Weight Loss Myths – Part 1

by DeanMcKillop 11314 views Weight Loss

Weight Loss Myths – Part 1

If you’re sick of hearing outlandish claims about what is good or bad for weight loss, leaving you unsure of what to believe and what to discard, this is the article for you. Written in two parts, I will be delving into the top 8 weight loss myths and why their claim is, in fact, false. Today’s top 4 includes eating frequency, carbohydrate timing, cardio use, and cardio timing. Here we go…

The Claim: You must eat every 3 hours 

The Facts: Your metabolism is determined primarily by your body composition, whether you are male or female, your exercise output, your daily energy expenditure from non-specific exercise and finally the amount of food you eat in total (calories) but not the amount meals you eat (quantity and frequency).

The effect of food on your metabolism is known as the Thermic Effect of Food (TEF) of which it is only responsible for approximately 10% of your calorie burn each day.

The TEF is defined by the total calories consumed over the day, not the frequency of food consumed.
Eg: The TEF of 6x500 calorie meals is the same as 3x1000 calorie meals as both equate to 3000kcal at the end of the day provided their macronutrients (protein/carbs/fats) were also the same.

The Claim: No carbs after dark

The Facts: There is no real history on the creation of this myth other than those that work on the insulin hypothesis, whereby it is claimed that insulin is the primary cause of fat gain and due to carbohydrates effect on insulin they should be removed at night to prevent fat gain.

Unfortunately, it is undeniably incorrect and completely false.

Provided the calories you consume in an entire day do not exceed the calories you burn, whether you eat your carbohydrates at night, morning, all day or lunch time, has little to no bearing on fat loss/gain.

Furthermore the insulin hypothesis has recently been squashed in a study on the effects of a ketogenic diet (high fat/low carb) versus a diet of the same calories but eating carbohydrates, of which there were no positive fat loss effects during ketosis.

The Claim: You need to do cardio to lose weight


The Facts: Cardio is simply just another exercise modality that both burns calories and has health benefits for your cardiorespiratory system (heart and lungs).

Fat loss is determined by the energy balance equation, whereby if you eat fewer calories than you burn you will lose weight/fat, so how you achieve this is up to you.

Arguably, too much cardio may even be detrimental to fat loss due to its negative implications for increasing the risk of muscle loss in severe caloric deficits and should only ever be used as a tool in a fat loss phase as opposed to the primary exercise choice.

The Claim:  Cardio must be fasted to burn fat 

The Facts: While cardio of low intensity in the morning, when fasted, utilises stored fats as its preferred fuel source to perform, this does not offset the energy balance equation listed above.

In fact, even though high-intensity cardio utilises carbohydrates as fuel to perform during exercise, it's after burn effect on using fat as fuel is far greater than fasted cardio.

Regardless of both of these facts, fat loss is still primarily determined by the energy balance equation so enjoy your cardio whenever you like to do it the most. Whether you burn fat during exercise or just throughout your daily activities, is irrelevant as it comes down to the net burn of calories versus the net intake of calories from food. 

Read more in the Fat Loss Myth Series


Exercise Scientist

I completed my Exercise Science Degree at the University of QLD and have worked in the fitness industry for over 8 years, including a short stint at the Brisbane Broncos in 2010 as a student. I also hold my Level 2 Strength and Conditioning Coach accreditation (ASCA) and have competed in 1 bodybuilding season, placing 2nd at the IFBB u85kg Nationals.

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