Should Lifter's be worried about Caffeine? A Dietitian weighs in on its benefits and possible risks.

Picture this: You wake up, and have your usual cup of coffee. Then later in the day you go out with your friends and grab an iced coffee. Then before your workout, you have a scoop of pre-workout. Maybe you also have a Coke Zero or Mountain Dew during the day.

Why does this matter? All of these beverages contain caffeine, and over the course of a day, our intake can add up quite a bit.

"I've heard that caffeine can boost athletic performance"

"I've heard that caffeine can boost your metabolism and help with weight loss. Is this true?"

With all the information available, it can be hard to understand what's fact, and what's fiction. So today I am going to break it down for you!

What is Caffeine, and how does it work?

Caffeine is a central nervous system stimulant. It acts as an adenosine receptor antagonist. Adenosine is a compound that helps us sleep. Normally when adenosine binds to its receptors, neural activity slows down and we get more sleepy. However, because caffeine has a similar structure to adenosine, it can bind to its receptors WITHOUT activating them. As a result, people are often more alert and less sleepy after having a caffeinated food or beverage!

KEY point here is that caffeine is a STIMULANT therefore it provides us with stimulation, but it does not provide us with energy. Remember: Our body gets energy from foods containing carbohydrates, protein and fats - the energy (Calorie) yielding macronutrients.

Benefits vs Risks of Caffeine

BENEFITS

• May decrease perceived exertion during resistance training allowing athletes to lift stronger, and for longer

• May decrease perception of fatigue which can enhance strength and endurance performance

• May improve focus, concentration and coordination

RISKS

• Consuming too much caffeine (over 6 mg per kg body weight) can lead to side effects including overstimulation, jitters, gastrointestinal issues including diarrhea and nausea. Caffeine tolerance is unique between individuals. Some may be able to tolerate higher amounts, while others may only be able to tolerate small amounts.

• May impair sleep, even if having 6 hours prior to bedtime

• Withdrawl symptoms can occur if someone becomes dependent on it, especially at high doses

• If you're an athlete who competes at drug tested events, caffeinated supplements such as pre-workout may not be third party tested. Taking these supplements may increase the risk of unintentional doping- see more on this below
  

Considerations for Caffeine use and sports performance:

Quantity, and timing

• The International Society of Sports Nutrition (ISSN) summarized that 3 - 6 mg Caffeine within 60 minutes prior to training has been shown to improve performance

• Performance enhancing effects may last up to 4 hours

• Use caution if having in late afternoon or evening as it may reduce duration and quality of sleep- which is a key component of recovery

Awareness

• For certain products such as gels and bars, the caffeine content will be listed on the package. However, for other items such as brewed coffee, the caffeine content may vary considerably.

• It is important to be aware how much caffeine you're already consuming thoughout the day (see below near end of article for list of foods and beverages)

Third Party Testing

• If you are an athlete who competes at the competitve level in drug tested events including in collegiate/varsity, national and/or international level, it is strongly encouraged for you to ensure that your supplements are Third Party Tested (examples include: NSF and Informed Sport)

• This is to prevent unintentional doping - which occurs when an athlete unknowingly tests positive for a banned substance. Supplements are not regulated in the same manner as food items are (ex: Coffee, tea, chocolate etc). So if competing at a drug tested event and want to use a caffeine/caffeine containing supplement such as pre-workout, it is best to ensure that your product is third party tested. For example Cellucor C4 is a Third Party Tested pre-workout available in Canada.

• Caffeine is not prohibited by WADA (World Anti Doping Agency), though certain federations may have additional restrictions with the use of caffeine.

Does caffeine impact weight loss?

Weight loss is influenced by our total energy balance. Simply put, we must be in a calorie deficit in order to experience weight loss. This means our calories IN (energy intake through food) must be less than our calories OUT (ex: physical activity).

A 2018 systematic review finds that caffeine consumption might reduce BMI, body fat, and overall weight.  Some evidence suggests that caffeine may increase our metabolic rate (in other words, increases the "calories out"), however this effect is very mild, short-lasting and may weaken as our tolerance develops. Relying on caffeine alone to lose weight will likely yield dissapointing results. HOW you consume your caffeine is also important. For instance, an iced coffee from a café with loads of syrup and cream is likely high in Calories, which will not aid in weight loss. If weight loss is a goal, focus on your total energy (Calorie) intake, consume an adequate amount of protein, carbohydrates and fats, and incorporate strength training and cardio into your routine.

Where is caffeine found in?

Caffeine is found in various foods and beverages. Take a peek at the list below - look at how much you might be consuming throughout the day!

The Low Down - should you be concerned about caffeine?

A safe amount of caffeine can may have benefits including improving your focus, concentration and performance. This should not be of concern for most.

But, if you're consuming large amounts of caffeine, and are finding that you're dependent on it in order to train or to be productive overall, then this may lead to concerns.

Having too much caffeine (over 6 mg per kg body weight) can lead to side effects and extremely high doses can be fatal.

So no, most healthy people do not need to be concerned about caffeine. As long as you are aware of your tolerance, aware of around how much you're consuming, and are responsible with your intake, caffeine can be super helpful in boosting your performance!

Caffeine and eating to train better at the gym are frequent topics of discussion with many clients I see. I encourage you to sign up today to learn how to fuel yourself properly. I currently have open spots available and would love to help you reach your goals!

Please note that the content provided in this blog post is for informational and educational purposes only. It is not intended to substitute professional medical advice, diagnosis or treatment