Tea and coffee have been staples in our diet for centuries. Many of us consume it without a second thought, but have you ever considered the good and bad health effects of caffeine? Is there a value for athletes and gym-goers using caffeine as an ergogenic aid? Is too much coffee dangerous for your health? Finally, is there really any value to utilising caffeine as weight loss supplements? Read on to see what research-based science says about caffeine benefits & side effects!
How does caffeine work?
If you’re interested in getting an insight into the fascinating science around caffeine and how it keeps the droopy eyes at bay, read how does caffeine work. This link opens in a new tab and it’s a quick read which I guarantee you won’t regret!
Caffeine as a weight loss supplement: Many dieters consume weight loss and caffeine pills to lose weight, while other people rely on regular tea and coffee. Caffeine consumption leads to an increase anywhere from 3-11% in resting metabolic rate. The higher your metabolic rate is, the more calories your body burns. Unfortunately for obese people, the rate of fat burning that occurs based on metabolic rate is lower than for a lean person. A study observed fat burning rates of up to 29% in lean people, while only a 10% increase in fat burning was observed in obese people.
There is, however, a clause that needs to be highlighted. The body over time can become accustomed to regular caffeine consumption. Consequently, the increased metabolic rate and associated fat burning effects can diminish over long periods of time. You can reduce this tolerance by engaging in caffeine cycling which involves periods of abstaining from caffeine altogether, e.g. 2 weeks no caffeine followed by 2 weeks consuming caffeine.
Saying that, all hope is not lost as caffeine has been shown to suppress appetite. So whenever you feel like grabbing the nearby bar of chocolate or diving into the fridge, first opt for a cup of tea or coffee.
Caffeine and exercise: Anyone with a keen interest in sports and working out will likely consume caffeine as a pre-workout supplement. This is why it makes my top 5 bodybuilding supplements. Many people often consume a pre-workout caffeine supplement to enhance their performance. If you’re interested in reading about caffeine pills and other caffeine supplements, check out do healthy caffeine supplements exist?
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Caffeine has been proven to decrease rates of perceived exertion, making the workout feel somewhat easier. Additionally, since caffeine reduces fatigue, the number of reps and power output is elevated, meaning you can exert extra reps when compared with no caffeine ergogenic aid. A study observed an increase of 11.60% reps on the bench press and 19.10% when completing leg presses, which is rather impressive, especially when nearing failure!
Caffeine and feeling good: If you took the time to read how does caffeine work, you’ll know that caffeine aids in releasing dopamine, also known as they feel-good chemical. So if you experience elevated feelings of joy after drinking your caffeine beverage (or food) of choice, you now know why! As a result of this dopamine release, evidence has suggested that caffeine consumption may reduce the rates of suicide when 2-4 cups of coffee are consumed daily.
Miscellaneous caffeine benefits:
- A meta analysis study has identified positive protective effects from liver cancer.
- A separate meta analysis study concluded that reduced risk of death from all causes was observed in people who consumed 2-4 cups of coffee a day.
- Other studies suggest that caffeine may offer protection against type 2 diabetes, Parkinson’s disease and strokes
Caffeine adverse effects
The recommended daily limit dose of caffeine is 400 mg. Exceeding this recommended value is typically where the bad health effects of caffeine are observed. Want to know are you consuming too much caffeine? Check out what does 400 mg of caffeine consumption look like?
Caffeine addiction and withdrawal: With all the above benefits of caffeine, it’s not surprising that caffeine is highly addictive. Sometimes people don’t realise that caffeine is a psychoactive drug, meaning it increases activity in the central nervous system, namely the brain. These effects are in fact similar to the effects observed following cocaine consumption! With this elevated alertness follows feelings of increased productivity. Caffeine also releases dopamine making us feel good, which is another factor which contributes to the addictiveness of this stimulant.
Caffeine withdrawal can lead to a range of symptoms, including:
- Low mood
Insomnia: We are all now aware of the value caffeine has in terms of reducing fatigue and increasing alertness. With this in mind, it’s no wonder that many people experience difficulties sleeping. Caffeine has a half-life of anywhere from 5-8 hours depending on the caffeine dose and individual factors such as caffeine tolerance, weight and pregnancy. This means traces of the stimulant could remain in your system when you’re trying to sleep, even if your last caffeine consumption was earlier in the day.
Anxiety: The effect of caffeine on anxiety symptoms can be attributed to elevated feelings of alertness arising from increased adrenaline release. This fight or flight response can be increasingly pronounced in individuals and result in increased nervousness and anxiety. One study observed a greater than twofold increase in stress amongst male participants who consumed a 300 mg serving of caffeine (equivalent to approximately 2 cups of coffee). Surprisingly, these effects prevailed in both light and habitual caffeine consumers.
Muscle breakdown: Negative health effects of caffeine in terms of reduced muscle growth have been observed in people where excess caffeine is consumed. This condition, known as rhabdomyolysis, causes damaged muscle fibres to enter the blood stream. While the cases attributed to excess caffeine consumption are relatively rare, some instances have been observed, e.g. in a 21-year-old male who consumed 450 mg caffeine (approximately 3 large cups of coffee) 30 minutes before exercise.
Miscellaneous caffeine adverse effects:
- High caffeine consumption has been linked to a temporary elevated blood pressure, which would be a concern for individuals currently diagnosed with high blood pressure.
- Caffeine consumption has also demonstrated elevated heart rates in some people and can also lead to an irregular heart beat, known asatrial fibrillation. This condition has been observed in young individuals who consume energy drinks which typically have a very high caffeine content.
- With an increase in alertness and energy comes an inevitable feeling of fatigue for many people once the caffeine leaves their body. While this could be counteracted by maintaining caffeine in your system throughout the day, this could ultimately result in disrupted sleep and consequently feeling tired.
- When consumed in moderation, caffeine can provide some excellent health benefits
- Caffeine is an excellent ergogenic aid to enhance performance during exercise
- People using caffeine for weight loss/fat burning may only see short-term benefits as their body becomes used to caffeine
- Excess caffeine can cause insomnia, fatigue, elevated heart rate and lead to addiction
- Caffeine cycling and adhering to the daily caffeine dose limit of 400 mg can minimise negative health effects of caffeine
What’s your opinion on caffeine? Do you think the benefits outweigh the disadvantages? Have you ever felt addicted to caffeine or do you frequently opt for the decaf beverages? I’d love to hear your opinion in the comments below!
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