Fat Makes You Fat/Fatter

Acg67 · February 2013

You've prob heard quite a few people, here and elsewhere, say "Fat doesn't make you fat". While true it is excess calories that makes one fat, not any particular macronutrient, does eating a surplus of fat make you fatter than other macros? The answer to that would be yes.

Ketogenic diet-fed rats have increased fat mass and phosphoenolpyruvate carboxykinase activity

http://onlinelibrary.wiley.com/doi/10.1002/mnfr.200700415/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+on+23+February+from+10:00-12:00+BST+(05:00-07:00+EDT)+for+essential+maintenance

KD-fed rats gained weight at a less rapid rate than normal-fed rats, but with a significant increment in fat mass. The fat mass/body weight ratio already differed between ketogenic and control rats after the first week of treatment, and was 2.4 x higher in ketogenic rats

Before you scoff at it being a rat study, keep in mind that the esteemed Gary Taubes used rats as evidence carbs were evil in his books and the fact that DNL is much more efficient in rats than humans.

Fat and carbohydrate overfeeding in humans: different effects on energy storage. American Journal of Clinical Nutrition, 1995; 62: 19-29.

www.ajcn.org/content/62/1/19.full.pdf

Carbohydrate overfeeding produced progressive increases in carbohydrate oxidation and total energy expenditure
resulting in 75-85% of excess energy being stored. Alternatively, fat overfeeding had minimal effects on fat oxidation and total
energy expenditure, leading to storage of 90-95% of excess energy. Excess dietary fat leads to greater fat accumulation than does excess dietary carbohydrate, and the difference was greatest early in the overfeeding period.

So while fat may not make you fat in an of itself it does appear to make you fatter than the other macros. Just a friendly FYI

Mokey41 · February 2013

The key being excess. Eating a sensible amount of fat in your diet will not make you fat. The statement that fat doesn't make you fat is usually being given to 1200 calorie dieters who are avoiding eating any fat at all.

Krys_140 · February 2013

Huh. Interesting!

Jonesie1984 · February 2013

interesting and @Mokey41 I would say excess anything in macros is going to have a negative effect on the person.

d2footballJRC · February 2013

I wonder if this correlates with proteins and carbs are usually 4kcals per grams and lipids (fats) are 9kcals per gram on energy. That could explain a bit on the extra storage.

If 1 gram of protein/carbs is equal to 4kcals, and 1 gram of fat is 9kcals per gram and you are eating excess wouldn't it make more sense that fat would lead to a larger amount of storage?

joejccva71 · February 2013

So Acg during a bulk, would you recommend keeping fats at .35g per lb of bw and shoving the rest of the cals in carbs? Or even lower than .35 depending on how lowering fat may affect you in other ways (brain functionality, sanity, libido, etc).

MaraDiaz · February 2013

Well that is interesting. But my body can't store it if I'm in a calorie deficit and the more fat I eat the easier it is to stay in that deficit because fat keeps me from being famished.

This could be a concern when I start working on maintenance though.

ngyoung · February 2013

I can't access the full study. What type of fat were they feeding the rats. If it is the one I am thinking of they were using an unnatural food source. This could get into a pretty long thread filled with all kinds of study links debating either side of the argument though.

DaughterOfTheMostHighKing · February 2013

Your body needs fats. good fats from nuts and fish. Your brain cells are fat cells. so not fat, brain starves... no brain. lol!!! not really, but funny to think about all those people avoiding all types of fat!

shedoos · February 2013

So Acg during a bulk, would you recommend keeping fats at .35g per lb of bw and shoving the rest of the cals in carbs? Or even lower than .35 depending on how lowering fat may affect you in other ways (brain functionality, sanity, libido, etc).

I'm interested in Acg's answer to this...

Acg67 · February 2013

I can't access the full study. What type of fat were they feeding the rats. If it is the one I am thinking of they were using an unnatural food source. This could get into a pretty long thread filled with all kinds of study links debating either side of the argument though.

Lard

Acg67 · February 2013

I wonder if this correlates with proteins and carbs are usually 4kcals per grams and lipids (fats) are 9kcals per gram on energy. That could explain a bit on the extra storage.

If 1 gram of protein/carbs is equal to 4kcals, and 1 gram of fat is 9kcals per gram and you are eating excess wouldn't it make more sense that fat would lead to a larger amount of storage?

The human trial had the same surplus between cho overfeeding and fat overfeeding groups

llkilgore · February 2013

You don't go into ketosis because of high fat. So what happens with a high fat, moderately low carb, non-ketogenic diet?

Sarauk2sf · February 2013

Seems legit!

sz8soon · February 2013

interesting..what is going to be more interesting is what the actual take away people will get from this post.

Cr01502 · February 2013

Interesting.

Thanks for posting.

EvgeniZyntx · February 2013

Full study available here: http://onlinelibrary.wiley.com/doi/10.1002/mnfr.200700415/pdf

BurtHuttz · February 2013

I am not a rat*.

*This is completely and totally irrelevant to the original post, but I see that people on this website like to respond to research by saying that they are not the species studied, and I wanted to try it out for myself. It feels as dumb when I write it as I think they are when I read it.

geebusuk · February 2013

Wouldn't a ketogenic diet is significantly different to what your typical 'normal' high fat diet would be like?

The state of 'Ketosis' which then follows I thought meant that the body did work differently.

EvgeniZyntx · February 2013

I am not a rat*.

*This is completely and totally irrelevant to the original post, but I see that people on this website like to respond to research by saying that they are not the species studied, and I wanted to try it out for myself. It feels as dumb when I write it as I think they are when I read it.

Maybe.

Here is my read of the study.

The keto diet rats experienced less weight gain and higher fat / body mass ratios. Some of the criticisms that are reasonable to make, and that the authors also mention:

- this is a "eat all you want" study - possible during restriction (I am not a rat eating like a little pig) the results will be quite different.
- the fat accumulation seen with these rats has not been reported with equivalent diet in children using these diets as therapy for convulsions (am I more a child than a rat?)
- insulin resistance increase seen in this study for the keto diet rats is actually the opposite of the insulin sensitivity seen in humans with keto diets (rats are different about some biological markers)

Despite these comments, it is a very interesting study, and I'd say that the methodology and the authors conclusions suggests that one of the followup should be a cross-over (my thought) with calorie equivalent restriction - no one here really eats as much as possible.

What it does suggest is:

- macros are very, very important.
- maybe, just possibly, and to be verified, bulking with a keto diet (high fat/high protein) is a bad idea in terms of body composition
- mechanism of weight control in keto diets are more related to satiation (my conjecture), since the rats ate less in ad libitum.

Thanks for the article!

neanderthin · February 2013

Yup, dietary fat might not be the go to macro for building lean mass.

ILiftHeavyAcrylics · February 2013

This is really interesting, thanks for posting! :drinker:

(Especially interesting for me because I am *always* over on fat, which isn't a problem right now because I'm not eating a surplus, but it's good to know for the future)

kennie2 · February 2013

its kinda the same way that carbs make you fat
and protein makes you fat
and fruit make you fat
and anything in excess will make you fat

ILiftHeavyAcrylics · February 2013

its kinda the same way that carbs make you fat
and protein makes you fat
and fruit make you fat
and anything in excess will make you fat

Right, but

Excess dietary fat leads to greater fat accumulation than does excess dietary carbohydrate,

So yes, a surplus will cause weight gain regardless, but fat results in gaining more fat than carbs.

tobilinjo · February 2013

and the difference was greatest early in the overfeeding period.

Yeah, what would happen, if they had the ability to better adapt to this "new" macro?

How long had this study been going?

neanderthin · February 2013

its kinda the same way that carbs make you fat
and protein makes you fat
and fruit make you fat
and anything in excess will make you fat

Right, but

Excess dietary fat leads to greater fat accumulation than does excess dietary carbohydrate,

So yes, a surplus will cause weight gain regardless, but fat results in gaining more fat than carbs.

Carbs are protein sparing resulting in a better ratio of lean mass to fat accumulation.

EvgeniZyntx · February 2013

and the difference was greatest early in the overfeeding period.

Yeah, what would happen, if they had the ability to better adapt to this "new" macro?

How long had this study been going?

Then they would adapt better. What is your question?

6 weeks.

Faye_Anderson · February 2013

interesting and @Mokey41 I would say excess anything in macros is going to have a negative effect on the person.

I don't necessarily agree, people have their macros set in varying ways and get the same/similar results so I think there is room for a little extra without negative effects. People who have "excess" protein seem to thrive here :flowerforyou:

tobilinjo · February 2013

and the difference was greatest early in the overfeeding period.

Yeah, what would happen, if they had the ability to better adapt to this "new" macro?

How long had this study been going?

Then they would adapt better. What is your question?

6 weeks.

I guess, longer study time would show different results.

Especially when they would use different fat sources. lard sucks :-)

EvgeniZyntx · February 2013

and the difference was greatest early in the overfeeding period.

Yeah, what would happen, if they had the ability to better adapt to this "new" macro?

How long had this study been going?

Then they would adapt better. What is your question?

6 weeks.

I guess, longer study time would show different results.

Especially when they would use different fat sources. lard sucks :-)

Why? What do you base your conjecture on? Look at the graph. At 6 weeks you have a differentiated starting point - a leaner rat but higher BF% on the keto - what makes you think things are going to go differently from that point?

Not challenging, I'm interested in your development of the idea.

BeachGingerOnTheRocks · February 2013

Thanks for the data. Honestly, it's really useful for me right now, so big extra thank yous!

Obviously, I'm not in sync with the test subject because even though I am "bulking", I do not eat a significant amount over maintenance. If there is an impact in gaining less fat while adding mass then right now is exactly the time for me to test it on myself. I have been reading a lot on nutrition and thinking that my fats were more important than carbs. I've been eating around 50+ grams of fat most days, which is .4 or my total body mass (yes, I'm small). Probably should cut it back a few grams and see if I get better results. I will note that my bf% has gone down since I started eating this way, but it coincided with a change to the 5/3/1 lifting program and upping overall calories, particularly protein, so we will see.

Fat Makes You Fat/Fatter

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