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C+F Meals Why Not?


Hey guys, any of you fans of JB out there high five :slight_smile:

Anyways, I'm just trying to understand better exactly why should we try to avoid mixing Carb with Fats in one meal? Sorry if I'm asking a dumb question! My understand on this is, it has something to do with insulin levels increasing?

If someone could it explain this to me in a very simple way without using to many fancy terms, that would be great.

Also Insulin, is responsible for delivering the goods to the construction site so to speak....Please help me understand this better.

Again I don't feel very bright asking this, but I just find it a little to confusing with my english reading all those studies on this stuff, they use too many techincal terms and I just get lost.

Thank you


This is my understanding.

When you consume carbs, your insulin level increase as a result. When your insulin levels are high, your body stores dietary fat as body fat instead of using it for energy.

What is insulin? Insulin is the hormone in your body that transports nutrients into the cells. The bulldozer analogy works like this...

Carbs = Bricks
Your bodies cells = Construction site
Insulin = Bulldozer

The reason Diabetics take insulin is because if you don't, your cells simply don't get nutrition...bad news. Hope that helps.


to oversimplify: carbs will 'open up' your cells so add protein and protein goes into your muscle cells (good). add fat and fat goes into your fat cells... (bad).

eat fat without carbs and it'll sit in the blood and be used as energy (also it will make your body think you are not needing to store more fat since you already have plenty floating around, so it can release some to burn)

way oversimplifies, but thats the jist.


Insulin is a hormone secreted by the pancreas that regulates blood sugar. Carbohydrates are essentially sugars, and as such, consuming them increases your blood sugar levels, and consequently the pancreas releases insulin to regulate this change. GI, the glycemic index, is an index of glucose absorbtion into the blood by eating that particular carbohydrate (donuts and such having huge GI, chick peas and oatmeal having low GI). The correlation between GI and insulin release is not always well-balanced (ie, high GI does not always mean high insulin release) but for the sake of simplicity, you can say this is true.

Beyond this, I can't explain everything very well, but suffice to say, what people have already said is the right idea. Insulin does a number of things, among which there is increased amino acid uptake (forced absorbtion of circulating amino acids--protein--into muscle cells, which is why P + C meals are great). If it helps at all, think of P + F meals to do the same thing, except this time, fat is circulating, not protein.


Fat will only be stored if there is fat present. Malonyl -CoA exists in high amounts when there is plenty of metabolic fuel present. Thus, carnitine acyltransferase is inhibited and
this in turn prevents acyl-CoA from crossing into the cell?s mitochondria. Another enzyme is inhibited by the presence of NADH and Thiolase is also inhibited by the presence of Acetyl-COA. In short, when a lot of glucose is present, fatty acid metabolism is inhibited.

It is the last sentence that clues us in here. Basically, a cell will not convert fats into energy if there is glucose present. When the cell has carbs and sugar to work on, it will not convert the fat to energy, thus the fat gets stored.

This is why the low carb diets work, with little to zero carbohydrates and
subsequently glucose to work on, the fat will be used for energy. This is exactly why the high carb diet works too. When no or little fat is present, it won't be stored as fat.

In addition to this, it is important to realize that it costs the body quite a bit of energy to take carbs and store them as fat. This alone is actually a positive. There really needs to be some form of fat present to make it easier.


I dont get all boiled down in what to mix with what. I would stick to eating clean, that in itself is hard enough. I know plenty of lean people who mix carbs and fat.


Berardi's p+c and p+f system is a good way to gain lbm, but its not the only way. I find it easier to just eat a healthy balanced diet with 300-500 cals above maintenance to gain 1 or more lbs a week. Anything beyond 2lbs a week (unless you are on gear) is bound to have a higher fat percentage attached to it.


please do a search on this topic. this website may be the one that has the least amount of information that explains why the C+F thing is wrong, but it's here.

FYI, John Berardi doesn't even espouse his original C+F ideas anymore, yet a large amount of followers do.

ever drink milk? did our ancestors? massive C+F combining going on there and exactly zero evidence suggesting that when cals are matched lower carb milk stimulates less fat gain. why no evidence? because it doesn't.

ever eat often? like six times a day? did you know that digestion takes a much longer time than most would have you believe? guess what that means? it means that your P+F meal is still in your stomach when you put a P+C meal in your stomach. why does this not effect F+C combinations?


I think this topic is becoming taboo, similar to the way GI used to be all the rave and has petered out to a much smaller significance. The idea is to look at things in perspective and also not to anything in extremes.

For example with the GI business, it was only very important if you were considering very high GI food taken after many hours of fasting, in large amounts, on their own. For example: waking up after 8 hours fasting and eating 100g dextrose powder alone. But in the real world, these situations do not occur so GI is not too important (not saying insignificant, but far less important than once thought).

Ditto on the nutrient combining: only at times like PWO when you are getting a large dose of sugars, do you want minimal fats. This is when insuling IS heavily elevated so the presence of fat is not ideal. That is one reason why many people go the low GI / oats root PWO (that's another debate altogether though :slightly_smiling:


so are you saying that the P+f/P+c method is no longer being advised by Berardi and Lowery?


Minimal carbs PWO?


Edited. Was supposed to be "minimal fats". You know what I meant :stuck_out_tongue:


another fad diet???? It cant be!!!!

history repeats itself.


Perhaps the more important idea is that regardless of what they advise, nutrition and success in physical goals is not as simple as following the every word of any particular trainer. Some of the leanest people I have known who maintained that condition over the long term cared the least about how they grouped their meals together. It is simply another concept that you can throw in your bag and either use or NOT use. I would hope the goal is to avoid simply being a cult worshipper and actually learn to think for yourself.


P+F/P+C has been modified to the point that it's okay to eat moderate amounts of carbs with moderate amounts of fat. im wondering what JB thinks BBers and health conscious athletes have been doing all along.

there is just no evidence that proves it works, and loads of evidence that proves it doesn't. what any 'guru' thinks on top of what is known proof is irrelevant.

although, advising P+C/P+F is much different than stating that metabolism is different. many people will see good fat loss when adhering P+C/P+F, but not for the orignally purported reasons. espousing P+F/P+C is a very good way to reduce calories without trying. all evidence has shown that the only way to lose weight via diet is by reducing total caloric intake (excluding what can be minute and/or unusual details). P+C/P+F effects fat loss only when it is a reduction in calories (or positively alters nutritional status, like, changing from low protein to high protein).


I'm not too anal about it though.I wouldn't say not to all carbs with all fats.However,I would say not to mix high GI carbs with a lot of saturated fats.Mixing some low GI carbs with fats is fine.


Amen!I second that.


yes it is.

the need for carbs PWO is quite overrated for at least three reasons:

  1. if carbs are already in your belly from a meal before WO it wont matter about PWO because digestion is already happening and nutrition is in your bloodstream (where it matters).

  2. protein synthesis is a forever process, and IIRC it peaks at 24 hours PWO. this 2 or 4 hour window stuff is wrong. although, converting from catabolism to anabolism PWO is necessary, it's not nearly as big a deal as purported (i dont know the exact reasons though).

  3. carbs that are necessary to replenish depletion from WO is often far less than what is popularly believed. 40g of carbs is a lot.

i bet that the two biggest reasons that people see results when adhering to PWO are:

  1. more cals, more psychological bulking diet adherence.

  2. WO is on an empty stomach. i still dont think this one is a huge deal because i believe that what matters is total daily intake.


Good posts by wufwugy.

JB's previous recommendations of not combining Carbs and Fats are mostly from his personal experience. Currently he seemed to have revised his recommendations to protein+fat+smart carbs meals, which is a lot more similiar to what bodybuilders have been doing all along.

Get sufficient total calorie, protein and EFA intake. There is no scientific evidence that not mixing carbs and fat makes any difference (read the John Berardi quote above).