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The Most Common Diet & Fat Loss Nutrition Myths Debunked


Trying to lose weight, but keep reading contrasting advice? In just one day on the internet, you might read that fruit is bad for you, but you should only eat fruit if you want to lose weight… Or that eggs give you high cholesterol, but eggs are the best source of protein and you should eat them everyday. There are hundreds if not thousands of nutrition myths floating around, which makes it hard to know just what to eat and what to avoid if you want to make healthy food decisions.

In this blog, Personal Trainer Josh Ginelly who is based at our Leeds City Centre North gym debunks some common diet myths to help make your fat loss journey easier.

“Over the years I’ve seen and heard some crazy stuff relating to what and how people should be eating if they want to achieve fat loss, I’ve even made a lot of mistakes myself. And whilst there may not be a blanket prescription for losing body fat or a one-solution-fits-all approach, it does help to be aware of the common pitfalls that so many of us fall victim to.”

The Most Common Fat Loss Myths I Get Asked About As A Personal Trainer

Myth 1: Does Cutting Carbs Help Lose Weight?

Over the last decade, we’ve moved away from a fat-fearing society to one which points the finger at carbs as the cause for weight issues. Some of these claims are centred around the idea that carbs cause an insulin spike, and as insulin is the ‘fat storage hormone’, eating carbs causes the body to store fat. While this makes sense on paper, there have been studies comparing low carbohydrate diets vs diets where carbs are not restricted, and eating carbs haven’t been found to hinder weight loss goals.

In one 2015 study, participants were split into 2 groups (low fat and low carb) and were  prescribed diets to keep them in a calorie deficit (when your energy output is higher than your energy input). After 8 weeks of the diet, both groups reported an equal drop in fat loss. What this study shows is that being in a calorie deficit is what results in fat loss. 

So people who cut out carbs and lose weight do so, not because there is anything inherently bad about carbs, but simply because they are restricting themselves from consuming an entire food group. By eating less of a food group which they would have usually been eating, their chances of eating fewer calories naturally would be lower.

In summary: 

To wrap this myth up, it is calories not carbs that really matter when it comes to fat loss.

Choose a dietary strategy that allows you to achieve your goals and sustain it in the long run. Most people find allowing all food groups in moderation is the most sustainable approach to dieting.

You can learn more about calories and what they mean for weight loss here.

Myth 2: Do Fat Burner Supplements Work To Speed Up Weight Loss?

Before we drive into whether fat burners work or not, let’s look at what they claim to do. While the exact claims can vary between products, you’ll typically find they say they will:

  • Suppress your appetite so you don’t eat as much
  • Boost your metabolism

Fat burners are not magical supplements. While they can help to suppress appetite and give an energy boost, any supplement with a high amount of caffeine in can do the same. You can easily replicate the desired effects of fat burners in a more sustainable way by eating enough protein throughout the day, and drinking the occasional coffee.

Taking fat burners does not improve your relationship with food and relying on high amounts of caffeine can negatively impact sleep, which can actually slow down your weight loss. They’re also unregulated, and may have ineffective ingredients in there at best, and harmful ingredients in there at worst.

Rather than opting for fat burners, take a moderate calorie deficit if you want to achieve weight loss and be patient – fast weight loss is not better than slow weight loss! If you’re struggling to lose weight on a calorie deficit, it’s most likely that you’re underestimating the amount of food you are eating. Make sure you track everything you eat, from the milk in your tea to the butter on your toast, for a few days to make sure you are in a deficit. You can also increase the calories you burn each day by upping your NEAT, to help create a deficit.

In summary:

Supplements should be the final consideration when your aim is to lose body fat, even more so if the foundations (total calorie intake) aren’t in place. After all, supplements are there to simply “supplement” a diet, and should not be relied upon as a major determinant in your fat loss journey. Fat burners in particular are typically an expensive way to get a caffeine boost, and can have the potential to cause harm.

My advice would be to focus on your total food intake before you even consider the use of supplements. Look at your daily habits. Are they giving you the stable foundation needed in order for fat loss to occur? If the answer is “yes, that’s great” - keep going, consistency is key. If the answer is no, it might be time to reassess your priorities and adjust your habits. You’ll find plenty of tips, advice and recipes over on our Diet and Nutrition section.

Myth 3: Can I Eat As Much Fruit As I Want?

Many people have been told that they can eat as much fruit as they want while trying to lose weight, or that fruit doesn't count when it comes to weight. I’m all for people consuming fruit and veg as part of a balanced and optimal diet, but when it comes to weight loss, there can be such a thing as too much fruit.

Fruits are great for our health, and can be a good tool for anyone on a calorie deficit. A lot of fruit is low calorie but packed with vitamins and minerals, fibre, and water, which makes them a healthy and filling option during the day. However, the calories in fruit can add up, and if you’re eating more calories than you take in, you’re not going to lose weight. You can learn more about fruit with our guide to sugar in fruits here.

If you want to eat plenty of fruit, do so, but remember it’s your overall calorie intake that determines if you’re in a calorie deficit.

In summary:

Getting plenty of fruit each day is a great way to ensure you are packing your diet with vitamins and minerals, but don’t go overboard if you’re trying to lose or manage your weight. It’s also ideal to make sure you get a mixture of fruit and veg each day, not just fruit.

Myth 4: Does Eating Smaller Meals More Frequently Speed Up Your Metabolism?

This is a common myth, and one that I can see the logic behind – the idea that eating smaller meals more frequently as opposed to fewer, larger meals, boosts the amount of calories burnt each day due to the thermic effect of food (TEF), however this isn’t true.

The thermic effect of food accounts for the number of calories you burn digesting food, and it’s the total intake of calories that determine the net thermic effect of food – not how often you eat. For example, if you have two people both eating 3000Kcal per day and person A decides to eat 3 times a day (1000 Kcal each time) while person B decides to eat 6 times per day (500 Kcal each time), at the end of a 24-hour period, both would have the same TEF if they ate the exact same food.

That said, different macronutrients do have different thermic effects – protein uses the most calories to digest (around 20-25%), followed by carbs (5-15%) and then fats (0-5%). So eating more protein can increase the number of calories burnt through digestion.

One benefit of eating regularly, as opposed to fewer and larger meals, is that you don’t go through extreme hunger and fullness cues so are less likely to binge, and it can also help to keep your blood sugar stable. So, eating regularly can be useful, but not because it boosts metabolism.

In summary:

Focusing on what you’re eating rather than when you’re eating is more beneficial to anyone with dietary goals in mind.

Key Takeaways

While there’s plenty of good nutrition advice out there, it’s often nestled among inaccurate or misleading advice which can be unhelpful for anyone who’s looking to improve their diet or lose weight. Even for good advice, it’s rarely a case of one size fits all – some people may fare well on a lower carb diet, whereas others would really struggle.

When taking blanket advice, always remember that we are individuals and there is no one best approach. Optimal nutrition is a very individual lifestyle choice, and while most people will benefit from moving a little more and eating more fruit and veg, what this looks like will vary from person to person depending on multiple factors including age, activity levels, gender, medical conditions, and more.

Hopefully, this blog has highlighted that a healthy lifestyle or weight loss doesn’t need to mean dietary extremes or ‘hacks’, and that most people can enjoy all foods in moderation and still lose weight without having to resort to supplements or forcing themselves to eat (or not eat) certain foods.

When making changes to your diet, ask yourself questions like what food do you enjoy, what changes are sustainable, and what movement will you keep up – these will help to ensure you make lifelong changes for lifelong results.

Our recipes section is filled with healthy, nutritious meal and snack ideas, so check it out for inspiration. If you’re learning about nutrition as part of a healthy living regime, then heading to your nearest PureGym and booking a session with one of our expert Personal Trainers is a great way to start.

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