Diets High Protein, High Fats, Low Fats… What’s The Difference?

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I love it when you guys ask questions!  Here’s an awesome question I received through Facebook!  This post actually turned into a much longer one than I originally expected, so sit back and take out your notebooks **smile**.  I have A LOT to say on this topic.


Q: What’s the difference between a diet of high fats and high protein vs. a diet of low fats and high protein?  Does one diet vs. the other have different effects on the body?   Hope this makes sense…. 


A:  Thanks for such a great question.  I think a lot of people have these same questions regarding which diet is “best” when it comes to getting real results.

First let’s address one thing.  If weight loss is your goal, the most important component in that equation is that you are in a negative energy balance.  That simply means that you are either taking in less calories than your body needs to maintain its weight, or you are expending more calories than your body needs to maintain its weight, or the best scenario, a combination of the two.  On very basic terms this is what leads to weight loss.  Now, for our purposes, and what I like to get across to all of you is that “weight loss” in and of itself isn’t our main goal, fat loss is.  And the scale doesn’t always determine that.  So let’s continue this “conversation” with fat loss in mind.

So at the end of the day, we can come to the conclusion that weight loss is based off of being in a caloric deficit that comes from a combination of a decrease in food intake, and an increase in caloric expenditure through activity (exercise).  However, where those calories come from can have a large effect on what is lost (how much of that weight is actual fat, or muscle tissue), and can even effect HOW YOU TRAIN.

High Protein and Fat Diets:

The high protein diet has gotten its share of the spotlight in the mainstream by way of the Atkins Diet, but since its release, there have been a million other diets that follow a similar kind of protocol.  These diets are basically ketogenic diets in one form or another.  Interestingly enough, it was first developed in the 1920s as a means to helping children with severe epilepsy to control seizures.  It included a set up where just enough protein was provided for growth and repair, starchy carbs were nearly eliminated from the diet, and fats were introduced in high amounts to maintain enough calories for the person’s height, weight, gender, etc.  Let’s stop and think about this from a nutritional standpoint for a minute.  There are two main sources of energy that the body prefers to use under perfect conditions.  Those two main sources are carbohydrates (the primary source) and fats (the secondary source).  So if you eliminate or lower one, you have to RAISE the other.  Which is why high protein diets tend to be inherently and significantly high in fats.  Conversely, higher carbohydrate diets typically are lower in fat.  If you lower, or in some extreme cases nearly eliminate, one you MUST raise the other for the body to at least “attempt” to properly function.

There is a third source of energy that the body can use in the absence of carbs, and that source is ketones.  Ketosis is a state where the body converts fat into ketones that the brain can use for fuel when glucose levels are low.  The only time the body needs to create and use large quantities of ketones is when insufficient carbs are available.  And what’s the best way to make all of this happen?  You guessed it…  A KETOGENIC DIET!  Or basically, a high protein/high fat diet.  Typically, the body will enter ketosis at levels below 100g of carbs/day.  And if you think using those tester strips will help you to determine if you’re in ketosis or not, you’re wrong!  The only time excess ketones will show up in the urine is when the blood has high levels of them.  You can be well into ketosis without the strips showing you as positively being there.  If you are on a diet consisting of you eating 100g of carbs or less per day, you can just about bet your bottom dollar that you ARE in fact in ketosis.

Another thing to make note of with this diet is that carbs ARE IN FACT produced…  So you will still have traces of glucose in your body thanks to a very expensive process called gluconeogenesis.  Basically as it sounds, it’s the creation of glucose through non carbohydrate sources…  And where do you think that comes from?  If you guessed PROTEIN, you’re right that’s one source (fats, namely triglycerides, are another).  The protein you’ve consumed can/will essentially be broken down to glucose since the body cannot store excess protein as fat.  You either pee it out, or convert it to carbs and burn it off.  However if you’re not eating enough protein on this diet, the body will gladly take it from your lean body mass.  No bueno!

Ok now that you know the stuffy sciencey part, let’s talk about how this can effect the body.  There have been several studies that show that individuals on a high protein/high fat diet tend to lose more overall fat than those on a diet that has a higher carb and lower fat intake.  These same studies also tend to come to the conclusion that many people have been able to not only maintain their lean body mass, but some MAY increase it when training is added to the equation.

Other studies have also interestingly shown that some participants may lose less SCALE WEIGHT on a high protein/fat diet than those on a high carb/low fat diet, however the overall FAT LOSS IS GREATER for those on the high protein/fat diet.  So the alluring potential of the short term success of a ketogenic diet glitters like gold.  However when most people go on a journey to lose weight, they have in mind to not only restrict calories, but to also train like madwomen (or men).  And this is where trouble can set in.

If you’re not getting in enough calories or adequate amounts of carbs and protein for the level of activity that you’re doing, you can stand to lose LBM.  Increased amounts of cardio and high intensity training while on a ketogenic type of diet can have a negative effect in the long term when it comes to hormonal regulation directly related to metabolism.  You can be potentially setting yourself up for further problems down the line that can actually HAMPER your efforts to lose weight.  In fact these negative effects can become so severe that you can actually begin GAINING WEIGHT or finding it much harder to take off weight that may have easily come off in the past.

Any diet where you restrict one macro over the over has a greater failure rate over the long term as you’re not really teaching yourself healthy habits that can be maintained once your goal is reached.  So it would be wiser to follow a more moderate and realistic approach from the get go instead of trying another “fad” type of approach.

Now understand that I’m not saying that a low carb/high protein and fat approach can’t be a tactic that is used at various points in a diet cycle to elicit a greater fat loss response.  I would be lying if I said that I’ve never used the approach at one point or another myself, however, it’s never a means to an end, only a step along the way.  Additionally, training is greatly effected on this kind of plan.  The body favors carbohydrates as its main source of fuel for higher intensity training.  It also prefers it for fueling any kind of longer duration kind of work.  Screw a bunch of the “fat burning zone.”  That’s a bunch of hogwash.  Raise your HR above anything beyond sitting on your butt reading this screen, you’ll be requiring glucose.  So wouldn’t it make sense to provide your body with the energy it needs to do work, energy that will supply you with the ability to work harder and hence lead to greater amounts of fat loss?  I would think so.

And lastly if you take a look at any of the studies I’ve referenced below (and these are just a few of MANY) at the end of the day, it is still OVERALL CALORIES that dictate weight loss.  You can create the same kind of fat loss effects from a diet that lends to a higher carbohydrate ratio.  In the long term, which is what you should always be considering, you’ll walk away with a more realistic approach that can help you to better maintain the weight you’ve lost once you’ve reached your goal.

High Protein Low Fat Diet

As discussed above, if one fuel source is lowered to a great degree, another has to take its place in order to meet caloric needs.  In this case you have a higher amount of protein, assuming a moderate amount of carbs, and a low amount of fat.  There are actually quite a few studies that have looked closer at this diet set up against something like a high carb/low fat approach and has found that although some greater amounts of fat loss can be seen with the high protein/low fat diet, it isn’t so great that it makes one better than the other.

I think what the problem is in both this kind of approach, and also with the ketogenic approach, there is this “demonization” of carbohydrates.  Carbs have gotten such a horrible wrap by the diet industry that people are afraid to eat them, so they’ll go about any ole way they can to rely on the “miracle macro” protein.  However when you begin to fully understand the role that carbs play in the body, how much the body does rely on them (in the form of glucose when broken down and utilized, it’s stored however as glycogen in the liver and muscle tissue) then you can start to let go of the fear that they make you “fat.”

So What’s A Gal To Do?

Well first off, forget the fads and get down to the basics.  The smartest way to approach your fat loss journey is to set up a plan that includes ALL macronutrients (and micronutrients as well – your vitamins and minerals).  Your food choices should be of “clean”, healthy, and whole grain sources.  There is room for a treat here and there, however the greater portion of your diet should be from nutritious sources.  I always like to keep the “90/10” rule in mind.  90% clean and whole foods, 10% of the “cheats.”  In this way, you get to give yourself realistic freedom to enjoy the process of changing your body without feeling restrictive or boxed in which only sets you up for failure down the line.

Figuring Out Calories And A Basic Macro Breakdown Approach

(We currently have an awesome Macro and Calorie Calculator on our website available in the members section. It takes a more specific and scientific approach to factoring totals for the individual. To access that calculator and more great tools click here to join.)

In figuring out caloric levels for fat loss I like to suggest something very basic to the lay person:

Multiply your BW by 14 or 15 (14 if you are more sedentary during your day, 15 if you are more active) and that will give you a rough amount of maintenance cals for your current stature.  Then subtract 250-500 cals from that (depending on your lifestyle, if you’re more active, subtract less, if you’re not as active, subtract more), and this will give you a good starting deficit in which you can begin to build a plan.

For your macronutrient breakdown, again keep it simple:

Protein – if you’re doing any kind of weight training or exercise, you want to multiply your BWx1 and that will give you the amount of GRAMS per day you should eat in protein.  If you’re less active or a little more on the overweight side, then the multiplier can be .8xBW.

Fats – now remember that this will vary based upon how many carbs you’ll be getting in.  For our purposes let’s try a low/moderate fat amount for our plan and have you between 45-50g/day to start.  You can also simply adjust fat so that it is about 25-30% of your total intake, whichever you prefer.  But you can easily adjust this as you see how your body responds. Keep in mind fat keeps you satiated, so if you lower this too much, then you can stand to be starving almost all of the time.

Carbs – the remainder of your calories will come from carbs.

Let’s now use me as an example.  I’m currently at about 140 lbs at the time of this writing.  And my goal is to lose about 10lbs, and I’d like to do that on average at about 1 lb/week.  So I’m going to figure out what my starting numbers should be for my diet.

140×15 = 2100 cals to maintain my weight (starting a little on the higher end since I workout and I’m on my feet most of the day).

2100-500 (I want my diet to do the work for me, and the training to add a small maintainable amount of caloric burn)=  1600 cals – This should have me losing at a rate of 1 lb a week from diet alone.  **You can choose less of a deficit here and just make up the rest with exercise if you wish.  So you can choose, for example, to instead create a deficit of 250 cals from food daily, and 250 from exercise daily.**

So I have 1600 cals to play with for my macros.

Protein – 140*1 = 140g/day.  There are 4 calories per gram of protein, so that is a total of 560 cals per day

Fat – I’m going to keep this at 50g/day.  There are 9 calories per gram of fat, so that’s a total of 450 cals per day.

Carbs – There are 4 calories per gram of carbs.  The calorie totals of my protein and fats combined is 1010 calories.  To figure out my carbs, I’ll subtract this from my daily deficit total.  So, 1600-1010= 590 cals.  I’ll now take this can divide by 4 (590/4) = 148g per day (rounded up from 147.5).

Now these numbers are simply starting points.  So you take them, try them out for 2 weeks, see how your body responds, and then adjust accordingly.  You can choose to change any of the variables in the equation.  So if I want to go with a little less carbs, then I’d go ahead and lower it, but adjust fats and/or protein (increase them) to meet caloric requirements accordingly to stay around 1600/day.  You can always just increase caloric burn through exercise as a means to create a greater deficit rather than restricting calories further.  I always say to start CONSERVATIVELY and FEED YOUR BODY rather going straight for absolute restriction.  You can always adjust when you start off with more than enough than not enough at all.  Plus wouldn’t you rather EAT MORE and TRAIN HARDER/SMARTER to see body transformation than to starve your way thin?

Keep in mind again, the equation above doesn’t lend to specific metabolism, training protocol, lifestyle, and a host of other factors that will effect fat loss and required calories.  However it’s a SANE starting point in which you can change as needed.  Experiment, apply the principles, and change it based upon your specific needs and how your body responds.


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Last AR, Wilson SA (June 2006). “Low-carbohydrate diets”. American Family Physician 73 (11): 1942–8.

A critique of low-carbohydrate ketogenic weight reduction regimens. A review of Dr. Atkins’ diet revolution., Journal of the American Medical Association, 1973

Farnsworth E, Luscombe ND, Noakes M, Wittert G, Argyiou E, Clifton PM. Effect of a high-protein, energy-restricted diet on body composition, glycemic control, and lipid concentrations in overweight and obese hyperinsulinemic men and women. Am J Clin Nutr. 2003 Jul;78(1):31-9

High-Protein Diets, American Heart Association, 14 March 2008

Skov AR, Toubro S, Ronn B, Holm L, Astrup A.Randomized trial on protein vs carbohydrate in ad libitum fat reduced diet for the treatment of obesity. Int J Obes Relat Metab Disord. 1999 May;23(5):528-36

Brehm BJ, Seeley RJ, Daniels SR, D’Alessio DA. A randomized trial comparing a very low carbohydrate diet and a calorie-restricted low fat diet on body weight and cardiovascular risk factors in healthy women. J Clin Endocrinol Metab. 2003 Apr;88(4):1617-23.

Johnston CS, Tjonn SL, Swan PD. High-protein, low-fat diets are effective for weight loss and favorably alter biomarkers in healthy adults. J Nutr. 2004 Mar;134(3):586-91. PMID: 14988451

Noakes M, Keogh JB, Foster PR, Clifton PM. Effect of an energy-restricted, high-protein, low-fat diet relative to a conventional high-carbohydrate, low-fat diet on weight loss, body composition, nutritional status, and markers of cardiovascular health in obese women. Am J Clin Nutr. 2005 Jun;81(6):1298-306. PMID: 15941879

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4 replies on “Diets High Protein, High Fats, Low Fats… What’s The Difference?

  • Bettina Brandon

    Hello Roxie,
    really enjoying all the information on your site. Very detailed, helpful and informative.
    Question…you would ever consider writing meal plans? I am eating my 6x meals a day but find it hard sometimes to find the right balance on good carbs and protein. Nor to decide each week what to include in my meal plans / what to cook / what to eat? What do you consume daily? How do you decide each week what to eat? Do you make your meals on the fly or do you plan week by week? So far I plan my meals week by week. Basically Sundays I spend 3 hours prepping, cooking, measuring, dividing and calculating my carbs and protein for the week. Searching for some guidance? Maybe it’s the wrong way I am approaching this. But I work a 6am-5pm / 10 hour job and hit the gym after work 5x a week and Sundays seems to be the best day to plan the meals ahead.

    Thank you for reading my message. Thank you for your kind response.
    Only the best to you,
    you are truely and inspiration.
    Thank you, BB :)

  • Kauisha

    Thanks so much for sharing this very detailed explanation. I have been following you ever since you were working with LBC and I am very impressed with your dedication and I really do admire you. I am always proud to see sistas doing their thing when it comes to health and fitness and keeping themselves in shape. I will share this with friends who are looking to get lean.

  • Roxie

    Kauisha thank you SO much for following along with me for this long girl! Yes I love being an example for women, particularly women of color to make health a priority. If you take care of the inside, the outside will fall into place.

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