Metabolic Damage: Alan Aragon interviews Lyle McDonald

eric_sg61 · April 2014

From the article....

"(i.e. if you set up a 30% caloric deficit and metabolic rate drops by 20%, your deficit is only 10% so fat loss is a lot slower than expected or predicted)"

Math is not his strong suit.

Interested to know how he is wrong.

Not saying that I agree that metabolic rate will drop 20% but let's say hypothetically it does. How exactly is the math wrong?

I am terrible at story problems but lets assume the original metabolic rate (maintenance) is 2000cals.

A 30% deficit from 2000cals is 2000cals *0.3 = 600cal deficit. The calories of the diet are 2000-600=1400cals.

If maintenance drops by 20% then 2000*.02=400, therefore the 20% drop in metabolic rate is now a metabolic rate of 1600 cals as opposed to the original 2000cals.

Now the deficit is only 200 calories instead of 600 (1600cals - 1400cals), the deficit is 12.5% instead of 10% (200/1600)*100=12.5. the 10 % comes from the original metabolic rate of 2000 cals (200/2000)*100=10

If my math is off please don't be harsh I am fragile

lindsey1979 · April 2014

From the article....

"(i.e. if you set up a 30% caloric deficit and metabolic rate drops by 20%, your deficit is only 10% so fat loss is a lot slower than expected or predicted)"

Math is not his strong suit.

Interested to know how he is wrong.

Not saying that I agree that metabolic rate will drop 20% but let's say hypothetically it does. How exactly is the math wrong?

I am terrible at story problems but lets assume the original metabolic rate (maintenance) is 2000cals.

A 30% deficit from 2000cals is 2000cals *0.3 = 600cal deficit. The calories of the diet are 2000-600=1400cals.

If maintenance drops by 20% then 2000*.02=400, therefore the 20% drop in metabolic rate is now a metabolic rate of 1600 cals as opposed to the original 2000cals.

Now the deficit is only 200 calories instead of 600 (1600cals - 1400cals), the deficit is 12.5% instead of 10% (200/1600)*100=12.5. the 10 % comes from the original metabolic rate of 2000 cals (200/2000)*100=10

If my math is off please don't be harsh I am fragile

I came up with 12.5% too.

bethlaf · April 2014

awesome,

heybales · April 2014

Interesting to see that at least 1 study showed the same effect in overweight pretty much non-exercising people.

Doesn't just have to be the athletic person taking huge deficit, could be non-active taking 25% reduction off TDEE in this case.

http://www.myfitnesspal.com/blog/heybales/view/reduced-metabolism-tdee-beyond-expected-from-weight-loss-616251

And no, I didn't just re-write that after reading this article, already written that way.

Edit - usually I see both of them talk about ease of compliance more.
And what is likely easier to comply to, totally suppressed and you kept cutting calories to cause the desired weight loss, or slower and less suppression, giving higher eating level?

SezxyStef · April 2014

I as a not so bat *kitten* women dieter have too many in my life...and I will be sharing this article that is full of great information and the language made it a fun read.

I have already shared it with friends mostly women in hopes that they too can share it.

Again Thanks OP for the post...

mycupyourcake · April 2014

So when someone complains about not losing at X number of calories there's several possibilities.

1. They aren't really eating X calories. They are logging incorrectly, either not weighing, forgetting binges, or not logging on the weekends, etc.

2. They are losing weight but due to messed up stress hormones they could be retaining an incredibly large amount of water, masking their weight loss.

3. They aren't really eating at a deficit because the weight they've already lost has resulted in a lower TDEE.

4. They aren't really eating at a deficit because their activity level has dropped considerably due to the fatigue caused by eating less calories and/or stress hormones.

5. Or some kind of combination of points 1-4.

You forgot to add the point about if they are a bat crazy female dieter they need a good **** in order to chill the **** out and lower the cortisol levels in order to get rid of all that water weight. My husband will love this part of the diet.:blushing:

:smokin:

tigersword · April 2014

"And fundamentally, dieting is just controlled starving to death."

Might be my new favorite quote. :laugh:

ktcomplicated · April 2014

Read the whole thing. Good read and in support of what I've come to understand from the forums and my own reading. Nice to have it summarized all in one link though very cool.

My thoughts exactly.