This article will provide a research-backed answer to your question, “does pre-workout suppress appetite”?
Have you noticed a dump in your cravings after your workouts, and you suspect pre-workout to be the reason? You may be rightly skeptical about the potential of pre-workouts to curb your appetite.
Pre-workouts are designed to enhance your workout outcome, which calls for ingredients that increase energy and promote weight maintenance.
And caffeine is believed to be the best ingredient that may serve all your needs.
In addition to it, manufacturers also stuff their products with muscle-building proteins to aid recovery. But these ingredients might also be the reason why you have been avoiding food lately.
For this article, I have looked into the pre-workout components to determine their impact on appetite, hunger, weight gain, and weight loss.
How Does Pre-workout Affect Appetite?
You can rightly blame pre-workouts when even your favorite mac and cheese seems less appetizing to you when you are starving after your training.
The reason is that pre-workout ingredients may be working behind the scene to suppress your appetite.
Most pre-workouts contain a high content of caffeine to promote mental focus and increase energy levels. But this high caffeine content may be the culprit behind your reduced appetite.
According to this 2017 review, caffeine may influence the brain regions that control appetite and feeding. Moreover, consuming caffeine 30 minutes to 4-hours before laying your table may suppress acute energy intake from macronutrients.
Another pre-workout component that you may blame is Branched Chain Amino Acids (BCAAs).
BCAAs are the three essential amino acids, leucine, isoleucine, and valine that manufacturers add to pre-workouts mostly in the ratio of 2:1:1 because of their potential to stimulate protein synthesis.
BCAAs promote muscle recovery, increase lean muscle and suppress appetite as well.
This 2014 research reported that a leucine content, even if it is as low as 10μg, may reduce food intake in the subjects. It may influence the neurons and signaling systems that impact the feeding behavior to bring this effect.
Can Pre-workout stop weight loss?
No, in fact, the different ingredients in pre-workouts may help you lose some extra lbs.
Some NIH-listed weight-loss ingredients manufacturers use in pre-workouts are caffeine, bitter orange, glucomannan, capsaicin, carnitine, Coleus forskholii, coffee bean extract, guar gum, and Yohimbine.
These ingredients exert their weight loss effect by accelerating thermogenesis and metabolism, reducing the absorption of macronutrients, increasing satiety, or suppressing appetite.
For instance, caffeine, the primary ingredient in pre-workout, has a thermic effect and contributes to weight maintenance. It also reduces the absorption of glucose and lipids, which contributes to weight loss.
This review reported that capsaicin reduces protein and fat intake and increases thermogenesis to show its anti-obesity potential.
Guar gum is another ingredient that increases the feeling of satiety that aids your weight loss by keeping you from thinking about food for longer.
Does pre-workout make you fat?
No, pre-workouts won’t cause you to bulge out. But instead, its different ingredients can promote fat loss.
For instance, Yohimbine is a pre-workout ingredient that counters your fear of gaining fat by promoting weight loss.
According to this 2013 study, this traditional herb effectively facilitates fat loss in athletes.
Let me go into a bit more detail so that you can understand the phenomenon easily.
You take pre-workouts to improve your exercise performance, and exercising itself is beneficial in reducing fat.
It does this by elevating the levels of catecholamines in the blood. But when you supplement your exercise with a yohimbine-containing pre-workout drink, it enhances the effect of catecholamines on lipolysis by inhibiting something called alpha 2 receptors, thereby ‘not making you fat.’
But before I move over to the next section, let me clear out suspicions regarding BCAAs.
You might have come across this 2022 publication in which Filipino women consumed 10.3g per day of BCCA for three years from 2014 to 2016, and it was reported to contribute to obesity in them.
But in contrast to this, pre-workouts provide a daily dose of only 2-5 grams BCCA, and they are supposed to be consumed for less than eight weeks since there are no safety studies after it, and they start to lose their effect as your body adapts to the stimulants.
Do you still think they will make you fat? I hope not.
The other most common ingredient, creatine, might also be a cause of concern for you because of its potential to increase lean muscle mass.
But rest assured that a gain in lean muscle mass may not equate to a gain in fat. But you always have the choice of picking up a creatine-free pre-workout on your next grocery trip to remove the place of any doubts.
Does pre-workout make you hungry?
Pre-workouts do not directly affect your hunger.
They are typically formulated to promote weight loss, so there is a slight possibility that manufacturers would add any ingredients that may stimulate your hunger.
You might be getting those hunger pangs from excessive weightlifting, but the high dose of caffeine from the pre-workout you gulped in might affect your response to this hunger.
‘Brandonkohl’ also mentioned in this Reddit thread that along with helping him push harder in the gym, his pre-workout also suppresses his appetite.
The user response on this thread mutually agrees that caffeine is the root cause of the reduced appetite.
You can understand this phenomenon from this 2014 clinical trial, according to in which caffeine increases satiety and fullness and reduces food consumption afterward, but it has no effect on hunger.
To conclude, yes, pre-workouts may suppress your appetite.
Caffeine is the main reason why you feel a reduction in your appetite after drinking a pre-workout drink since it influences the appetite hormones and delays stomach emptying, which makes you want to eat less.
Nonetheless, in addition to pre-workouts, exercising may also decrease your appetite as it alters the release of the appetite hormones, which changes your response to food cues.
If you find it hard to meet your calorie requirement after a pre-workout but still want to consume them to enhance your workout performance, try shifting to a non-caffeine alternative that uses other ingredients to give you the energy boost you need.