July 27, 2016

The 6 Surprising Reasons “Fat Burning Foods” Aren’t All that Super for Weight Loss

‘Superfood’ is one of the most used catchwords in the health and fitness industry today, and sits alongside other concepts such as ‘fat burning foods’.


Some say these words are just carefully constructed marketing terms designed to sell products, while others swear certain foods have magical health benefits that everyone, including YOU, should get in on immediately.


What is a superfood?


Well it’s a food that
supposedly increases a person’s metabolism in a significant and unique enough way that you can lose fat just by eating it (or at least lose more fat than you would by eating a comparable non fat burning food).


So, I guess the burning question is: are there actually foods you can eat that will help you increase the amount of body fat you can burn?


The answer is, well, sort of, and sort of not. Read on. 

  1. Food digestion does burn calories.


Every food you put into your body requires the use of energy in order to digest it.


This is called diet induced thermogenesis (digesting food)
and it’s one of only three methods the body uses to expend energy, which is pretty cool scientifically speaking.


The other processes which burn calories are: Basal Metabolic Rate (the amount of energy your body uses just to serve basic functions like breathing), and exercise (the non-essential activity you choose to partake in by general daily movement and working out).


Now, while thermogenesis may sound like a pretty big deal, if you really stop to think about it, what it means is that by definition ALL foods are fat burning foods, as ALL foods lead to some amount of increased metabolism.

  1.  Digestion burns less calories than other methods, by far.


So, before you get too excited about this whole thermogenesis thing, the first thing you need to know is that only around 10% of the calories you consume are burned during food digestion.


Really, the effect is so minute that I’m not sure thermogenesis and the idea of ‘fat burning foods’ should even be on anyone’s radar…


Simply ‘existing’ is going to burn ten times as many calories as digesting any food ever will, and an hour of moderate exercise each day will burn almost twice the calories your body will burn by digesting every single piece food you eat in a day.

  1.  Yeah, but do some foods require more energy to digest than others?


Protein takes the most energy to digest (20-30% of total calories), and then carbohydrates (5-10%), and then fats (0-3%).
 


So in that sense, yes, eating a diet high in protein is going to require more energy usage to digest meals than a diet high in carbohydrates.


But again, these differences are very insignificant when it comes to overall daily caloric expenditure,
and, saying that protein takes more energy to digest than a carb is a far cry from claiming that specific foods as having unique fat burning properties. That my friends is just going way too far.


This leads me to my next point.

  1.  All food contributes to weight gain in certain quantities.


Even if you only eat foods that use the most calories to digest, this method of dieting is totally negated as soon as you consume more energy than your body expends.


So, while a large portion of the population is buying into the idea of eating certain foods to lose weight, the reality is that they should probably just focus on eating less food.


But what about all the ‘
a calorie isn’t a calorie’ studies out there?

  1.  A calorie probably IS just a calorie.


I know, I know, many popular health and fitness sites have suggested that if you eat certain foods you will lose more weight than if you eat an equal quantity of other foods.


Here’s the thing. They’re basing their statements off of just
one basic study…


The study compared a whole foods diet of sandwiches to an equally calorie dense processed food diet of sandwiches, and found that the whole foods group had a higher post meal thermogenesis rate than the processed food group. At the end of the day, there was not a highly significant difference that would likely contribute to long term weight loss, but a difference none the less.
 


But, take a look at this:

Notice anything?


Remember when we mentioned earlier that protein requires more energy to digest than carbs?


Take a look at the protein and carb ratios of both the whole foods and the processed food groups, and tell me what you see…


That’s right, the processed food group has a significantly lower protein density than the whole foods group.


So, the
only study currently referenced to compare equal calorie dense foods with a different thermogenic outcome, didn’t even use foods with the same nutrient profile. Knowing that certain nutrients use more energy to digest than others, do you think this should be looked at as an adequate study to base wide sweeping conclusions on? I don’t.


Don’t get me wrong, I’m not saying that it isn’t better to avoid processed foods. There are many health reasons to eat a diet of whole foods over processed foods, but increasing the ‘fat burning’ effects is not likely one of them.

  1. Genetic factors matter.


What
does appear to play a significant factor in individual thermogenesis is a person’s genetics and current state of health.


Studies have shown that people who are obese have a lower thermogenic effect than those who are not obese.


This would suggest that the current composition of your body may have a significant effect on all foods you put into your body, making the state of your health a much larger contributing factor to thermogenesis than the foods you are eating.


So, where does this leave us?


Do ‘fat burning’ superfoods exist?


It doesn’t appear so…


Although protein has a higher thermogenesis rate than carbohydrates, and carbohydrates have a higher thermogenesis rate than fats, the effects are small and don’t really impact real life weight loss.


The bottom line is that we are always looking for something to come and save us rather than do the things we know we need to do to lose weight and be healthy
the hype of ‘fat burning foods’ is a great example of this mentality.


If you want to make ALL foods ‘fat burning foods,’ I think you should just exercise regularly and take care of yourself!
 


After all the current state of your health and genetic factors
do play a significant role in how many calories your body is able to burn. So, focus less on picking magical foods and more on just staying active and being food conscious, and you’ll be just fine.


What’s your take? Tell me what you think.


References

Barr, S.B. and Wright, J.C. (2010). Postprandial energy expenditure in whole-food and processed-food meals: implications for daily energy expenditure. Food Nutrition Research, 54(10).  Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2897733/.

Westerterp, K.R. (2004), Diet induced thermogenesis. Nutrition & Metabolism,1(5). Retrieved from http://nutritionandmetabolism.biomedcentral.com/articles/10.1186/1743-7075-1-5.