Supplement and nutrition myths have always been around – but these days they spread faster thanks to viral content that can leave you wondering whether supplements actually work.
The problem is knowing what’s a supplement myth and what’s fact. So let’s fact-check eight of the most common nutrition and gym myths that are still circulating.
Myth 1: Protein damages your kidneys
We’re starting with one of the oldest protein myths – your nan might even have said this to you the first time she caught you with a protein shake. Does protein damage your kidneys?
Verdict: Current research consistently shows that protein supplements or a higher protein intake do not damage healthy kidneys.
Protein does increase the amount of work your kidneys do, just as lifting weights makes your muscles work harder, but that’s a normal physiological response.
The key distinction is healthy kidneys. If you have diagnosed kidney disease or reduced kidney function, you should discuss your protein intake with your doctor or nephrology specialist.
Myth 2: You have to eat protein within 30 minutes of training
The famous anabolic-window myth suggests that you need to get a protein shake down as quickly as possible after training – and certainly no more than 30 minutes later.
Verdict: The window is much wider than 30 minutes.
Muscle protein synthesis, or MPS, stays elevated for hours after resistance training – and that’s not the only fact that challenges this myth. Your total daily protein intake has a bigger impact than whether you have a protein shake immediately in the gym changing room.
That doesn’t mean post-workout nutrition isn’t useful. Eating protein after training is a sensible habit, and a protein shake can be a convenient option, but it doesn’t need to become a race against the clock.
Myth 3: You can only absorb 30g of protein per meal
If you search online for whether you can only absorb 30g of protein at once, you’ll find plenty of confident answers. But is it actually true?
Verdict: This is an oversimplification of the science.
Your digestive system absorbs nearly all the protein you eat. What changes is how that protein is used. For most people, muscle protein synthesis appears to plateau after a certain amount in a single meal, but additional protein isn’t simply wasted. Your body can use those amino acids for other tissues, enzymes, hormones and energy.
Rather than worrying about hitting an exact number at each meal, most people would benefit from spreading their daily protein intake more evenly across the day.
Myth 4: Detox teas and pills flush toxins out of your body
The idea sounds great – drink a tea or take a capsule and cleanse your system of toxins, although the myth is rarely specific about which toxins it means.
Verdict: Your body already has its own detoxification systems.
When people ask whether detox teas or detox supplements remove toxins, the important point is that your liver, kidneys and digestive system already perform those functions.
Some detox products may contain ingredients that increase bowel movements or water loss. That can create the impression that something dramatic is happening, but it isn’t the same as removing toxins from the body.
If your liver or kidneys aren’t functioning properly, detox teas aren’t the answer – medical investigation and appropriate treatment are.
Myth 5: In supplements, natural means safe
It’s easy to assume that if something comes from a plant, it must be harmless.
Verdict: Natural doesn’t automatically mean safe.
Lots of medicines are plant-derived, and natural substances can still interact with medications or cause unwanted side effects. Something being natural doesn’t mean it shouldn’t be scrutinised.
That’s why it’s worth checking ingredient lists, following recommended serving sizes and speaking to a healthcare professional if you’re pregnant or breastfeeding, have a medical condition or take prescription medication.
Myth 6: Fat burners melt body fat
People will always look for ways to lose weight, so it’s no surprise that questions about whether fat burners work continue to circulate.
Verdict: Not in the way the marketing often suggests.
Many legal fat-burner supplements contain ingredients such as caffeine or plant extracts that may slightly increase energy expenditure or help people feel more alert during training.
What fat burners don’t do is simply melt body fat away. Fat loss comes down to maintaining an appropriate calorie deficit over time alongside training and lifestyle habits you can sustain.
Myth 7: BCAAs are essential if you already eat enough protein
Branched-chain amino acids, or BCAAs, used to be among the most popular gym supplements on the market. But are BCAAs necessary?
Verdict: If you already eat enough high-quality protein, BCAAs usually aren’t necessary.
BCAAs provide three essential amino acids – leucine, isoleucine and valine – while complete protein sources provide all nine essential amino acids. So if your daily protein intake is already sufficient, you’re likely getting those BCAAs from your diet.
This is why many people now prioritise meeting their overall protein target before thinking about supplementing with additional amino acids.
Myth 8: More protein always means more muscle
Protein is important, but more doesn’t magically turn into more muscle.
Verdict: Muscle growth has limits.
Once you’re consistently eating enough protein to support your training goals, dramatically increasing your intake won’t necessarily speed up your gains.
Other factors matter just as much, if not more – including progressive overload, recovery, sleep, training quality and total calorie intake. Protein supports the process, but it isn’t the only ingredient involved in building muscle.
How to spot supplement and nutrition myths
The supplement industry isn’t short of big claims, which is why it’s worth asking questions before believing a viral video or pressing the buy-now button.
Many supplements have evidence behind them when they’re used for the right reasons. Others promise more than the research currently supports. The trick is separating realistic expectations from clever marketing.
A few useful questions to ask:
- Does the claim sound too good to be true?
- Is the product clear about what’s actually in it?
- Are ingredient amounts transparently listed?
- Is the claim realistic for the role of a supplement?
- Could the basics of nutrition, training or recovery matter more?
The basics still work best: train well, eat a balanced diet, recover properly and use supplements to fill genuine gaps rather than replace the foundations.
If you’re building a supplement routine, focus on products with transparent ingredients and a clear intended purpose. You’ll find those principles across the Per4m supplements range.
