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What is Caffeine?
Did you know that caffeine is considered a psychoactive drug?
Caffeine is a powerful stimulant found naturally in plants such as coffee beans, tea leaves, and cocoa beans.
Humans around the world have been drinking coffee and tea for thousands of years. Currently, coffee is the most frequently consumed beverage all over the world (asides from water). The average American consumes about 2 cups of coffee a day.
It can also be found in other forms, like in energy drinks, soft drinks, and supplements.
How Does Caffeine Work to Affect Wakefulness?
It is common knowledge that caffeine can give us a boost of energy when we are feeling fatigued or didn’t have a good night’s sleep. But what exactly is caffeine doing in our bodies?
Throughout the day, your levels of adenosine rise. Adenosine and caffeine molecules look very similar. When you ingest caffeine, it competes with adenosine for adenosine receptors.
Once caffeine binds to these receptors, it won’t activate the adenosine receptors since caffeine isn’t identical to adenosine. But this action prevents adenosine from activating the receptors.
So instead of feeling tired as the day progresses, it can increase alertness and combat fatigue.
In addition, neurons begin to fire rapidly which directs the pituitary gland to release hormones. This hormonal release signals the adrenal glands to produce adrenaline.
Part of this bodily response includes blood vessel constriction, decreased ability to feel pain, an increase in strength, and heightened awareness. Evolutionary speaking, these responses used to come in handy when our lives were at risk.
However, when you are sipping a latte in a local cafe on your coffee break, you aren’t generally under physical attack. Therefore, you may experience other effects such as light-headedness, restlessness, nervousness, insomnia, and, over time, even heart damage.
What Are The Evidence-Based Health Benefits of Caffeine?
Caffeine consumption has been associated with a lower risk of developing:
- Alzheimer’s disease
- Parkinson’s disease
- Cirrhosis of the liver
- Liver cancer
- Colon cancer
- Erectile dysfunction
Can Caffeine Support Weight Loss?
Some evidence shows it can act as a thermogenic (increases heat production) which could aid weight loss. In addition, when taken before exercise, caffeine may help release stored fat.
However, relying on caffeine alone to achieve your weight loss goals is not advisable.
There are much safer and more sustainable ways to lose weight. This can look like eating a whole food plant-based diet, regular physical activity, stress management and reduction, and quality sleep.
Does Caffeine Improve Cognitive Performance?
Can Caffeine Improve Physical Performance?
Caffeine is commonly added to energy drinks and pre-workout supplements. The reason for this is caffeine may provide increased anaerobic and aerobic capacity possibly due to its ability to combat fatigue.
Endurance athletes, such as cyclists, may perform better when using high doses of caffeine than even carbohydrates or water. Although, the combination of carbohydrates and caffeine may have an even greater effect.
Other research supports its use in weightlifting as caffeine appears to increase power output.
However, the impact on athletic performance may change based on your level of athletics. It seems that the beneficial effects of caffeine generally only occur in highly trained individuals but not as much in untrained individuals.
How Does Caffeine Affect Stress?
In times of high stress, like with a work deadline approaching, you may be tempted to chug a cup of coffee to complete the task. However, caffeine consumption triggers the release of cortisol and adrenocorticotropin (which regulates cortisol).
So, perhaps an alternative with less caffeine, like tea, maybe smarter during times of high stress for your long-term health.
Will Caffeine Affect My Sleep?
Since caffeine increases wakefulness, it makes sense that it would have an impact on your ability to fall asleep. You should keep in mind that the half-life of caffeine is about 5-6 hours. This means it will take 5-6 hours to eliminate just half of the caffeine you ingested.
Other considerations to account for which will affect caffeine’s half-life include your age, body weight, what medications you’re using, whether you are pregnant, and the health of your detoxification organs.
Therefore, a late afternoon cup of coffee may affect you still when it is time to go to sleep.
Caffeine may also negatively impact your quality of sleep.
It is advisable to avoid caffeine in the afternoon or evening in order to get a full night’s rest.
How Much Caffeine Should You Take?
An 8-ounce cup of coffee contains about 80-100 mg of caffeine while a cup of black, white, or green tea contains between 14-61 mg (FDA). However, the amount of caffeine can vary depending on the type of coffee, how it is brewed, and how long it is brewed.
Supplements are available as well which are generally at higher doses. However, you may miss out on the antioxidants in a cup of coffee if taking the isolated caffeine anhydrous instead.
Energy drinks are popular, especially among youth. They contain very high doses of both caffeine and sugar. Therefore, energy drinks have been associated with harmful side-effects, including cardiovascular risks.
Possible Side Effects and What to Be Aware Of
Over time, you will become tolerant to the effects of caffeine. The benefits of caffeine also become reduced. Therefore, people often find they need to increase caffeine intake to have the same desired effect as previously. This can lead to caffeine dependence.
You may even experience withdrawal symptoms like headaches, irritability, and sleepiness when you don’t consume caffeine.
Since caffeine is a stimulant, consumption may be dangerous for those with high blood pressure or other cardiovascular health concerns.
Caffeine causes vasoconstriction, which is where your blood vessels narrow, and blood flow is restricted. It can also increase heart rate, particularly in high doses and for those with low tolerance.
For people with diabetes or pre-diabetes, the effect of caffeine is unclear. Caffeine doesn’t appear to affect fasting insulin levels (either positively or negatively), however, blood sugar levels can rise after caffeine consumption.
In addition, it may decrease insulin sensitivity, particularly when ingested with carbohydrates.
Some medications can enhance the effect of caffeine. For example, the oral contraceptive pill can double the half-life of caffeine. This means that the morning cup of joy may hit you harder and longer if you are on the birth control pill.
During pregnancy, the half-life of caffeine is also extended. The caffeine can transfer to the fetus potentially affecting development which is why caffeine during pregnancy is cautioned. The exact amount advised during pregnancy is a good conversation to have with your medical provider.
Likewise, children should avoid caffeine as the effects on development are still unknown.
Some people notice increased anxiety after ingesting caffeine. Therefore, caffeine may not be a good idea if you have experienced panic attacks or anxiety disorders.
Research shows that genetic variants may be responsible for the link between anxiety prompted by caffeine consumption and experiencing panic attacks. This would explain why some people don’t experience increased anxiety with caffeine, while others witness a notable effect.
Caffeine consumption, in low to moderate doses, seems to be safe for most individuals. It may even be beneficial in preventing long-term diseases related to cognitive decline, and even various cancers.
Before exercise may be the most beneficial time to reap extra benefits physically. However, the time of day matters.
You may want to experiment with the timing of your tea and coffee consumption. If you have trouble falling asleep, it can help to take note of how late you are consuming coffee, tea, or chocolate. Setting a cut-off time can be helpful in managing caffeine consumption and sleep.
There are cautions to be made for certain groups, as outlined previously. In addition, developing a dependency is common and should be avoided.
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