The more fitness articles you read, the more it appears that there's something you must cut out from your diet — carbohydrates, junk food, artificial sugar, etc. — for better results (in terms of performance and aesthetics) in the gym ❌
But here’s the thing: most of the advice you read? They’re complete BS.
In this article, we tear apart some of the most common, misguided beliefs on foods “bad” for your fitness journey, so you (finally) learn what matters and what doesn’t in your quest to achieve your fitness goals.
Think low-carb diets, like the ketogenic diet, would help you lose weight faster? Well, they could.
Note that this doesn’t mean you can’t achieve weight loss (then sustain it) with a low-carb diet. It simply means that you’re going to face difficulties sticking to the diet — which helps you stay within a set calorie budget — owing to its restrictive nature in the long run.
Psst: find out how to eat less without starving yourself here:
So, theoretically speaking, if you can stick to the low-carb diet for life, you needn’t worry. Right? Well, not so fast.
See, low-carbohydrate diets are also associated with the following:
- Initial fatigue: Many people report feeling weak and tired during the initial phase of a low-carbohydrate diet — and this has been observed to last anywhere from one to five weeks. Imaginably, this would set you back on your fitness journey (sometimes even before you’ve begun).
- Decreased performance: Remove carbs from the equation, and you likely won’t be able to lift as heavy or as many reps as you did before. And given that training volume is arguably the most significant predictor of hypertrophy, you see where this is going — leading us to the next point.
- Impaired muscle gains: Beyond the point above, there's another way the low-carb diet could hurt your gains. And that is: it suppresses your appetite, which means you may find it incredibly challenging to hit the calorie intake needed for optimal muscle growth — thus explaining research showing that non-ketogenic diets tend to lead to greater lean mass gains than a ketogenic diet.
You don’t have to avoid carbohydrates on your fitness journey ✨???✨
Doing so likely won’t yield better weight loss results (compared to any diet allowing you to achieve a calorie deficit); in fact, it may even hinder your progress in the gym.
2: Artificial sugar
Consuming artificial sugar would cause cravings for sugary foods — and, in turn, increase your calorie intake (good luck with your fitness journey then!) At least, that's what you'd typically learn from articles or hear from well-intentioned friends.
But guess what? They’re wrong.
On the contrary (and somewhat ironically), there’s even evidence that participants report less hunger — and consume fewer calories as a result — when they replace sugary foods and beverages with artificially sweetened alternatives.
Even better: various studies show that this may lead to a weight loss of up to 1.3 kg (2.9 pounds).
What about its adverse health effects? Research suggests that such worries are unfounded:
- Diabetes: Many controlled studies show that artificial sweeteners do not negatively affect blood sugar or insulin levels.
- Metabolic syndrome: Research consistently shows that the consumption of diet soda — which is often laced with artificial sweeteners — either has no effect or may even help protect against metabolic syndrome. To further elaborate on the latter, let’s look at this 2012 study published in The American Journal of Clinical Nutrition. Researchers had randomly assigned people with obesity to drink either 1 liter (a quarter gallon) of regular soda, water, or semi-skimmed milk each day. By the end of the six-month study, participants assigned the diet soda weighed 17-21% less, had 24-31% less belly fat, 32% lower cholesterol levels, and 10-15% lower blood pressure than those drinking regular soda.
- Cancer: Ah, yes — cancer. Thankfully, more than 30 human studies have failed to find a link between artificial sweeteners and the risk of developing cancer.
While artificial sweeteners could help you with your weight loss goals, simply swopping regular sugar out isn’t going to do all the heavy lifting for you.
There is still plenty of lifestyle and dietary tweaks you’ll have to make — more details below:
3: Soy protein
This one goes out to all the men believing that soy — thanks to its content of phytoestrogens — could reduce testosterone and, in turn, hurt muscle gains.
You'd have noticed a common theme running across this article if you've been paying attention (we're debunking myths!)
There are plenty of studies showing that soy protein is beneficial for hypertrophy. Take, for instance, this 2020 study. Researchers found that lean mass and strength increases in untrained participants are comparable when strength training and supplementing with soy or whey matched for leucine.
But wait — before you take the results at face value and think that soy protein (i.e., a plant-based protein) is just as effective as whey (i.e., an animal-derived protein), note the keywords "matched for leucine".
Ultimately, if you're on a vegan diet, you will have to be mindful of eating a variety of high-quality, plant-based protein sources to hit the leucine and overall protein requirement needed for optimal muscle growth.
Feeling lost? Don't worry. Check out our past article on maximizing muscle growth on a vegan diet for more guidance:
There's a ton of misinformation out there (e.g., on the Internet, written in magazines, and from hearsay) that can set you back on your fitness journey.
Good news: you don't have to be a victim.
If you're looking for a credible support system that'll help you achieve all your fitness goals, your search ends with GymStreak — an AI-powered personal trainer app that:
- Customizes your fitness plan to your unique needs (Can’t do an exercise? It’s out!)
- Links you up with like-minded fitness enthusiasts
- Provides science-based fitness information (e.g., this article)
Don't wait. Do it now.
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