Is Your Caffeine Addiction a Preventative Health Care Measure

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1 Is Your Caffeine Addiction a Preventative Health Care Measure Drink Your Coffee and Enjoy it Too by Alison Chen, ND info@dralisonchen.com DrAlisonChen.com Introduction Who s addicted to caffeine? Not me! you say in an offended tone. In the United States, 73% of children and 87% of adults are regularly using caffeine. [1] Over the years, caffeine has been abused and modified with sugars, food colouring, and unpronounceable additives. Coffee is the most commonly ingested form of caffeine, but there is a whole line of beverages and products that range from being psychologically damaging to being overwhelmed with health benefits. Not all caffeine is bad for you. In fact, caffeine in itself is not bad. It s the frequency, amounts, and dependencies people have to it that are most concerning. Most people need their coffee to get them functioning enough to start or continue their day. It takes a toll on your adrenal glands for someone who has already pushed their stress to the max. I Explain Caffeine Abuse to My Patients With this Analogue: Imagine you have a pair of soaked sponges. They are so full that the minute you pick them up, they spill over with excess water. These are your healthy adrenal glands that are spilling over with adrenaline, epinephrin, cortisol, and other energy-producing and stress-regulating hormones. With each task you take on in life, you start to squeeze the sponges, little by little: College parties Buying a car Cramming for exams Moving in with your boyfriend Finding work in a big city Planning your wedding

2 Planning your honeymoon Paying off your debt Having your first child Getting promoted Moving etc. If you don t take the time to recharge your batteries or in this case refill your sponges they will slowly start to dry out. When your daily tasks start to become major stressors and you fall into a reactive mindset, caffeine can save the day. Caffeine does a fantastic job at squeezing your sponges (stimulating your adrenals) to release more water (energy-producing and stress-regulating hormones). Unfortunately, when you re in survival mode, you are often not taking the time to properly rest and nourish your adrenals. So, your sponges start to dry up even more. You require more cups of coffee to wring out the last few drops of adrenaline and cortisol until you eventually reach adrenal fatigue. Your body is no longer able to function properly and you can physically collapse. This is often seen after someone finishes a big project, goes out to celebrate, and then immediately gets sick. Of course, the mechanisms of action for caffeine are much more complex than that. Like many addictions, when caffeine is abused, it can do us great harm. However, its properties are beneficial, and can be healthful when used appropriately and with the proper adrenal support. Caffeine Is the World s Most Popular Drug Caffeine is a methylxanthine compound that mainly causes neurohormonal stimulation and activation of the sympathetic nervous system. [2] This results in an increase in blood catecholamines and cortisol that allows the body to adapt to stressors. [3][4] In the heart, caffeine acts as an adenosine receptor antagonist, which begins reactions that mimic the effects of epinephrine. [2] The secretion of epinephrine (and norepinephrine) increases the force and rate of heart contraction, thereby raising blood pressure and heart rate. [3] Caffeine Addiction: Is it a Preventative Health-Care Measure? Caffeine has been used by many to enhance mood and energy, to improve athletic performance, or as a medicine (e.g. headache relief, diuretic, antioxidant), but most commonly, to counteract the effects of insufficient sleep. [1] However, like any effective drug, there are potential negative side effects. Let s have a look at the actions of caffeine:

3 Stimulant Cognitive and Mental Support Studies of caffeine on cognitive and mental acuity show conflicting data. There are many studies finding acute caffeine use consistently improves psychomotor speed and vigilance as well as simple and choice reaction times, increases alertness, improves short-term recall, and lowers perceived fatigue. [1] However, these studies measure cognitive abilities pre- and postdose, which may show an exaggerated effect if the participant is experiencing a period of caffeine deprivation prior to receiving a single bolas dose. [1] Some studies use nonhabituated caffeine users to remedy this study flaw and still experience similar positive performance enhancing effects from caffeine. [1] Other studies found no significant impact on reaction time, vigilance, or decisionmaking, and found that caffeine may in fact cause long-term negative impact in motor skills, memory, and learning with frequent use. [1] Overall, caffeine use as a cognitive stimulant may be beneficial if not abused or as a replacement for insufficient sleep. Mood Stimulant Caffeine at a dose of 300 mg has been shown to increase anxiety and tension, especially when paired with stressful tasks. [4] Patients with panic disorders have an increased sensitivity to low doses of caffeine, showing signs of anxiety, nervousness, fear, and tremors. [4] Hallucinatory experiences are reported with > 300 mg of caffeine (~ 7 cups of coffee) per day, which may be due to the physiological effects of cortisol release during stressful periods. [4] Cardiovascular Disease Caffeine increases acute risk for atrial fibrillation (irregular heart contraction) and myocardial infarction (heart attacks) in those with existing heart conditions. These cases are especially seen at high caffeine doses and in combination with other stimulants, as seen with some energy drinks. [2]

4 Tachycardia (fast heart rate) and arrhythmia (irregular heart rate) symptoms typically arise with > 200 mg of caffeine ingestion and have been shown to adversely affect arterial stiffness. [4] Although studies of chronic caffeine use have reported no overall increase in atrial fibrillation (AF) risk, acute caffeine consumption increases blood renin, epinephrine and norepinephrine levels, blood pressure, heart rate, and ECG markers for AF. [2] However, coffee and tea also contain important antioxidant sources that can decrease inflammation and heart tissue dysfunction, and can be protective against AF. [2] Exercise and Fat-Loss Support Caffeine supplementation can aid in improving exercise performance by increasing muscle endurance as well as glycogen resynthesis (form of energy), and help facilitate fat loss. [5] The adrenal hormones released with caffeine consumption allow free fatty acids to be used by the muscle during exercise and spare glycogen use, which improves physical performance. [3] Exercise in itself is an antidiabetic medicine. It increases exercise-induced insulinsensitivity responses. Despite pure caffeine supplementation enhancing exercise performance, it may reduce the exercise-induced blood-glucose regulation. [5] Special Report: Green Coffee Bean Green coffee bean and caffeine have come and gone as the latest weight-loss fad. Do they really work? Let s look at the research: [5] Green coffee bean by weight is composed of 50% chlorogenic acid and 3% caffeine. Chlorogenic acid has been reported to increase blood-glucose disposal during oral glucose tolerance testing (OGTT) in animals and humans. One study showed no effect on glucose and insulin concentrations when green coffee bean was consumed postexercise. However, other studies using higher doses of chlorogenic acid (450 mg) given to exercisers minutes prior to activities showed a significant decrease in blood-glucose levels due to the delayed peak effect of chlorogenic acid. Another small study used chlorogenic acid enriched instant coffee with overweight and obese participants for 12 weeks and found a significant effect on the absorption and utilization of glucose from their diet. When compared to the control group who only drank instant coffee, the chlorogenic acid enriched group lost an average of 5.4 kg compared to 1.7 kg in the control group. [6]

5 Sleep Most people abuse caffeine for its stimulating effect in the early mornings to counter lack of sleep. Others use it midday to defeat food comas, boredom, or exhaustion. However, when stimulants are taken too late in the day, especially two hours or less before bed, sleep quantity and quality are severely affected. Even a study with a group of female athletes who took caffeine 45 minutes prior to intense exercise for 90 minutes in the evening experienced sleep latency and impaired sleep quality. [7] Antioxidant Cancer Protection Many studies have found supporting evidence that tea is a powerful anticancer agent, but what about isolated caffeine? Clinical findings demonstrate various anticancer properties of caffeine and caffeic acid against breast cancer (estrogen- and nonestrogen-dominant) that may sensitize tumour cells to tamoxifen treatment and reduce breast-cancer growth. [8] Reduced Risk of Parkinson s Disease High black-tea and coffee intake was significantly associated with lowered risk of Parkinson s disease. [9] However, in women using hormone therapy, high intake was correlated to an increased Parkinson s disease risk and mortality. [9] There are conflicting results with this study, which requires more research to be conducted. Diuretic Kidney Function Acute caffeine ingestion can increase urine volume and kidney function. This prompts concerns for fluid balance, especially during exercise and sporting events. [10] However, with adequate hydration before exercise, these concerns are unwarranted. [10] Although there is an increase in urine and calcium excretion, caffeine-containing beverages have actually been shown to lower the risk of kidney stones. [11] People with chronic renal conditions should carefully monitor their caffeine consumption to avoid excessive burden on their kidneys. Other Mechanisms Reduced Iron Absorption Excess caffeine has been shown to decrease absorption of nonheme iron (nonmeat

6 sources), and therefore, caution should be taken in people with iron-deficient anemia, especially vegan and vegetarians. [12] However, caffeine seems to affect iron status only in those with current risk of anemia. [12] Pregnancy, Children And Caffeine Prenatal coffee ingestion was negatively associated with Behavior Rating Scale of the infant. [13] Caution should be taken by men who heavily consume energy beverages and food supplements, to avoid the potentially deleterious effect of caffeine on sperm quality. [14] Moderate consumption of caffeine appears to be safe to male reproductive health. [14] Research suggests an association between coffee and tea consumption in children younger than two years old with type 1 diabetes and a three-fold risk of severe kindergarten obesity. [15] Children and adolescent caffeine use increases risk of depression; sleep difficulties; being overweight; and substance use; and has concerning physiological, behavioral, and psychological effects. [15] Who s the Caffeine King? The amount of caffeine in your food and beverages depends on the quality, process, and source. The Caffeine Database is a good reference checker to ensure you re staying below Health Canada s daily caffeine limit of 400 mg/d. The most common forms of caffeine are coffee, tea, soda, energy drinks, sweet foods, and medication. Coffee Coffee is the world s favourite beverage, with an estimated 1.5 billion cups drunk per day. [6] Studies show an increased risk in cardiovascular heart disease (CVD) with

7 Caffeine Content in Coffee Type of coffee Size Caffeine Brewed 8 oz. (237 ml) mg Brewed, decaffeinated 8 oz. (237 ml) 2 12 mg Brewed, single-serve varieties 8 oz. (237 ml) mg Brewed, single-serve varieties, decaffeinated 8 oz. (237 ml) 2 4 mg Espresso, restaurant-style 1 oz. (30 ml) mg Espresso, restaurant-style, decaffeinated 1 oz. (30 ml) 0 15 mg Instant 8 oz. (237 ml) mg Instant, decaffeinated 8 oz. (237 ml) 2 12 mg Specialty drink (latte or mocha) 8 oz. (237 ml) mg Adapted from Journal of Food Science, 2010; Pediatrics, 2011; USDA National Nutrient Database for Standard Reference, Release 26; Journal of Analytical Toxicology, 2006; Starbucks, 2014; Food and Chemical Toxicology, 2014; Keurig, more than six cups of coffee per day in former or current smokers. [4] In patients with confirmed CVD, heavy coffee consumption (> 10 cups/ day) was associated with a significant risk of sudden cardiac arrest. [4] On the other hand, there appears to be no association between moderate coffee intake and cardiovascular events, even in patients with a history of myocardial infarction. [4] Note: Unfiltered coffee is a significant source of cafestol and kahweol compounds that raise cholesterol and can be detrimental to your health. The table above shows stats on the amounts of caffeine in coffee. Even the same amount of drip coffee (16 oz.) from different beans, brews, and stores contain a surprising range of caffeine content. Caffeinated Tea Tea is the second most-consumed beverage worldwide. [16] Caffeinated tea is produced from the leaves, buds, or delicate stems of plants, most commonly Camellia genus. It contains several chemical compounds, such as polyphenols (mainly catechins), caffeine (2 4%), theophylline, and l theanine. Polyphenols are responsible for tea s significant antioxidant and anticarcinogenic properties. [16] Drinking at least four cups of tea per day (irrespective of the type) may reduce the risk of type 2 diabetes by 20%. [12]

8 The three main types of teas vary based on flavour, colour, and composition: Black Tea: Full fermentation of the plant Oolong Tea: Semifermentation Green Tea: No fermentation One teaspoon of dried leaves in eight ounces of boiling water makes one cup of tea, and contains 14 to 65 mg of caffeine. [12] Caffeine content increases with the length of steeping and younger tea leaves. [12] Consuming eight cups of caffeinated tea or less per day minimizes any risk of excess caffeine intake. [12] Drinking at least three cups of black tea reduces the risk of cardiovascular disease, [12] and has a strong protective effect against Parkinson s disease. [9] Green tea has antioxidant properties six times stronger than black tea. [16] Regular consumption of green tea is a strong preventative factor for bladder, lung, stomach, prostate, and colon cancer. [16] In addition to its strong antioxidant effects, green tea also has many other health benefits: Anti-inflammatory Antimicrobial Antidiabetic Improves cholesterol levels Decreases risk of heart disease Reduces neurodegenerative disease risk Increases alertness and focus Caffeine Content in Tea Calms digestive system Protects cartilage Supports kidney function Type of tea Size Caffeine Brewed tea Black tea 8 oz. (237 ml) mg Black tea, decaffeinated 8 oz. (237 ml) 0 12 mg Green tea 8 oz. (237 ml) mg Iced tea Instant, prepared with water 8 oz. (237 ml) mg Ready-to-drink, bottled 8 oz. (237 ml) 5 40 mg Adapted from Journal of Food Science, 2010; Pediatrics, 2011; Journal of Analytical Toxicology, 2008; USDA National Nutrient Database for Standard Reference, Release 26; Journal of Analytical Toxicology, 2006; Starbucks, 2014; Food and Chemical Toxicology, 2014.

9 Special Report: Yerba Mate Yerba mate is a popular drink in South America. It is a crop tree native to the subtropical rainforest of Argentina, Brazil, and Paraguay. The dried leaves and aerial parts of the Ilex paraguariensis plant contain the caffeine (1.5 mg/g), chlorogenic acid (2.1 mg/g), phenols, and saponin compounds that are used as everyday substitutions for coffee. [17] Yerba mate has significant antioxidant properties and has been used for weight loss in obese patients. Soda Caffeinated soda products not only cause excessive stimulation and irregular blood glucose regulation in children and adults, but also increase the risk of obesity, diabetes, cardiometabolic diseases, and osteoporosis. [18] Soda pop (in general) is harmful, especially to children, because of its acidic nature that can decrease the amount of calcium absorption into healthy bone formation and growth. [18] It also increases the risk of calcium-based kidney stones [19] and dental cavities. [20] The worst soda offenders for high levels of caffeine are mentioned in the accompanying table, right. Caffeine Content in Sodas Type of soft dink Size Caffeine A&W Root Beer 12 oz. (355 ml) 0 mg Barq s Root Beer 12 oz. (355 ml) mg Coca-Cola 12 oz. (355 ml) mg Diet Coke 12 oz. (355 ml) mg Diet Pepsi 12 oz. (355 ml) mg Dr Pepper (regular or diet) 12 oz. (355 ml) mg Mountain Dew (regular or diet) 12 oz. (355 ml) mg Mug Root Beer (regular or diet) 12 oz. (355 ml) 0 mg 7UP 12 oz. (355 ml) 0 mg Pepsi 12 oz. (355 ml) mg Sierra Mist (regular or diet) 12 oz. (355 ml) 0 mg Sprite (regular or diet) 12 oz. (355 ml) 0 mg Adapted from Journal of Food Science, 2010; Pediatrics, 2011; USDA National Nutrient Database for Standard Reference, Release 26; Journal of Food Science, 2007; Journal of Analytical Toxicology, 2006; Pepsico, 2014; Coca-Cola, 2014; Dr Pepper, 2014; A&W Root Beer; 7UP. Energy Drinks and Shots Especially among adolescents and young adults, energy drink consumption represents a global public health problem. [4] Energy drinks are a relatively new phenomenon. In the United States, nearly 200 new brands of energy drinks were launched between 2006 and 2007, and in 2004, 1.5 billion cans of Red Bull were sold. [4] In 2011, the FDA reported energy drinks sold $6.38

10 billion of products and accounted for over 20,000 emergency room visits. Meanwhile, caffeine-based energy-shot products accounted for $1.3 billion in sales in [21] A Korean sales analysis on the market showed that energy drinks are sought mostly by young people and athletes those in their teens and 20s accounted for 23% and 41% of the consumers, respectively. [3] Energy drinks and shots such as Monster, Red Bull, Hot Six, 5 Hour Energy, and Full Throttle contain stimulants and other substances, including high doses of caffeine along with taurine, ginseng, guarana, theophylline, sugars, vitamins, amino acids, and herbs. [2] Although manufacturers of energy drinks claim that these beverages are beneficial in that they can boost energy as well as physical performance and improve cognitive performance, there is insufficient scientific evidence to support these claims. [4] The US Food and Drug Administration does not adequately regulate the marketing of energy drinks in the United States. The caffeine content in these energy drinks ranges from 50 mg to 500 mg. [4] Energy drinks and shots were primarily designed for athletes to increase physical performance. It s reported that 74% of elite-level athletes ingest caffeinated products (with carbohydrates and protein sources) prior to competition to gain numerous benefits such as improved endurance performance, strength performance, reaction time, and fat oxidation, as well as for a reduction in subjective perceived exertion. [21] However, several studies have found that there is no significant improvement in physical or mental performance when comparing caffeine to energy drinks with taurine or niacin. [22] Therefore, the benefits of energy drinks such as Red Bull are most likely due to the effects of caffeine, with the other ingredients not likely to offer additional benefit. [23] Another reason to avoid energy drinks and shots is the acute negative effects that have been reported of triggering cardiac arrhythmias and increasing blood pressure and heart rate, leading to atrial Caffeine Content in Energy Drinks Type of energy dink Size Caffeine Amp (regular or sugar-free) 8 oz. (237 ml) mg 5 Hour Energy shot 2 oz. (60 ml) mg Full Throttle (regular or sugar-free) 8 oz. (237 ml) mg Red Bull (regular or sugar-free) 8.4 oz. (248 ml) mg Rockstar (regular or sugar-free) 8 oz. (237 ml) mg Adapted from Journal of Food Science, 2010; American Academy of Pediatrics, 2011; USDA National Nutrient Database for Standard Reference, Release 26; Consumer Reports, 2014; Mayo Clinic Proceedings, 2010; 5 Hour Energy, 2014; Pepsico, 2014; Full Throttle; Red Bull.

11 fibrillation. [2] Other studies have suggested energy drinks can precipitate first-onset seizures, contribute to strokes, and cause renal impairment from the diuretic effects. [4] Further long-term studies are required on the negative effects of energy drinks. Sweets Chocolate, stimulating herbs, and certain nutraceuticals have become a common form of sweet caffeinated snacks. The dosages of caffeine are often much lower than the previous beverages we ve discussed, with dark chocolate (> 70% cacao) having many antioxidant and cardiovascular health benefits. Medication Certain medications contain caffeine to act as headache relief (e.g. Excedrin) and for restoring mental alertness (e.g. NoDoz). These medications can be avoided by careful management of caffeine withdrawal (see below) and adequate sleep. Isolated caffeine supplementation may be helpful in doses < 400 mg/d for improving exercise performance, but is best taken with carbohydrates Caffeine Content in Sweets Type of sweet Size Caffeine Chocolate chips, semisweet 1 cup (168 g) 104 mg Dark chocolate coated coffee beans 28 pieces 336 mg Energy mints 2 mints mg Adapted from Pediatrics, 2011; USDA National Nutrient Database for Standard Reference, Release 26; Food and Drug Administration, 2014; Vroom Foods, Inc., Caffeine Content in Medications Type of medication Size Caffeine Excedrin Extra Strength 1 tablet 65 mg NoDoz Max Strength 1 tablet 200 mg Adapted from Pediatrics, 2011; USDA National Nutrient Database for Standard Reference, Release 26; Food and Drug Administration, 2014; NoDoz, 2014; Excedrin, and protein. [21] Improved physical performance have been found in athletes taking between mg/kg body weight of caffeine prior to exercise. [3] The Key Take-Home Message The daily limit of caffeine intake is 400 mg. Beverages with > 0.15 mg/ml of caffeine are highly caffeinated drinks and should be avoided by those sensitive to caffeine, such as children and pregnant women. [3] Health Canada recommends the daily caffeine intake for children should be < 2.5 mg/kg of body weight. [15]

12 Pregnant women should limit coffee consumption to < 3 cups/d (< 300 mg caffeine) in order to avoid the risk of spontaneous abortion or impaired fetal growth. [6] People with iron deficiency should limit their caffeine intake. [12] Drinking moderate amounts (3 4 cups/d) of filtered coffee and caffeinated teas can be full of health benefits. [4][12] Avoid caffeine products before bed. Avoid high doses of caffeine if you have a history of heart complications, high blood pressure, tachycardia, anxiety, panic attacks, seizures, severe kidney disease, or history of tobacco use. Don t drink energy drinks; they aren t any more beneficial than caffeine and have potential negative side effects. [21][23] Carefully monitor your health if you do frequently consume energy drinks or high doses of caffeine. Keep hydrated with pure water while consuming caffeine. Caffeine can improve neuromuscular function when taken prior to exercise, with a potential to reduce blood glucose and fat loss. But more importantly, exercise to lose fat! Top 10 Caffeine Withdrawal Symptoms 1. Headache A caffeine headache usually starts behind the eyes and then moves up the front of the head. 2. Sleepiness This just isn t your normal tiredness, this is sitting up straight but still can t keep your eyes open tiredness. 3. Irritability Everyone and everything gets on your last nerve. It s best just to lock yourself in your room during this stage. 4. Lethargy Forget about productivity at this stage because you ll be unmotivated to do anything from the feeling of the lack of energy. 5. Constipation Caffeine stimulates the bowel, so without its daily dose the colon gets a little cranky too. 6. Depression Caffeine withdrawal can take away all hope for living. Temporary blues are one thing, but if you already struggle with depression this could be a big issue. 7. Muscle Pain, Stiffness, Cramping If you normally have some caffeine prior to exercise then during caffeine withdrawal you could feel as though your muscles have weights strapped to them. 8. Lack of Concentration Forget school, studying, brain surgery, or jet engine repair during this stage of withdrawal. 9. Flu-like symptoms Stuffy nose, blocked sinuses, and sinus pressure have all been reported by people withdrawing from caffeine. 10. Insomnia Some people actually can t sleep when going through caffeine withdrawal. Caffeine intake > 3 mg/kg of body weight resulted in side effects such as stomach pain, anxiety, hypersensitiveness, and faster heartbeats. [3] Large doses > 10 g have been fatal and result in rare cases of rhabdomyolysis and acute renal failure. [24]

13 How to Avoid Caffeine Withdrawal If you ve ever decided to give up your energy drink addiction or start to reduce your daily intake of coffee, you might have noticed a few key caffeine withdrawal symptoms, such as those enunciated in the table, right. Here are important tips to remember while weaning off of your caffeine addiction: Replace your current caffeine intake with teas (black, green, yerba), coffee, or supplements to start. This will keep your caffeine levels more regulated and avoid a drastic crash. Slowly reduce consumption of products with high caffeine content. Don t go from 10 RockStars a day to a cup of green tea in a week! Support your adrenals prior to and during stressful events with adaptogenic herbs such as Ashwaghanda, Rhodiola, Astragalus, and Eleutherococcus. Protect your heart and mind with a healthy, well-balanced meal full of colourful vegetables, lean protein, and healthy fats (e.g. fish, coconut, olive oil, nuts, and seeds). Start a sleep routine by doing healthy sleep hygiene practices before you go to bed, going to sleep at consistent time, and getting 7 9 hours per night. Drink more water to stay hydrated and focused. Exercise and keep your body releasing feel-good hormones and sweating with daily activities. Maintain a healthy state of mind with regular practices, such as meditation, deep breathing, and gratitude journaling. References 1. Harvanko, A.M., et al. The effect of self-regulated caffeine use on cognition in young adults. Human Psychopharmacology. Vol. 30, No. 2 (2015): Turagam, M.K., et al. Commonly consumed beverages in daily life: Do they cause atrial fibrillation? Clinical Cardiology. Vol. 38, No. 5 (2015): An, S.M., J.S. Park, and S.H. Kim. Effect of energy drink dose on exercise capacity, heart rate recovery and heart rate variability after highintensity exercise. Journal of Exercise Nutrition & Biochemistry. Vol. 18, No. 1 (2014): Ibrahim, N.K. and R. Iftikhar. Energy drinks: Getting wings but at what health cost? Pakistan Journal of Medical Sciences. Vol. 30, No. 6 (2014): Beam, J.R., et al. Effect of post-exercise caffeine and green coffee bean extract consumption on blood glucose and insulin concentrations. Nutrition. Vol. 31, No. 2 (2015): Thom, E. The effect of chlorogenic acid enriched coffee on glucose absorption in healthy volunteers and its effect on body mass when used long-term in overweight and obese people. The Journal of International Medical Research. Vol. 35, No. 6 (2007): Ali, A., et al. The effect of caffeine ingestion during evening exercise on subsequent sleep quality in females. International Journal of Sports Medicine. Vol. 36, No. 6 (2015): Rosendahl, A.H., et al. Caffeine and caffeic acid inhibit growth and modify estrogen receptor and insulin-like growth factor I receptor (IGF-IR) levels in human breast cancer. Clinical Cancer Research. Vol. 21, No. 8 (2015): Agim, Z.S., and J.R. Cannon. Dietary factors in the etiology of Parkinson s disease. BioMed Research International. Vol (2015): Zhang, Y., et al. Caffeine and diuresis during rest and exercise: A meta-analysis. Journal of Science and Medicine in Sport. Vol. 18, No. 5 (2015): Ferraro, P.M., et al. Caffeine intake and the risk of kidney stones. The American Journal of Clinical Nutrition. Vol. 100, No. 6 (2014):

14 12. Wierzejska, R. Tea and health A review of the current state of knowledge. Przegla d Epidemiologiczny.Vol. 68, No. 3 (2014): , Engle, P.L., et al. Effects of discontinuing coffee intake on iron deficient Guatemalan toddlers cognitive development and sleep. Early Human Development. Vol. 53, No. 3 (1999): Dias, T.R., et al. Dose-dependent effects of caffeine in human Sertoli cells metabolism and oxidative profile: Relevance for male fertility. Toxicology. Vol. 328 (2015): Burnham, L., et al. Breastfeeding and coffee consumption in children younger than 2 years in Boston, Massachusetts, USA. Journal of Human Lactation. Vol. 31, No. 2 (2015): Conde, V.R., et al. Tea (Camellia sinensis (L.)): A putative anticancer agent in bladder carcinoma? Anti-Cancer Agents in Medicinal Chemistry. Vol. 15, No. 1 (2015): Bojić, M., et al. Determination of flavonoids, phenolic acids, and xanthines in mate tea (Ilex paraguariensis St. Hil.). Journal of Analytical Methods in Chemistry. Vol (2013): Mahmood, M., et al. Health effects of soda drinking in adolescent girls in the United Arab Emirates. Journal of Critical Care. Vol. 23, No. 3 (2008): Passman, C.M., et al. Effect of soda consumption on urinary stone risk parameters. Journal of Endourology. Vol. 23, No. 3 (2009): Kaplowitz, G.J. An update on the dangers of soda pop. Dental Assistant. Vol. 80, No. 4 (2011): 14 16, 18 20, passim; quiz Seifert, J.G., and D.A. Connor. The influence of commercial energy shots on response time and power output in recreational cyclists. Journal of the International Society of Sports Nutrition. Vol. 11, No. 1 (2014): Kammerer, M., et al. Effects of energy drink major bioactive compounds on the performance of young adults in fitness and cognitive tests: A randomized controlled trial. Journal of the International Society of Sports Nutrition. Vol. 11, No. 1 (2014): Quinlivan, A., et al. The effects of Red Bull energy drink compared with caffeine on cycling time trial performance. International Journal of Sports Physiology and Performance. Vol. 10, No. 7 (2015): Campana, C., P.L. Griffin, and E.L. Simon. Caffeine overdose resulting in severe rhabdomyolysis and acute renal failure. The American Journal of Emergency Medicine. Vol. 32, No. 1 (2014): 111.e3 4.