The Science of Caffeine

Image is Courtesy of The Guilfordian

Caffeine is consumed by people everywhere, known as the world’s most popular drug. In North America, more than 80 percent of adults regularly consume caffeine. In Canada, it is estimated that the average amount of caffeine consumed per person a day is 210- 238 mg. It is most commonly found in coffee, black, and green tea and can be additionally found in energy and soft drinks. Some chocolate bars, energy bars, and non-prescription medications like cough syrup and slimming tablets may also contain caffeine.

What Is Caffeine?

Caffeine is associated with keeping the body awake. It is a natural central nervous system stimulant that keeps you alert and prevents the onset of tiredness. Caffeine is a psychoactive drug. According to the National Cancer Institute, psychoactive drugs affect how the brain works and may change the body’s mood, thoughts, behaviour, or feelings. Some other examples of psychoactive substances include marijuana, cocaine, LSD, heroin, and amphetamines. However, unlike other psychoactive drugs, caffeine is legal and unregulated across many countries in the world.

Caffeine is a methylxanthine alkaloid. PubChem states that in its pure form, it is a white, bitter-tasting powder. It can be found in seeds, nuts, or leaves found in South America or East Asia. Although commonly ingested by mouth, it can also be used rectally with painkillers to treat migraines.

Caffeine's Molecular Structure.

Image is Courtesy of PubChem

The typical amounts of caffeine in common products:

• One cup of brewed coffee: 135 mg

• One cup of tea: 43 mg

• One can of regular cola: 36-50 mg

• One can of energy drink: 80 mg

• Dark chocolate (28 g): 19 mg

• Milk chocolate (28 g): 7 mg

• Packet of hot chocolate mix: 7 mg

How Does Caffeine Work?

Once caffeine is consumed, it is absorbed from the gut into the bloodstream. It then travels to the liver and is broken down into compounds. According to Healthline, caffeine blocks the effects of adenosine, a neurotransmitter that relaxes your brain and makes you tired. Regularly, adenosine levels build up, making you more tired and causing you to want to sleep. Caffeine helps you stay awake by connecting to your adenosine receptors, therefore leading to reduced tiredness.

Caffeine may increase blood adrenaline levels and increase the brain activity of the neurotransmitters dopamine and norepinephrine. This further promotes a state of arousal and focus. In beverage form, caffeine can begin to take effect within five minutes, reaching a peak at 30 minutes.

How caffeine works.The Tartan

How Does It Affect Your Body?

Other than increased alertness, caffeine can also increase breathing and heart rate. Depending on the individual, effects may last up to 12 hours. Scientists suggest that 400 mg is an acceptable dose of caffeine per day. According to BetterHealth, having too much caffeine may result in some of the following symptoms:

• Frequent urination

• Dehydration

• Sleeplessness

• Rapid heartbeat

• Anxiety and irritability

High doses of caffeine can additionally cause a diuretic effect. These doses include between 250-300 mg, which is equivalent to around two to three cups of coffee. Diuretics are substances that cause the body to increase its urine output. This is due to an increase in blood flow to the kidneys, resulting in them releasing more water through urine.

Possible effects of caffeine in the long term and short term. Positive Choices

How Does It Affect Your Mood and Brain Function?

In a study done by the Department of Nutrition, Harvard School of Public Health, drinking 2-3 cups of caffeinated coffee per day led to a 45% lower risk of suicide. Not only this, but another study showed a 13% lower risk of depression in caffeine consumers. However, an increased amount of caffeine consumption does not linearly correlate with a boosted mood. Another study shows that a second cup of coffee has no effect unless consumed 8 hours after the first cup.

Does Coffee Boost Metabolism or Burn Fat?

Since caffeine increases the body’s levels of epinephrine or adrenaline, Healthline says it can help mobilize fat from the tissue. Adrenaline travels through the blood to the fat tissues, sending signals to break down fat and release them into the blood. However, fatty acids in the blood will not increase fat loss unless a negative energy balance (burning more calories than consumed) is achieved. Coffee can additionally increase the body’s metabolic rate. If you have a higher metabolic rate, it is easier to lose weight. Studies show that consuming caffeine is able to increase the metabolic rate by 3-11%. These effects are more prevalent in younger individuals and are less pronounced in those with obesity.

With an increased amount of caffeine consumption over a long period of time, many people develop a tolerance. While in the short term, caffeine can boost metabolism, people become tolerant to the effects of caffeine in the long term. At this time, there is no evidence suggesting that caffeine helps individuals lose weight in the long term.

Caffeine Tolerance and Demand Dependency

Over time, many people become physically and psychologically dependent on caffeine to function. Withdrawing from caffeine may cause symptoms such as fatigue, crankiness, persistent headache, and muscle pain. If you are experiencing caffeine withdrawal, the best option is to gradually reduce your coffee intake so that your nervous system has time to adapt without the drug.

Is Coffee Bad for You?

Benefits of coffee.Lee's Fitness Unlimited

Not only does coffee keep you alert, but according to Medical News Today, it also contains many nutrients, such as riboflavin, niacin, magnesium, potassium, and antioxidants. It is suggested that coffee provides many benefits including:

• Protecting against type 2 diabetes

• Protect against Parkinson’s disease

• Lower the risk of liver cancer by 40%

• Protect against heart failure

Some myths exist, such as the notion that coffee stunts growth. This is not true, as how tall you mostly depend on your genes. The real potential risks of coffee may include temporarily raised blood pressure, but this should not be an issue unless heartburn, nervousness, or insomnia begin to take effect.

Article Author: Jennifer Law

Article Editors: Edie Whittington, Stephanie Sahadeo