Protein Intake While Dieting – Q&A

Question: You refer to “adequate protein intake” as important, but what do you consider adequate? In my case — calorie restriction of ~750-1000 kcals below BMR coupled with regular strength training? Is there a percentage of intake you consider ideal, and is it higher while dieting versus maintenance (to prevent muscle loss during times of restriction)?

Answer: The above question actually came through in the comments section of Exercise and Weight/Fat Loss: Part 2 and I thought it was important enough to address explicitly since it’s a place where I still see many mainstream diets and dieters making mistakes.   It’s worth noting that bodybuilders and other strength athletes have been promoting higher protein intakes while dieting for decades and this is yet another place where modern science has ended up validating those beliefs many years after the fact.

The question of adequate protein under different conditions is one that has a long history of debate, the issue of maintenance requirements as well as protein intakes for athletes is still highly debated with science on both sides of the story (for details you can refer to The Protein Book).

With regards dieting specifically, this was a topic of much study in the 60’s and 70’s as researchers started looking past the simple issue of weight loss and into that of changes in body composition; the goal moved from weight loss per se to that of generating fat loss while minimizing lean body mass and muscle mass loss.

After much toing and froing and research had been done it was eventually found that a protein intake of about 1.5 g/kg of lean body mass (LBM; note that researchers actually used Ideal Body Weight but this is a rough proxy for LBM) was necessary to spare LBM losses in a non-training obese individual consuming low calories.

This is about double the DRI for protein (at 0.8 g/kg) at maintenance calories.  So for an overweight individual at say 200 pounds and 30% body fat (this would give them an LBM of 140 lbs or 63 kg), that would be a protein intake of 95 grams of protein per day.   Please note that this value is simply a minimum and dieters may still find that higher protein intakes are beneficial from a hunger blunting effect or what have you (see below).

In that context, I’d mention that at least one of the studies I referred to in Exercise and Weight/Fat Loss: Part 2 that found no benefit of resistance training gave something like 40 grams of protein to the subjects; far less than necessary or adequate.  So it’s no surprise that no protein sparing effect of exercise was seen; the diet was inadequate in the first place.

It’s worth noting that more recent research supports further benefits of increased protein intakes while dieting, beyond simple lean body mass maintenance.  Protein is the most filling nutrient (meaning that higher protein intakes tend to control hunger better) and studies have found that higher protein intakes can help to stabilize blood sugar levels while dieting which has benefits from both an energy level and appetite standpoint.  Protein high in the amino acid leucine (with the dairy proteins whey and casein being the two proteins highest in leucine) seem to have extra benefit in this regard.

Now, as individuals get leaner, protein requirement tend to go up further for reasons discussed in other articles on this site.  As well, regular training tends to further increase protein requirements.  So lean athletes trying to lose fat while sparing lean body mass loss need even higher protein intakes than this.  And we’ve known for decades now that caloric intake per se tends to impact on protein requirements; as caloric intake goes down, protein requirements go up. And vice versa.

While less data on this group is available, bodybuilders and athletes have long used a protein intake of 2.2 g/kg (1 g/lb) lean body mass as a generalized intake level and as folks get very lean, intakes of 3.3 g/kg (1.5 g/lb) of lean body mass may be required to stave off muscle loss while dieting.  In some very extreme cases, such as the near protein only diet approach of my own Rapid Fat Loss Handbook even higher protein intakes may be required for very lean individuals.

So basically we have an intake continuum ranging from about 1.5 g/kg (0.68 g/lb) as a minimum for the obese non-training individual up to a high of around 3.3 g/kg (1.5 g/lb) of protein per pound of lean body mass for very lean heavily training athletes or bodybuilders with middle ground values being found in between those two extremes.  You’ll note that I didn’t put any of those values in terms of percentages for reasons discussed in Diet Percentages: Part 1 and Diet Percentages: Part 2.

So that’s what I mean by ‘adequate protein on a diet’ when I use that phrase.  It’s context dependent with the primary variables being body fat percentage (as this goes up, protein requirements go down), caloric intake (as caloric intake goes down, protein requirements go up and vice versa), and activity (with regular activity generally increasing protein requirements).



14 thoughts on “Protein Intake While Dieting – Q&A

  1. This is interesting in that it shows the continuum aspect of protein intake. Most fitness professionals simply state 1-1.5 g/ pound of body mass, which works as a blanket statement, but not for the individual.

    I aim for 1 g per pound, but if I wanted to reduce calories further could I drop this slightly? Protein foods tend to carry some extra calories and I don’t like relying on shakes so cutting slightly on protein could reduce calories more. One reason I’m asking is because it seems like a good bit of the recommendation to eat 1-1.5 g/lb is based on controlling appetite and whatnot, but I almost never have an issue with being extremely hungry on a diet (I’m lucky, I know).

    Summed up, since controlling hunger isn’t an issue for me, could I drop protein slightly to reduce calories, but still eat enough to get the physiological requirements to hold onto muscle?

  2. What a fantastic surprise to see my question answered in such detail! Thank you so much for taking the time to share your thoughts on the subject.

    I have Rapid Fat Loss Handbook and decided against that strategy as simply not practical for me (I’m in no particular rush to get to my ideal weight, and frankly, don’t have the discipline.) Your writing on protein in that book is what lead me back to your site and to ask this question, and I’m glad I did. As a vegetarian who gets the majority of her calories from fruits and vegetables, my protein intake is especially low. Obviously I don’t want to lose any more muscle than necessary so I intend to review this article carefully.

    Thanks again!

  3. Very thoroughly said, thanks!

    However, how would steroids affect protein intake while dieting? Would protein be lowered for maximum fat loss?

  4. Hi Lyle,

    Could we please have an answer on Tim’s question above?
    As a person is getting leaner and leaner, is it more important to raise protein (to spare LBM) or drop calories (increasing the caloric deficit to actually keep losing weight) ?


  5. Very good information. I’ve personally went from doing nothing to some simple little workout DVD’s, which include cardio and some weight training. I’ve also been adding a post workout whey protein shake after the weightlifting sessions.

    A month prior I was at 200lbs and 30% body fat at least from best estimates, but I’ve been trying to keep my protein intake up around that 100g range, especially on weight training days.

    I’ve been surprised by two things while taking protein shakes. First thing is that it does make you “fuller” and when you feel like you are not starved you don’t make rash decisions when it comes to meal time. Second, I’ve truly noticed a decrease in DOMS and faster strength recovery after an intense session.

    My blood pressure and resting pulse rate have dropped as well. I’m amazed at what a little work and eating can do.

    BP & heart rate before: 139/90 w/ resting pulse of 62
    BP & heart rate current: 127/68 w/ resting pulse of 51

    My scale tells me I’ve only lost 4 lbs, but my wife sees and feels the difference and I notice a difference.

  6. Tim & Nick;

    read this part:

    “Now, as individuals get leaner, protein requirement tend to go up further for reasons discussed in other articles on this site. As well, regular training tends to further increase protein requirements. So lean athletes trying to lose fat while sparing lean body mass loss need even higher protein intakes than this. And we’ve known for decades now that caloric intake per se tends to impact on protein requirements; as caloric intake goes down, protein requirements go up. And vice versa.”

    again – directly answers your question.

  7. Yeah, it doesn’t actually.

    I know when protein needs increase from a physiological stand point. My question was whether the amount recommended by most fitness professionals of 1-1.5 g / lb could be reduced if hunger wasn’t an issue since a primary reason for this amount is satiety.

    If .68 g / lb spared lean mass in non-training dieting obese, then obviously the requirement for a training lean person like myself would be higher, but my question is if physiologically it needs to be as high as 1-1.5 g / lb BW.

    Even if I wasn’t going to reduce calories via decreasing my protein intake slightly, I could add some carbs in (since with that much protein, a good bit of the glucogenic aminos would end up getting convert to glucose anyways – skip the middle man and allow me to eat more carbs).

    Either way there’s a difference between physiological requirements and recommended intakes for psychological issues (like hunger). That’s what my question refers to.

  8. Hi Lyle,

    I have been experimenting with alternating cutting and building phases. I have learned to appreciate both the complexity and the challenges posed by a goal of becoming very lean after having dieted down about 70 lbs of body fat. I am about 10% body fat now and have been very concerned about muscle loss. I am at the point where I think I am going to just use the best techniques I have learned from from Tom Venuto, you and others and just accept the results. Meaning that if I lose some LBM (muscle) in my efforts to cut to 5% body fat, then I will just accept that for now. Then I can look at some other strategies for putting on more muscle, with a minimum of fat gain. This truly is a tricky little process. Hope you are well. Have a great summer.


  9. Tim-

    I think the issue of how much protein to ingest is not an issue of satiety and is directly an issue about what the body needs to maintain LBM.

    What Lyle is trying to get at (correct me if I’m wrong), is that as you get leaner, your body REQUIRES more protein to maintain that LBM.

    Also, personal opinion, I think if you want to reduce your calorie intake, you probably need to cut all the carbs out and perhaps think about focusing on protein sources that have less carbs (i.e. go for plain chicken breast, rather than peanut butter).

    Just some thoughts. Good luck! 🙂

  10. I understand that the physiologic requirements go up when getting leaner. Again, not what I’m asking. Yes eating more lean protein and cutting carbs is safer in the view of sparing lean mass because it ensures you get all the protein you need.

    My question is simply about the total amount and whether 1-1.5 g/lb is necessary physiologically when dieting, not whether requirements increase when dieting or when getting to low body fat. Simply what is physiologically necessary, not taking satiety or anything else into account here, and not worrying about playing it safe?

    In all reality this question is more theoretical since I’ll probably stick slightly higher with protein to be safe, but people still seem to be misinterpreting my question.

  11. Hi Lyle!

    For some weeks I have been reading all of your articles I could, and I’m very interested in protein intake in fat loss. I have read that we can improve fat losing consuming more less CHO and elevating fatt intake. But in some articles you have said that it’s a question of availability, if we consume more CHO, our body will burn more CHO and less fat, and and vice versa with fat. Now comes my question, and if we consume more protein than CHO and fat? Now I’m consuming 150g of CHO, 230g of protein (which 200 are from animal source) and 70-80 of fat, which will be 2200-2300 kcal per day. I’m consuming more kcal from protein than fat or CHO, and more kcal from fat than CHO but… should I have to consume more kcal from fat than protein and CHO to note this effect I refered above?

    Can you clarify my issue? thanks!

    You’re the best, my best wishes! Don’t stop doing your bests works

  12. Increased protein intake reduces lean body mass loss during weight loss in athletes.

    Mettler S, Mitchell N, Tipton KD.

    School of Sport and Exercise Sciences, University of Birmingham, Birmingham, United Kingdom.

    PURPOSE: To examine the influence of dietary protein on lean body mass loss and performance during short-term hypoenergetic weight loss in athletes. METHODS: In a parallel design, 20 young healthy resistance-trained athletes were examined for energy expenditure for 1 wk and fed a mixed diet (15% protein, 100% energy) in the second week followed by a hypoenergetic diet (60% of the habitual energy intake), containing either 15% (approximately 1.0 g x kg(-1)) protein (control group, n = 10; CP) or 35% (approximately 2.3 g x kg(-1)) protein (high-protein group, n = 10; HP) for 2 wk. Subjects continued their habitual training throughout the study. Total, lean body, and fat mass, performance (squat jump, maximal isometric leg extension, one-repetition maximum (1RM) bench press, muscle endurance bench press, and 30-s Wingate test) and fasting blood samples (glucose, nonesterified fatty acids (NEFA), glycerol, urea, cortisol, free testosterone, free Insulin-like growth factor-1 (IGF-1), and growth hormone), and psychologic measures were examined at the end of each of the 4 wk. RESULTS: Total (-3.0 +/- 0.4 and -1.5 +/- 0.3 kg for the CP and HP, respectively, P = 0.036) and lean body mass loss (-1.6 +/- 0.3 and -0.3 +/- 0.3 kg, P = 0.006) were significantly larger in the CP compared with those in the HP. Fat loss, performance, and most blood parameters were not influenced by the diet. Urea was higher in HP, and NEFA and urea showed a group x time interaction. Fatigue ratings and “worse than normal” scores on the Daily Analysis of Life Demands for Athletes were higher in HP. CONCLUSIONS: These results indicate that approximately 2.3 g x kg(-1) or approximately 35% protein was significantly superior to approximately 1.0 g x kg(-1) or approximately 15% energy protein for maintenance of lean body mass in young healthy athletes during short-term hypoenergetic weight loss.

  13. I’m 162 lbs, unfit, sedentary woman, and have 42% body fat. That puts my LBM at 94 lbs. However, my ideal body weight is 130 lbs. So the difference between using LBM and ideal body weight in this calculation is significant. Using LBM, 1.5 g/kg would be 64 g protein. Using my ideal body weight, it would be 88 g. What is the study / review that arrived at 1.5 g/kg anyway?

Leave a Comment