Thombs DL, O'Mara RJ, Tsukamoto M, Rossheim ME, Weiler RM, Merves ML, et al. Event-level analyses of energy drink consumption and alcohol intoxication in bar patrons. Addict Behav. 2010;35(4):325-30.
  128. Indexed at, Google Scholar, Cross Ref

  129. Turnbull D, Rodricks JV, Mariano GF, Chowdhury F. Caffeine and cardiovascular health. Regul Toxicol Pharmacol. 2017 Oct 1;89:165-85.
  130. Indexed at, Google Scholar, Cross Ref

  131. Ulbrich A, Hemberger SH, Loidl A, Dufek S, Pablik E, Fodor S, et al. Effects of alcohol mixed with energy drink and alcohol alone on subjective intoxication. Amino acids. 2013;45:1385-93.
  132. Indexed at, Google Scholar, Cross Ref

  133. Verster JC, Benjaminsen JM, Van Lanen JH, Van Stavel NM, Olivier B. Effects of mixing alcohol with energy drink on objective and subjective intoxication: results from a Dutch on-premise study. Psychopharmacol. 2015 Mar;232:835-42.
  134. Indexed at, Google Scholar, Cross Ref

  135. Vercambre MN, Berr C, Ritchie K, Kang JH. Caffeine and cognitive decline in elderly women at high vascular risk. J Alzheimer's Dis. 2013;35(2):413-21.
  136. Indexed at, Google Scholar, Cross Ref

  137. Volkow ND, Wang GJ, Logan J, Alexoff D, Fowler JS, Thanos PK, et al. Caffeine increases striatal dopamine D2/D3 receptor availability in the human brain. Transl Psychiatry. 2015;5(4):e549.
  138. Indexed at, Google Scholar, Cross Ref

  139. Wang L, Shen X, Wu Y, Zhang D. Coffee and caffeine consumption and depression: A meta-analysis of observational studies. Aust N Z J Psychiatry. 2016;50(3):228-42.
  140. Indexed at, Google Scholar, Cross Ref

  141. Wikoff D, Welsh BT, Henderson R, Brorby GP, Britt J, Myers E, et al. Systematic review of the potential adverse effects of caffeine consumption in healthy adults, pregnant women, adolescents, and children. Food Chem Toxicol. 2017;109:585-648.
  142. Indexed at, Google Scholar, Cross Ref

  143. Yaya I, Marcellin F, Costa M, Morlat P, Protopopescu C, Pialoux G, et al. Impact of alcohol and coffee intake on the risk of advanced liver fibrosis: a longitudinal analysis in HIV-HCV coinfected patients (ANRS CO-13 HEPAVIH cohort). Nutrients. 2018;10(6):705.
  144. Indexed at, Google Scholar, Cross Ref

  145. Zhou A, Hyppönen E. Long-term coffee consumption, caffeine metabolism genetics, and risk of cardiovascular disease: a prospective analysis of up to 347,077 individuals and 8368 cases. Am J Clin Nutr. 2019;109(3):509-16.
  146. Indexed at, Google Scholar, Cross Ref

Get the App