See ((Coffee))1,3,7-trimethylxanthine, a natural purine alkaloid.
An adenosine receptor antagonist, that accounts for its stimulant action.
There is a higher genetic predisposition to higher caffeine levels that is linked to reduce body fat and type 2 diabetes risk.
It spreads throughout the body and crosses the blood-brain barrier.
A stimulant that can influence neuronal control pathways in the central and peripheral nervous systems.
A bio-active ingredient found in commonly consumed beverages such as coffee, tea, and sodas.
Short-term physiological effects of caffeine include increased blood pressure and sympathetic nerve outflow.
In excessive doses it can be harmful.
Caffeine can also be synthesized pharmacologically and added to foods or non-alcoholic or energy drinks or commercial preparations to reduce fatigue and increase psychic reactivity.
The main sources of caffeine consumption include coffee, tea, and soft drinks.
Some studies show that caffeine intake is linked to weight loss and reduced body mass index (BMI) and fat mass.
Caffeine intake may thus lower the risk of conditions linked to overweight or obesity, such as type 2 diabetes or cardiovascular disease.
Caffeine intake can contribute to pain relief when added to analgesic agents.
Habitual consumption of caffeine may inhibit physiological short-term effects.
Caffeine is known to shortly increase blood pressure, whereas long term consumption could decrease blood pressure.
Consumption of caffeine increases parasympathetic activity in habitual caffeine consumers.
Capable of increasing work capacity while individuals perform strenuous tasks, likely due to caffeine’s ability to increase sympathetic nerve outflow.
Has tendency to inhibit parasympathetic activity in non-habitual consumers.
The parasympathetic activity increases in the supine position.
Caffeine may influence autonomic activity differently for individuals who are more active or elderly.
Probably most frequently consumed drug in the world.
Most frequently ingested psychoactive substance.
Approximately 80% of caffeine consumed is in the form of coffee.
Common beverages coffee, tea, soft drinks, cocoa, chocolate containing foods, pain medications, and stimulants are important sources.
For typical servings caffeine content is highest in coffee, energy drinks, and caffeine tablets, intermediate in tea, and lowest in soft drinks.
Energy drinks contain between 70 and 200 mg of caffeine per 16 ounce serving.
An 8 ounce cup of coffee contains 110-150 mg for drip, 65-125 mg for percolated, and 40-80 mg for instant coffee.
Soft drinks contain 10-16 mg per 100 gm, coffee 35-75 mg per 100 gm and black tea contains about 22 mg per 100 gm.
Caffeinated beverages contain 50-100 mg of caffeine.
An ergogenic compound that raises heart rate and blood pressure.
Has short term cardiovascular effects, including increased plasma renin levels, peripheral vasoconstriction, increased blood pressure, and cardiacarrhythmias.
A bio-active ingredient found in commonly consumed beverages such as coffee, tea, and sodas.
Short-term physiological effects of caffeine include increased blood pressure and sympathetic nerve outflow.
Habitual consumption of caffeine may inhibit physiological short-term effects.
Consumption of caffeine increases parasympathetic activity in habitual caffeine consumers.
Capable of increasing work capacity while individuals perform strenuous tasks, likely due to caffeine’s ability to increase sympathetic nerve outflow.
Has tendency to inhibit parasympathetic activity in non-habitual consumers.
The effects on parasympathetic activity may vary depending on the position of the individual when autonomic responses are measured.
The seated position inhibits autonomic activity after caffeine consumption, explaining why some caffeine consumers do not experience short-term effects of caffeine if their routine requires many hours in a seated position.
Binds to the adenosine class of G protein coupled receptors on the heart muscle surface, which begins a second messenger system in the cyclic adenosine monophosphate system inside the cells and mimics epinephrine (Piirainen H at al).
Increases the rate of glycolysis, which increases ATP available for muscle contraction and relaxation and can cause positive Inotropy and chronotropy, with an associated stronger and faster heartbeat.
Exposure increases blood pressure and prayerful vascular resistance immediately, in part because of sympathetic stimulation.
May increase arterial stiffness.
May increase urine output.
No association between caffeine consumption and breast cancer risk (Ishitani).
Coffee intake is associated with a lower incidence of diabetes and favorable effects on the endothelial function.
Consumption associated with better mood in women (Kawachi I).
Inverse association between coffee drinking and depression and suicide.
Adverse effects manifest with ingestion with doses higher than 200 mg of caffeine and is associated with insomnia, nervousness, headache, tachycardia, arrhythmias, and nausea.
Meta-analyses show the consumption of caffeine does not demonstrate association with ventricular premature contractions or ventricular arrhythmias.
In a random clinical trial short term affects of high does caffeine in patients with heart failure at increased risk for arrhythmic events showed no significant effect on the frequency of ventricular or superventricular ectopies even doing physical stress or a treadmill test (Zuchinali P et al).
The above study challenges the perception that caffeine intake should be limited in patients with heart disease at risk for arrhythmia.
It is an effective ergogenic aid for endurance in athletes.
It is on the list of banned substances by the International Olympic Committee.
Oral absorption is rapid waves peak plasma concentrations after 29.8 minutes.
Mobilizes fat stores and stimulates muscles to use fat delaying depletion of muscle glycogen and allows for prolonged exercise (Laurent D et al).
Has essentially complete bioavailability with oral intake and a plasma half-life varying from 2.7-9.9 hours ( Blanchard J).
In a longitudinal study of 50,739 US women with a mean age of 63 years free of depression and followed, the depression risk decreased with increasing caffeinated coffee consumption (Lucas M et al).
One study found that the risk for type 2 diabetes decreased by 7% for each additional cup of caffeinated coffee consumed per day, and 6% per cup of decaffeinated coffee.
They found that a genetic predisposition to higher caffeine levels in the blood is linked to a lower risk for type 2 diabetes.
CYP1A2 and AHR genes slow down caffeine metabolism, meaning that for those carrying the variants, less coffee needs to be drunk in order to have elevated levels of caffeine in their blood, compared to those who metabolize it quickly.
Researchers also collected data on body fat, type 2 diabetes risk, and risk for cardiovascular conditions.
Genetically predicted higher blood levels of caffeine were linked to lower BMI, whole body fat mass, and type 2 diabetes risk.
It is suggested that 43% of the protective effect of blood levels of caffeine on type 2 diabetes came from weight loss.
Studies found no strong link between genetically predicted caffeine levels and cardiovascular conditions, including ischemic heart disease, heart failure, and stroke.
Higher caffeine intake increases thermogenesis, or heat production, in the body, and heat production increases calorie burn, and the ability to lose weight and fat.
Caffeine also inhibits overindulgence in eating by suppressing an individual’s appetite resulting in calorie deficiency which helps in preventing weight gain.
Higher blood levels of caffeine might lead to weight loss and reduce type 2 diabetes risk.
Too much caffeine can have significant harmful effects on health with regard to elevated blood pressure and poor sleep, and in patients who already have type 2 diabetes, caffeine can make their sugars worse.
Drinking coffee can affect cholesterol levels, although it may depend on the brewing method.
Unfiltered and French press coffee may raise cholesterol levels, while instant and filter coffee are less likely to affect them.
The risk of heightened serum cholesterol levels also depends on how much coffee a person drinks and how sensitive they are to caffeine.
Study results on the association between coffee drinking and higher levels of serum cholesterol are mixed.
One study on coffee consumption linked it to higher cholesterol levels, although the effects vary depending on the type of coffee and the sex of the individual.
It is not the amount of caffeine in coffee that may affect cholesterol levels but rather the oils that naturally occur in the coffee bean: natural oils, also known as diterpenes, are cafestol and kahweol.
Both oils can raise total and low-density lipoprotein (LDL) cholesterol levels.
The amount of diterpenes in coffee varies with the brewing method.
With coffee made using paper filters, most of the diterpenes remain in the filter.
With unfiltered coffee, more of the diterpenes pass through into the coffee.
Scandinavian boiled coffee, Turkish coffee, and French press coffee can increase cholesterol.
Espresso coffee has about half the amount of diterpenes found in unfiltered coffee, and has little effect on cholesterol.
Filtered coffee: It likely has little effect on cholesterol. However, research on this type of coffee is not consistent.
Instant coffee: This coffee type contains very few diterpenes, so it should not raise cholesterol.
Caffeine, as a psychoactive substance naturally occurring in coffee may interact with medications.
While the Food and Drug Administration (FDA) reports that 400 milligrams of caffeine per day is typically safe for health.
Caffeine may have various clinically significant interactions with many drugs.
Some other beverages, such as energy drinks, also have high levels of caffeine.
The Centers for Disease Control and Prevention (CDC)warns against mixing a caffeinated beverage, such as coffee, with alcohol, as the combination may result in a person drinking more alcohol than they realize and thus experiencing more of its harmful effects.
The amount of caffeine that the FDA considers safe is equivalent to four or five cups of coffee.
Some individuals are more sensitive to the effect of caffeine and may experience some of the following:
insomnia
fast heart rate
headaches
anxiety
jitters
nausea
a feeling of unhappiness
Other beverages containing caffeine include tea, sodas, and energy drinks.
Tea and sodas generally have less caffeine than coffee, while some energy drinks may have two to three as much caffeine as a coffee drink.
Coffee has several possible benefits, including:
lowering the risk of Parkinson’s disease, type 2 diabetes, and Alzheimer’s disease, helps protect cells from damage through its high levels of antioxidants, lowering the risk of death, reduces the risk of cardiovascular disease in women
Caffeine may:
increase energy
help with weight loss
improve mental focus
elevate mood
improve exercise performance
The diterpenes in coffee suppress the body’s production of substances involved in cholesterol breakdown, causing cholesterol to increase.
Coffee diterpenes may cause an increase in total cholesterol and LDL levels.
Paper filters may help minimize the amount of natural oils in coffee and result in a coffee drink with a lesser effect on cholesterol.