Why the obsession with protein in modern nutrition?

In My Humble Opinion
41

Actually, the above article concludes this:

A goal of this meta-analysis was to deliver evidence-based recommendations that could be readily translated. A crucial point is that even though the mean baseline protein intake for the 1863 participants was ~1.4 g protein/kg/day, which is 75% greater than the current US/Canadian recommended dietary allowance (RDA),78 an average supplementation of ~35 g protein/day still augmented RET-stimulated gain in FFM (figure 3) and 1RM strength (figure 2). Thus, consuming protein at the RDA of 0.8 g protein/kg/day appears insufficient for those who have the goal of gaining greater strength and FFM with RET. This conclusion is emphasised for older men79 and women80 81wishing to obtain strength and gain lean mass with RET and protein supplementation.

A recent retrospective analysis showed a ‘breakpoint’ for the stimulation of MPS when ingesting an isolated protein source at 0.24 g protein/kg and 0.40 g protein/kg in younger and older participants, respectively.14 Given the observation of a dose-responsive relationship between protein intake and MPS82–85 and the fact that MPS is aligned with muscle hypertrophy,13 we elected to use an identical two-segment regression approach between total daily protein intake and changes in FFM (figure 5) as has been done for changes in protein dose and MPS.14 Here we provide significant insight (using 42 study arms including 723 young and old participants with protein intakes ranging from 0.9 g protein/kg/day to 2.4 g protein/kg/day) by reporting an unadjusted plateau in RET-induced gains in FFM at 1.62 g protein/kg/day (95% CI: 1.03 to 2.20). These results are largely in congruence with previous narrative reviews that comment on the optimal nutritional strategies to augment skeletal muscle adaptation during RET.3 86 Given that the CI of this estimate spanned from 1.03 to 2.20, it may be prudent to recommend ~2.2 g protein/kg/d for those seeking to maximise resistance training-induced gains in FFM. Though we acknowledge that there are limitations to this approach, we propose that these findings are based on reasonable evidence and theory and provide a pragmatic estimate with an incumbent error that the reader could take into consideration.

42

I agree resistance training is certainly more important than increasing protein. Americans already eat a lot of this and no one complains of an epidemic of muscularity. Most of the benefit is from exercising. Still, the article concludes eating 1g/lb is reasonable given the confidence intervals depending on one’s goals and activities.

A lot of lifters are obsessed with “minimum protein required”. But losing fat or weight may require limiting calories and considering insulin effects. Protein also causes insulin release, but sugar usually more so. Eating more protein than the absolute minimum may not always be needed. It may be better than eating more carbs or fat instead, however, for some athletes. If hoping to build muscle, it is probably more effective to eat protein than getting most of your calories from sugar. Many of the recommendations for high protein intake seem to come from those involved with industry, a common situation with nutritional advice. Almost certainly they recommend excessive amounts. Of course your body is skilled in making use of what is available to it.

Of course meta-analyses obscure specific strength training methods, and excluding confounders like creatine (or less savoury supplements and enhancers) might limit the applicability of the results for some individuals.

A lot of “meathead logic” may not have great evidence, but it still works for many people. Similarly, a lot of emergency medicine has less robust evidence than one might hope, but it has been done that way for years and seems effective.

43

I pretty much agree with this.

There’s a lot of disagreement even among expert sources as to whether “we should be eating more protein” vs “we’re probably eating too miuch protein”. A lot depends on the individual, including age and kidney function (too much protein is bad for marginally functioning kidneys). There are also heart health and cancer risks associated with excess protein intake, particularly if red meat is a major source of that protein.

I’ll throw another thought-provoking article into the mix.

I misread that as liverwurst being a remedy for liver disease. Not if it’s from Boar’s Head. :slight_smile:

44

Lots of places offer tofu, veggie burgers, fish (which some people do not consider “meat”) or an egg-based option.

45

The conclusion that 2.20 is within the confidence interval so “why not?”, is as justifiable as saying 1.03 is within the interval and should be recommended. It is based on assumption that the only potential negative is by not having enough so err on the more side.

Another more recent analysis BTW:

The percentage change in muscle strength gradually increased with total protein intake and peaked at approximately 1.5 g/kg BW/d with resistance training (Fig. 2a). Muscle strength with resistance training increased by 0.72% (95% CI 0.40–1.04%) per 0.1 g/kg BW/d increase in protein intake up to 1.5 g/kg BW/d, but no further gains were observed thereafter. Without resistance training, there was only a fractional increase in muscle strength, which increased slightly with total protein intake up to 1.3 g/kg BW/d and gradually vanished after that (Fig. 2b).

Very interestingly the graphic shows a peak at about 1.5. It appears to drop off with more. I wouldn’t assume such is untrue.

Anyway. This portion of the discussion is for the specific subset of those strength training and wanting to maximize hypertrophy and/or strength gains, leaving no possible gain on the table. Most of us, include most of us who are very dedicated to our fitness, are not so worried about that.

46

Not the specific number but the laws of thermodynamics would say that you’re not going to get larger unless you’re at a surplus.

If you increase your volume, you might be able to lose some fat and build some muscle but that’s really going to be an upwards climb the more that you try to do it. Fundamentally, you can’t become bigger by lifting. Lifting doesn’t generate mass, it merely transitions it.

Your body is already at the size it’s going to be with your current protein intake and strength training volume. Whether that’s 1g per lb, 0.5g, or 1.5g, you’ve found homeostasis and you can only shrink or maintain with more fitness. Packing on muscle means taking your current intake and upping it.

47

Really physiology doesn’t work like that.

Hard to even know where to start with how that is wrong.

I’ll keep it very basic. Muscles can only net gain (always a balance of turnover each day, anabolism and catabolism, “net nitrogen balance”) so much each time period. Protein intake beyond that, and other protein turnover in the body, is used for energy. Your logic is about the same as saying you should water a seedling of a redwood with the volume of water that you want the adult tree to be.

Of course you need enough calories so that the protein is needed for energy instead of going to positive nitrogen balance.

48

Bodies are complicated, and can use a variety of nutrients to meet their needs. I eat a ton of protein (because all my favorite foods are protein) and I’m not huge, because i don’t do much of the kind of exercises that trigger muscles to get larger. I also have plenty of spare fat. I’m certain that i could maintain my current diet, and gain a lot of muscle mass if i exercised in the ways that stimulate muscle growth. The same calories that are currently supporting fatty tissue, or even being pooped away, could be turned into muscle. I suspect that if i took the right steroids, i could do it without even adding a lot of exercise. (I do engage in weight bearing exercises, just not the type and quantity that maximize muscle growth.)

I suspect that most Americans who have the leisure to worry about gaining muscle mass could do so without significantly increasing their protein intake. Americans eat a ton of protein. Some would need to increase their total calories so they didn’t burn the protein they are eating for energy. (I wouldn’t, that layer of subcutaneous day says that i get more than enough calories, too.)

49

Both statements (mine and yours) are, effectively, overly simplified.

If excess calories simply get burned then there’s no path to get fat and no path to bulking. I can see, in daily life, that there are fat people and there are muscle monsters. That theory is not true.

But, likewise, yes you’re not going to eat an extra 30lbs of protein, today, and wake up with 30lbs of muscle, newly added to your body, tomorrow. That’s also not true. (But very distant from what I said.)

Plants don’t grow big from watering, that’s true, but that’s because they’re made of primarily made of carbon and take carbon out of the air. And given a higher carbon ratio in the air, they do seem to grow larger. Humans are, likewise, mostly made of carbon but we get most of it from food and, in the presence of more food, we generally become larger for having consumed more of it.

People who carry heavy weights for 8 hours of the day (e.g. thru hikers) can stay slender at very high calorie counts but, for almost everyone else, your weight is effectively determined by your calorie intake and weight training simply determines what type of tissue it becomes on your skeleton. Yes, again, that’s a simplified view but it’s the most useful one for almost everyone.

My understanding is that we don’t properly understand that mechanism and that we are, to some extent, limited to fantasy explanations of the process.

But, to my understanding, our understanding is that our bodies are taking in a variety of information - how hard we’re working, how successful we are at finding food, what the macronutrient profile is of that food, etc. and determining how best to use it all. It may decide to pass it through, burn it as energy, add it as fat, add it as muscle, or some mix of all of those.

And on the other side, maintaining muscle requires energy; maintaining fat cells requires energy; repairing damaged muscles requires material; repairing degrading fat cells requires material. New cells can be built, repaired as they were, modified to be smaller, or modified to be bigger.

The human body uses all those stimuli and evolutionary programming to make those decisions. It can’t pull mass out of a parallel dimension, though. That’s not one of the choices.

There are mitigating factors like testosterone level, metabolism, etc. That’s going to vary the result and the maximums for individuals.

But you definitely can’t create something from nothing. There’s no 300lbs Strongman that’s eating 2000 calories a day. If you find that person, you’ve found someone that’s lying.

50

Gotta say that much of this discussion while interesting, is pretty theoretical. Protein is one of the most minor problems in the American diet. We all get enough and then some.

The main problem in the American diet is eating food that is absolutely terrible for one’s health and way too much of it, while hardly getting any exercise at all. Focusing on the protein amount of one’s diet is more a distraction from how unhealthy the rest of one’s diet is, than a useful thing to ponder.

If your diet consists mainly of whole grains, a little oil, and minimally processed vegetable and fruits, thinking seriously about protein sources and amounts would make some sense, of course.

51

Well, very few people aspire to be 300lbs of any body makeup. But i suspect there are a lot of Americans who could become much more muscular without changing their eating habits at all.

And i didn’t read

“Used for energy” as “burned away”, but rather, as added to the general calorie intake of the body, not specifically used as protein. So that excess protein can keep you warm, or fuel the repair of cells, or be packed away as fat, just like any other generic calorie you consume.

52

I don’t disagree with that. But you definitely can’t add mass, of any type, without a surplus - excusing some case like where your body hasn’t been digesting most of the food and it’s just been going right through you, and then you get a cure for that issue. Likewise, you might have effects like your metabolism showing down, etc. But those are just variations of switching from a lower to a higher amount of calorie intake.

53

For the subject of the OP this, and a focus on macro ratios at all, is the big point. The huge issue of the Standard American Diet (seriously referred to as SAD in the literature) is not the macro ratios. It is an excess of calories driven by processed foods that have low satiety and are made with the balance of sweet salty and fat that drives us to eat more even when satiated. A diet higher in less processed foods, less added sugars, more plant forward than the SAD, will almost always result in acceptable macros for all but very specific subgroups.

Yes. (Even if the metabolic pathways are indirect.) The amount of net synthesis of muscle is driven by the degree of the stimulus (resistance training) primarily, but can be constrained by not having enough of the raw material, the necessary amino acids and energy for the subject of this discussion. Above what the muscles can incorporate protein is broken down for parts and energy thrown into the mix. We do not store excess protein for later like we can glucose and fat so excess protein in face of a calorie surplus and the needs of that day result in more glucose and fat getting stored.

That’s the basic mantra: building muscle requires the stimulus number one; adequate protein intake to allow response to the stimulus number two; and energy available to put to growth in addition to calories burned by activity, daily function, and maintenance, number three.

The last is practically understood as calories surplus, and for most seriously focused on hypertrophy training that’s how it works, bulk then cut, but it can be done with the extra energy available coming from fat stores. For most of us, not so seriously focused on hypertrophy but wanting some mass and strength and a healthy body composition, resistance training with moderate protein intake achievable with a basic healthy nutrition plan, will do the job.

54

Bodybuilders will always talk protein. But the question was about the obsession.

This has already been answered, but again:

  1. Most people don’t understand biochemistry, but protein=muscle is easy to understand, even if it is overstated (even if you strength train).
  2. Most men would like bigger muscles and to be stronger; and many women also are now realizing strength training helps them look and feel better.
  3. Lots of people have read books by Attia or Sinclair and think muscles and exercise allow people to live longer and do more.
  4. Most people think meat tastes good.
  5. Protein is easy to add to many snacks, and you can charge a hefty premium.
  6. People know protein is filling. People want to lose weight due to cultural programming. More protein may equal better body composition?
  7. Fat has long been seen as bad; now sugar is. What else you gonna eat?
  8. A sociopolitical reaction to gender roles or vegan diets for some? Masculinity! Paleo cavemen! The Rock is my hero….
55

Well to be fair none of that applies to the OP. The OP is a self-described “fat middle aged man trying to eat healthily” perplexed why a “qualified nutritionist” is so fixated on protein macros.

He and his wife are not focused on building big muscles.

The “protein is filling” may be part of the nutritionist’s mindset. Especially compared to processed crap and refined carbs.

The “what else you gonna eat” than sugar and fat is of course real foods including some with high fiber: vegetables, fruits, legumes, seeds, nuts, whole grains, dairy, fish, etc. The protein will be there automatically as part of the mix.

The nutritionist is likely not going caveman on them. (Although there is debate that such a diet may be more caveman than many so called Paleo diets are …)

56

Yeah, people tend to ignore the “gatherer” half of “hunter-gatherer”.

57

To be fair, plenty of it applies to the OP. Why did he see a nutritionist? Possibly since he describes himself as fat and wishes to eat healthier. Why is the nutritionist obsessed with protein? Possibly since it is filling, in most of the healthy foods you mention, eating it might allow satiety with fewer calories, it is more nutritious than what the average American snacks on, 95% of Americans snack adding 400-500 calories per day, and most of these snacks are high in sugar and low in nutrients and protein.

I think equating people to calorimeters was always an enormous simplification. I doubt the nutritionist just recommended the healthy foods you mentioned, which you might be able to eat ad libitum. I suspect the nutritionist broke things down into the usual mix of calories from protein, complex carbohydrates, sugars and various types of fat. And recommended increasing fiber and reducing fats and carbohydrates for weight loss. Leaving an emphasis on protein. Most nutritionists I know also exercise heavily, and mentioning those benefits is… hardly a stretch.i

58

Those people would be men, since there’s a big masculine romance about hunting. But foraged roots, stems, nuts, seeds, and grains would almost always be a large if not the major part of non-agricultural people’s calories.

59

It’s still terrible advice, even if it was followed up with advice about avoiding snacks and reducing sugar, that wasn’t what she led with, the main takeaway (as reported by my wife) was “eat more protein”. That’s flat out bad nutrition advice, my wife gets plenty of protein in her diet (and unlike me not too much sugar or carbs, she is in much better shape than me, she just had a baby last year, an excuse I don’t have despite appearance to the contrary :slight_smile: )

Personally I think a big part of it is that food manufacturers can chuck protein into terrible high-sugar high-sodium processed crap, and the slap a big sign in the front saying “high in protein”. So they love this obsession with protein and are doing everything they can ensure it persists

60

I think you are right.