Protein, fat, calories. Clarification needed


Hi there,

Need some clarification. So, I understand that on a keto diet you are restricting your carb intake, but I am slightly confused on the other two macros, i.e protein and fat. Maybe this is paralysis by analysis.

I see people fast, yes they are trying to control their insulin but they are as well restricting caloric intake, so how much should you reduce caloric intake, what’s too much or too little.

Protein. Protein turns to carbs if you over do it, so do we limit protein? But if so, how do we add fats?

Lastly, fats. Yes fats satiate but can excess dietary fat cause you to gain weight?

It seems in progression of keto talk and advise, people say eat this, not that, but not too much and not too little, and don’t forget not to eat.

It’s confusion. Can someone simplify. I want this to work, but I feel no one has a concise plan.

(Michael - Don't expect miracles and you won't be disappointed.) #2

The only thing you arbitrarily restrict are carbs: sub-20 grams per day. Unless you have some specific metabolic and/or health issues, fat and protein are pretty much ad libitum. Generally you will eat more fat than protein. Even if you eat equal portions of fat and protein by weight, because fat is 9 calories per gram and protein 4 calories per gram, so you will still get more than twice as much energy from fat as protein.

Protein does not turn into carbs. Gluconeogenesis is demand driven, not supply driven, and fat as well as amino acids from protein can be used as the basic ingredient. Generally, more protein than necessary for maintenance/repair will turn into expensive calories, not carbs. The idea that protein gets converted to carbs simply because you eat more than you need is very outdated. See Amy Berger’s article below.

It may sound counter-intuitive, but eating fat burns fat. This is because fat increases your metabolism. If you are trying to lose weight/fat then, yes, you will eat less fat than if you are maintaining to insure that your metabolism utilizes your own body fat. But it’s usually not a big difference, maybe a couple hundred calories. This because your metabolism works differently when the main fuel is fat not carbs.

Regarding total caloric intake. The most important thing is not to restrict your overall intake to the point of being hungry all the time. That’s what CICO diets do and why they fail. It’s OK to be hungry before meals, but it’s not OK to be hungry within an hour or two after meals. If you get hungry after meals, you need to eat more at meals.

I’m not much into fasting, but I think the overall intention is not to restrict total calories, but to restrict the timing of eating them.

(Brian Smith) #4

G’day - I’m far from an expert, but perhaps my experience can help you. I agree it all seems a bit uncertain, but i think I got a grip on the key bits:

  1. restrict carbs to 20g per day or less (this is the most important aspect);

  2. try to eat enough calories to fuel your body, so the rest is made up of fat and protein. Ideally more fat than protein.

For me, I use Fatsecret to track what I eat. I was eating only around 900 cals per day prior to taking on keto. I entered my details on a keto website that told me I should be eating a lot more. I have since increased my calorie intake, but i still find it hard to eat more than about 1500 calories per day, so that’s what I do.

I have landed on a sort of diet that gives me lots of fat (eggs, bacon, avocado for breakfast, pork belly and green salads for lunch, with cheese; meat and salad for dinner if I need it (I sometimes skip dinner if I’ve had 1,500 calories by the end of lunch). Lots of water, a bit of black coffee. No snacks.). I enter each meal into Fatsecret and it tells me my carb count in grams.

I don’t count protein and fat beyond a quick glance. I look at the pie chart in Fatsecret to see if I can get 60-70% or more proportion of fat and that’s it.

From the first, I wasn’t hungry or craving for sugar or carbs. I’ve had my fat up to 82% of my day’s calories on one day (with 15.6g of carbs) and have steadily lost weight (I weigh myself weekly) and feel fantastic.

I found, to keep in the 20g range for carbs, I had to drop my morning flat white coffee and I only have fried mushrooms every now and then but its a process of monitoring my carb intake - the rest I pretty much leave alone, beyond trying to eat fatty foods.

I’d say aim to limit carbs to 20g per day or less and not worry too much about protein and fat - just make fat your friend.

Hope this helps.


Greatly appreciate the input. I think I have to focus on just one thing, keeping carbs low, and let the rest work itself out


So, I do alternate day 24 hrs fast and feet as described by Dr. Fung in his obesity code book. On my fast day I get around 900 calories and on feast day around 1500. We’ll see how this works


There are good videos on YouTube by Jason fung but fasting is completely different from calorie restriction in that for fasting you get blood insulin levels low which is the switch/signal for the body to begin accessing fat stores.
If you eat a little throughout the day your insulin will never be low.

(Susan) #8


If you are eating 900 calories a day on a “Fasting” day, that is not fasting.

Fasting is when you only drink water, or black tea, black coffee, with nothing added.

(Wendy) #9

This is a little long but you may find some answers to your questions. Keto can be simple. I like how they talk about how not to make it complex.

(Susan) #11

Fasting is really great, but generally when people are just starting Keto you can do 3 meals a day, then 2, and keep increasing your IF times, and after a while, then start fasting.

(Jack Bennett) #12

The simplest way I have seen it described is this:

Protein is a target - aim for 1.0 - 1.5 g/kg of lean body mass (or 0.5-0.75 g/lb of lean body mass).

Carb is a limit - set your carb ceiling in grams and don’t go above it, based on your own needs and experience.

Eat fat to satiety. Whatever other food energy you need must come from fat, because we just set what protein and carbs will be.

Suppose you’re an 80 kg man with 65 kg lean mass (using my own numbers here). So you need about 100 g of protein which is only 400 kcal. Carb provides 100 kcal at 25 g intake. This adds up to only 500 kcal.

Therefore, all the rest of your food energy must come from fat. If you eat 2000 kcal in a day, 1500 kcal is from fat (167g). If you eat 2500 kcal in a day, 2000 kcal is from fat (222 g). And so on.

This is oversimplified because it assumes steady state, but that’s the main idea: protein is a target in grams, carbs are a limit in grams, eat fat to satiety.

Another complication is the protein debate. The lowest numbers I’ve seen recommended are like 0.5g/kg of lean mass, while programs like LeanGains recommend numbers that lead to like 5g/kg of lean mass. I find it hard to overeat protein - you really have to try hard, use supplements, etc.


To clarify. That 900 calories was the caloric count of the meal after a 24hr fast

(Susan) #14

Oh, okay =). I was confused because of the wording.

Generally when people are starting Keto we suggest the 3 meals a day on an IF schedule to them so that they can adjust first and not feel hungry. Fasting is awesome. I do it 3 days a week atm myself in 44 hour intervals (mon, Wed. and Fri) but I have been on Keto since February and am fat adapted and I don’t get hunger in between. I just don’t want you to get frustrated early on is all.


Some people easily eat high protein. I actually can’t seem to be able to eat only 1.5g/kg, that’s so little even with my not high energy need and generous carb limit! I don’t know how people keep that so low when they need little like me, well I do, we are different, I just need my protein to get satiated and after that fat has a chance too. At least I know I shouldn’t worry about high protein, I don’t eat so very much, after all, 3g/kg is rare, 2g/kg does the trick! I don’t like to eat unnecessarily much but what can I do? (I can exercise more so I could use most of that 2g/kg, maybe. Or try other protein sources, other fats. I plan to do both.)

I saw 0.7-0.8g/kg as minimum but in some circumstances, more is needed and definitely advisable. I am a firm believer of 1-2g/kg, more for more active people and of course, a bit more is needed for bulking and it’s safer to keep it higher at fat-loss though it might be not the case on keto. There are personal differences, some people say they totally can gain muscles at 1g/kg but 1-2g/kg seems a pretty popular range, for a good reason. Bodybuilders, even natural ones often are into higher numbers but even they can’t use as much protein without steroids and that is a different story. Actually, 2 is a tad unnecessarily high but it’s safe enough.
Plant protein can complicate things a bit but I don’t go into it especially not on a keto forum where there are lots of carnivores but no vegans.


Great advise. Thank you

(Jack Bennett) #17

I seem to do OK around 1.5-2.0 g per kg of lean body mass (roughly 100-130g protein at my size).

If I go higher, maybe to 180-200g protein, I definitely notice some ammonia taste/smell, which suggests that I’ve overdone it a little bit. That would be 3g/kg LBM. The LeanGains numbers would be really high for me, but maybe that only works when you’re lifting all the time.

(Ellenor Malik (spare me thy resistant starch spiel)) #18

Limiting protein to your body’s actual requirement is not essential but it helps a lot if you want to break a stall after losing more than about 30kg of weight.


I don’t experience anything but 3g/kg happens very rarely, for a single day. I do my best to keep it this way.