Thank you everyone for all of your votes, the results have been very interesting to say the least.
What was supposed to be a very simple experiment has actually opened my eyes to some very interesting findings. I’ve learned that most of us (myself included) think of ‘metabolism‘ using a number of assumptions, which may, or may not, be correct.
The first assumption is that a faster metabolism is a better metabolism. Interestingly, outside of fitness dogma there is no real evidence to suggest that a higher metabolism is a healthier metabolism. In fact, there is research to suggest (but not prove) that there is a correlation between an elevated Basal Metabolic Rate and mortality. However, I doubt there’s any relation at this level, which leads to point two…
As some of you rightfully pointed out, we have very little concept of the magnitude of difference required to truly consider a metabolic rate, high or low. The two examples I gave had *roughly* a 200 calorie difference over 24 hours. Some people made the assumption that a 200 calorie difference is ‘next to nothing’ while other made the assumption that this number was large and significant.
You’ll notice that I said (or typed) *roughly* in the paragraph above. I did this because our standard 4 calories per gram of Carbohydrate, 4 calories per gram of protein and 9 Calories per gram of fat are actually just estimates. Not only this but they are estimates for the calorie content of the Carbs, Fats and proteins in our foods, not our bodies (so they take into account digestion ‘losses’). And within our bodies there is actually a fair amount of variation of how many calories (energy) a gram of each can provide, especially in the protein – depending on the amino acid make up this number can very greatly.
The other assumption we tended to make was that a higher oxidation rate of protein was ‘bad’. True, on the surface it seems to scream ‘muscle loss’, but in reality it COULD be a higher rate of protein turnover that includes a better rate of breaking down damaged proteins in the body and replacing them with new ‘undamaged’ proteins….in this light a higher protein turnover could be a good thing…quicker recover and even better, more durable muscle building…Healthier organs..we just don’t know..after all – It could also mean muscle loss or even a disease state.
I’ll admit that when I posted the question I really didn’t have a preconceived answer to which one was ‘best’. One obviously burned slightly more calories, while the other slightly more fat.
As was rightfully pointed out the differences were small enough to probably be inconsequential.
In fact, both are realistic fluctuations in metabolic rate that you would go through depending on time of day, what you ate, fasted versus not fasted etc.
One of the important lessons from all of this is that regardless of which metabolic rate you ‘had’ in the scenario, the answer to ‘how would I lose weight?’ would be the same – eat less.
In general – The point I was hoping to make is that we spend far too much time worrying about our metabolism.
Yes, if the difference was 200 calories, and you calculated that out over a year it would be a 70,000 calorie difference, and while 70,000 sounds really impressive the question is – does it really matter? The same question can be asked about the 0.3 grams difference in fat oxidation. Yes, if calculated over a year and assumed to be ALL body fat it equates to around 6 pounds of Fat…but does this matter?
In fact, it seems from all of this that what really matters is the calories we put IN to our bodies.
Yes, metabolic rate stuff is sexy, and most arm-chair physiologists think they have it all figured out…even though most of what we know are generalized estimates based on populations, but the truth is…metabolic rate is a big vague grey area. All those metabolic equations that we use to predict our metabolic rates are actually mediocre at best in there estimates. They are useful for predicting the average metabolic rate of a group of people with similar characteristics, but not the metabolic rate of an individual. Simply put, You do NOT know how many calories you burn – neither do I.
Even if you spent 24 hours in a respiratory chamber, or did a test with doubly labeled water..it only tells you the amount of calories you burned during the test. The test might last 2 hours or several days – it doesn’t really matter.
Yes, we have some great ball part numbers – but that’s all they are…ball park
So suggesting that we can measure a 0.3 gram difference in fat oxidation, and that this difference would survive over hours to days is a mistake (one that I suggested in my last blog post – so my fault, not yours), so is assuming that a 10% decrease or increase in your metabolic rate is a good or bad thing.
We really don’t know.
Which is why the answer to our weight loss issues becomes “eat less”, and “eat the amount that allows you to lose weight”… not the amount the online calculator says you should eat, not the amount your friend ate to lose weight, not the amount that ‘sounds right’.
The biggest mistake we have been making is ‘setting’ an amount of calories we THINK we should be eating for weight loss. Then when that amount doesn’t work, instead of accepting that our assumed number could be wrong, we immediately move to thinking that WE are somehow broken, damaged or wrong.
Chances are there’s nothing wrong with your metabolism, just the assumptions and estimates that people constantly push on you.