Ideal ratio of protein to fat?


(Richard Morris) #1

The two things are really not linked in a linear relationship. The protein you need to maintain your body, and the fat you use to fuel your total daily energy requirements - these are 2 mostly unrelated items.

No-one can tell you that your dietary fat must be a fixed ratio of your protein - because that will be wrong for almost everyone.

Protein requirement is a function of your lean body mass, if you know exactly what your LBM is then you can eat the RDI (0.84 g/kg) and be dialed in. If you don’t know your exact LBM, you can take a guess and aim for 1.0-1.5g/kg and be in the zone.

If you are not hyperinsulinemic and you don’t have kidney disease you can apparently err on the high side (up to 3.0g/kg LBM) without problems. You’ll burn it for energy, it’ll defray burning fat and you’ll make a few less ketones - but that’s mostly not an issue.

If you are hyperinsulinemic - too much protein will raise insulin which can be enough to inhibit lipolysis and stall weight loss. How much is too much depends on your insulin resistance.

You can certainly eat too much or too little Dietary Fat. The risk of eating too much plate fat is that you feel full, your body runs a bit hotter, your metabolic rate rises, and your body stores any extra energy left over.

So what is the minimum dietary fat you can eat? Well there is a limit of how much energy you can get from body fat - it can only deliver 0.9% of its energy every day. So you will need dietary fat at some point just to meet your energy requirements. If you are hyperinsulinaemic you may not be able to use any body fat at all until you lower your insulin.

The risk if you eat too little plate fat is that you get hungry, your body runs colder, your metabolic rate drops and your body will go looking for energy to meet it’s shortfall. If your body goes looking for energy, and it can’t get it from body fat, it will scavenge some from lean body mass.

If all that is too complicated the the simple version is eat 20g carbs, 1-1.5g protein/kg LBM, fat to satiety and let your body manage all the calculus. And if that stops working, lower your insulin further.


Macros - am I supposed to hit all numbers?
20:4 fasting
(Peter Barney) #2

I’m pretty active with my weekly exercise routine, lift heavy things 5 times a week running 4-5 mornings, fast 5kms upto 20km runs while watching the sun come up. My need for protein is quite high but since I have been tracking my blood glucose and ketones i see my body loves to pump out lots of insulin in response for a long time afterwards.

As you say @richard everyone is different and you have to find your own numbers that fit. Since going Keto i have kept protien to moderate but I’ve now increased my protein to 1.5-2g/kg keeping carbs as low under 20g as i can and not fearing the fat.

But i have reduced my eating window to just a couple of hours around my gym work outs, to great success. Keto just became easy again :grinning: as it was when I first started over 18 months ago.

I suppose my body has adjusted to running on fat and so my needs have changed since I started this woe. Performance after taking a frustrating dip initially has now increased and recovery times are faster than ever.

We all have to listen to our bodies and this forum is great for supplying information and others experiences, so that we can interpret our own signals.


(Gaby Abed) #3

Easy rule of thumb I use, hope it’s applicable here. I know people should tend to move away from percentages, and use absolute values instead, so this is more of a double check you’re getting a minimum amount of fat.

The rule is:
If Fat Grams >= (Carb Grams + Protein Grams), then Calories from fat will be at least 70% (okay, 69.2%, but close enough) :slight_smile:

So, for example, if your LBM = 73kg and you’re capped at 30 grams of carbs, to know you’re at at least 70% of calories from fat, your fat grams should be 92 (protein = 73kg * .84, carbs = 30).