“high protein” vs “low protein”
The lipophobics and the aminophobics are both talking past each other at strawmen.
The hysteria is not just humorous, it’s confusing and turning away novices.
This phony controversy causes people to recommend insane amounts of protein at BOTH ends of the spectrum.
Protein tends to be a passionate topic of discussion n the online macronutrient wars. So I thought it would be useful to set out arguments at both extremes of the ‘protein controversy’ and detail some responses to bring some balance. My hope is that this article will bring some clarity to the civil war in the low carb/keto community.
The TL:DR summary is:
- appetite is a reliable driver to make sure you get enough protein to suit your needs,
- our appetite decreases when we get enough protein,
- it’s hard to overeat protein because it’s hard to convert to energy, so the body doesn’t want more than it can use,
- most people get adequate protein without worrying about it too much,
- people who require a therapeutic ketogenic approach should pay attention to their diet to ensure that they don’t miss out on essential micronutrients while maintaining a low insulin load, and
- if you prioritise nutritious whole foods, you’re likely getting enough protein but not too much.
If you want more detail, read on! The arguments and responses of the two sides are outlined below. The article then concludes with some learnings and observations from the Nutrient Optimiser about how we can optimise protein intake to suit our goals and situation.
High protein bros
This section outlines the arguments and responses from the “high protein bro” extreme end of the debate.
“There is no such thing as too much protein.”
Refined protein supplements do not contain the same quantity of much vitamins, minerals or essential fatty acids as whole foods.
As shown in the plot of percentage protein vs nutrient score, a focus on obtaining adequate vitamins, minerals and essential fatty acids from whole foods typically leads to obtaining plenty of amino acids. Meanwhile, actively avoiding protein tends to dilute overall nutrient density in terms of vitamins and minerals.
The body typically down-regulates appetite before it consumes ‘too much protein’. It is physically difficult to eat ‘too much protein’ from whole foods (although hyperpalatable whey protein shakes may be another matter).
While protein is beneficial, we also need a balanced diet that provides the other vitamins and minerals (e.g. electrolytes that will enable the kidneys to maintain acid/base balance which is critical to insulin sensitivity which is hard to obtain from protein supplements).
In summary, it is possible to focus too much on protein to the point that you are missing out on other important micronutrients. Conversely though, if you chase micronutrients from whole foods you will get adequate amounts of protein.
“Fasting will cause you to lose muscle due to a lack of protein intake.”
A high-fat diet reduces the need for glucose and therefore the requirements for protein from gluconeogenesis decrease. Someone who is ‘fat adapted’ with lower insulin and blood glucose levels will also be more readily able to access their stored body fat for fuel.
The body defends lean muscle loss by upregulating appetite. People with more body fat and/or lower insulin levels will likely find fasting easier than people who are lean and/or have high insulin levels.
Fasting will drive autophagy, which is beneficial, to an extent. Fasting and feasting is a cyclic process of building and cleaning out. We need to balance both parts of the cycle. Humans generally do this well in the absence of hyper-palatable processed foods.
One of the benefits of fasting is that when you re-feed, your body will be more insulin sensitive so you will build back new muscle more efficiently with less protein and insulin required. People doing regular multi-day fasts should ensure their average protein intake is adequate over a number of days and not just on the days they eat.
You should target more nutritious foods on your eating days to ensure you are getting adequate nutrients over the long term. If your goal is to lose body fat, then re-feeding to satiety on very high-fat foods may be counterproductive in terms of fat loss and micronutrient sufficiency.
“Everyone needs to lift heavy weights and be jacked.”
Not everyone wants to look good with their shirt off or is willing to invest the dedication that it takes to have a six-pack. However, being active and having sufficient lean muscle mass is important to maintaining insulin sensitivity and delaying the diseases of ageing. Doing something is better than nothing. Having sufficient lean muscle mass is arguably better than manipulating macronutrients if your goal is glucose disposal and fat burning.
Low protein “ketonians”
This section outlines a number of arguments against ‘too much protein’ along with some responses.
“Too much protein will turn to glucose like chocolate cake in your bloodstream”
Protein can be converted to glucose via gluconeogenesis if there is no other fuel available. However, gluconeogenesis does not come easily, and the body only resorts to increased levels of gluconeogenesis above baseline levels in emergency situations. Gluconeogenesis yields only 2 ATP from 6 ATP.
“Too much protein is dangerous for your kidneys”
High levels of protein are only a concern if you have a pre-existing kidney issue, and even then not everyone is in agreement.
“Protein is expensive and a waste to use for fuel”
The fact that using protein for fuel is metabolically expensive can be beneficial if our goal is fat loss as it increases overall energy expenditure.  By contrast, fat and carbs are more efficient fuel sources. Higher levels of protein intake will drive satiety as well as being less efficient and cause more losses.
High protein foods are often financially expensive. Processed high fat and high carb foods are cheaper to produce and hence can have a higher markup applied to them. Thus, food companies tend to promote cheaper foods with a higher carb and/or fat content.
“Too much protein is dangerous for people with diabetes.”
People with diabetes convert more protein to glucose through uncontrolled gluconeogenesis (i.e. due to insulin resistance in Type 2 and a lack of insulin in Type 1). They also find it harder to build muscle due to a lack of insulin. Hence, people with diabetes may benefit from consuming more protein to maintain or gain muscle.
Conversely, people who are insulin sensitive may require less protein because they can use it more efficiently to build and repair muscle.
As shown in the chart below, people with diabetes (yellow lines) produce more insulin in response to protein than metabolically healthy people (white lines). Forcing more protein beyond satiety may make diabetes management more difficult. However, most people get the results they require from reducing carbohydrates. The fact that protein turns to glucose can be a useful hack for people with brittle diabetes who want to get their glucose without the aggressive swings that refined carbohydrates can provide.
“Too much protein will make it hard maintain healthy blood sugar levels because protein stimulates insulin and glucagon.”
Protein requires insulin to metabolise. Insulin also works to keep glycogen stored in the liver.
As shown in the charts below, an increase in protein in the diet typically forces out processed and refined carbohydrate and so decreases your insulin and glucose response to food.   [You can check out the interactive Tableau version of these charts here.]
People with Type 1 diabetes don’t have enough insulin to metabolise protein and maintain healthy blood sugars at the same time and hence require exogenous insulin.
People with Type 2 diabetes often have plenty of insulin but need to ‘invest’ their insulin wisely on metabolising protein to build muscles and repair their vital organs rather than ‘squandering it’ on refined carbohydrates.
People with hyperinsulinemia will often see their blood sugars decrease after a high protein meal as the insulin released to metabolise the protein also works to reduce their blood sugars.
If you see your blood sugars rise after a high protein meal you may have inadequate insulin. IF you have an insulin insufficiency, you may need to learn to accurately dose with insulin for protein rather than avoiding protein.
“High protein will shorten life due to excess mTOR stimulation.”
Humans need to balance growth (i.e. increased IGF-1, insulin and mTOR) with repair (i.e. autophagy, fasting and ketosis). Driving excess growth through unnatural means may not be beneficial for long-term health.
However, the research into protein restriction and longevity is either theoretical or in worms in a petri dish where they grew more slowly when protein and/or energy was restricted. Free-living humans typically don’t manage to voluntarily restrict energy intake. We seem to have an inbuilt drive to protect ourselves from a loss of muscle mass, depression (note: good nutrition, especially amino acids is crucial to brain function) and loss of sex drive, and generally feeling cold and miserable.
Longevity research in monkeys suggests that energy restriction or at least a reduction in modern processed foods is beneficial. However, there is no research in mammals that demonstrates that protein restriction extends lifespan or health span.
The low target protein values proposed by some for longevity (i.e. 0.6g/kg lean body mass or LBM) are practically impossible to achieve from whole foods without the addition of a significant amount of oils and refined fats and/or substantial calorie restriction to the point of rapid weight loss (e.g. check out the Nutrient Optimiser analysis of Dr Rosedale’s diet here).
There is a difference between lifespan and healthspan. Humans in the wild who are frail risk fractures and other complications related to muscle wasting and lethargy.
As shown in the chart below, there is an optimal balance between growth and wasting. Too much insulin and you grow to the point that you get complications of metabolic disease. Too little growth and you become frail, lose your muscle and bone strength then you may fall, break your hip and never get up again.
“Just eating protein won’t give you gainz!”
Yes indeed! You need to force an adaptive stress to cause muscle gains, not just eating protein. If you work out, you will likely crave more protein. This is natural and healthy and ensures that we can recover, adapt and get stronger.
“Overeating protein will make you fat.”
Excess consumption of any macronutrient will make you fat. However, eating more protein and fewer carbs and fat tends to increase satiety.
Research in resistance-trained athletes shows that overeating protein does not cause an increase in fat mass.  Research in sedentary adults shows that overeating protein causes a more favourable change in body composition than overeating the same amount of calories from fat and/or carbohydrate.
“Too much protein will lead to rabbit starvation.”
Healthy people can metabolise up to 3.5g/kg protein per day and digest up to 4.3g/kg per day. This makes sense in an evolutionary context (or even in more recent times before we had refrigerators) when there wouldn’t have been a regular supply of food but we would have needed to be able to use the food when we came across a big hunt after a long famine.
Theoretical research suggests there is no upper limit to protein intake to the point it is dangerous. However, the practical upper limit seems to be around 50% of energy intake. If you force extreme levels of protein, you get thirsty and pee out the excess protein.
Growing children and active people tend to crave higher levels of protein to build and repair their muscles (i.e. 10-year-old Bailan Jones, shown on the right here with his brother, who is a growing young man with Type 1 who consumes 4.4g/kg LBM).
If you’re obese and eat only lean protein, your body will be forced to use body fat for fuel. If you are very lean and eat nothing but very thin protein satiety will kick in and you will not have enough body fat to burn. This is dangerous and leads to death. So if you are already very lean and going to live in the wilderness with only wild rabbits to eat, make sure you take some butter. However, most people will have adequate body fat to use for fuel for a significant period of time before rabbit starvation would be an issue.
“If you’re not losing weight, you should cut your protein and your carbs and eat fat to satiety.”
Reducing processed carbs helps to lower insulin and stabilise blood sugars and helps a lot of people reduce their appetite and lose body fat.  However, not everyone reaches their optimal weight with this method.
LCHF / keto works until it doesn’t.
Many people find that they need to reduce dietary fat in addition to carbohydrates to ensure they burn body fat.
While reducing the insulin load of your diet to the point that we achieve healthy blood glucose levels often helps improve satiety, effective weight loss diets typically involve some permutation of reduced fat and/or carbs to achieve a reduction in energy intake.
Medical weight loss clinics typically use a version of a protein sparing modified fast which provides adequate protein to prevent loss of lean muscle mass while restricting carbohydrates and fat.  
People on a low carb or keto diet may have an increased requirement for protein due to the body’s increased reliance on protein for glucose compared to someone who is getting their glucose from carbohydrate. Protein is the most satiating macronutrient and eating more fat when your appetite is actually craving protein, or other nutrients may lead to excess energy intake.
“Too much protein will kick you out of ketosis and halt fat burning.”
Contrary to popular belief (which is often propagated by people marketing ketogenic products), ketosis is only one of a number of pathways that we burn fat.
Ketones (i.e. AcetoAcetate or AcAc) are produced when there we don’t have enough Oxaloacetate (OAA) to produce citrate in the Krebs cycle.
If you are consuming enough protein and/or carbs to provide OAA you will still burn fat but through the Krebs cycle rather than via ketogenesis. Thus, you may be “kicked out of ketosis” if you eat more protein but you’re still burning plenty of fat.
Most people will see ketones in their blood increase when fasting or restricting energy intake due to the lack of OAA as they burn body fat. As shown in the chart below, blood glucose levels decrease while BHB increases.
There are a number of beneficial processes (e.g. autophagy, increased NAD+, increase in sirtuins) that current during fasting/energy restriction that is associated with increased BHB. It is possible that many of the benefits related to BHB may actually be due to these other beneficial processes that occur in endogenous ketosis (i.e. it’s probably not the ketones).
We can force higher levels of BHB in the blood by eating more dietary fat and less protein and carbohydrates. In this case, high BHB may be an indication that you are eating more fat than can be burned in the Krebs cycle and it is building up in the blood. High levels of BHB in the blood do not mean you are achieving the same benefits via exogenous ketosis as we do in endogenous ketosis.
If your AcAc is not converted to BHB due to a low NAD+:NADH ratio you will tend to see more breath acetone (BrAce). If you do not have metabolic syndrome, you may see higher levels of BrAce (i.e. measured with the Ketonix) and lower levels of BHB in the blood. You should also be aware that exercise and an adequate intake of B vitamins in the diet will also increase your NAD+ levels and ‘kick you out of ketosis’.
Before you get caught up chasing ketones by whatever means possible, you should keep in mind that someone who is metabolically healthy and easily able to access their body fat stores for fuel (i.e. low insulin levels) will have lower overall levels of energy floating around in their blood (i.e. from blood glucose, ketones or free fatty acids). Higher levels of energy in the bloodstream is a sign of poor metabolic health and reduced ability to access and burn fat.
High levels of glucose lead to glycation. High levels of free fatty acids lead to oxidised LDL. High levels of glucose and free fatty acids tends to lead to glycated LDL. High levels of ketones can similarly lead to metabolic acidosis if not balanced with an adequate mineral intake which may also ‘kick you out of ketosis’.
Learnings from the Nutrient Optimiser
What is everyone else doing?
The Nutrient Optimiser Leaderboard demonstrates that low carbers have a wide range of protein intakes.
- The average fat intake of these people is 60%, with half the people between 54% and 68% calories. The average carb intake is 11% with half the people between 6 and 15%. So, we can see that this is generally a CLHF population.
- Half of the people lie between about 1.4 and 2.5g/kg LBM with an average of 2.1g/kg LBM. In terms of percentage, half of the people sit somewhere between 18 and 29% of energy from protein with an average of 24% energy from protein.
- Dr Rhonda Patrick, who is sitting at the top of the leaderboard, seems to be eating about 2.5g/kg LBM protein even though she says she is not particularly active and eats heaps of veggies.
- People who are active tend to eat more protein (e.g. Brianna, Andy Mant and Alex Leaf).
- “High” protein advocates Luis Villasenor of Ketogains and Dr Ted Naiman both seem to be consuming around 2.4g/kg LBM to support recovery from their higher activity exercise levels.
- People following a zero carb approach tend to be eating more protein (e.g. Shawn Baker at 6.1g/kg LBM and Amy on 3.3g/kg LBM) as more of their energy comes from animal food. Perhaps many of the satiety effects of a Zero Carb dietary approach are actually due to the high satiety effects of protein.
- The people with less than 1.0g/kg LBM tend to be relying on a significant amount of added fats and do not tend to achieve the highest overall nutrient score (see examples here, here and here).
What are the recommendations?
The very wide range of protein intake levels can be confusing. Some are outlined below for reference.
- In long-term fasting, we use about 0.4g/kg LBM protein from our body via gluconeogenesis.
- The Estimated Average Requirement is 0.68g/kg body weight for men to prevent protein related deficiencies and 0.6g/kg body weight for women. For a woman with 35% body fat, this equates to 0.92g/kg LBM as a minimum protein intake. (Note: These standard values are in the context of someone eating a conventional diet where they would typically be getting plenty of glucose from carbohydrates and are not particularly active, and protein requirements may be higher where someone is active and using some protein for glucose via gluconeogenesis.)
- The Recommended Daily Intake is 0.84g/kg body weight for men to prevent protein related deficiencies and 0.75g/kg body weight for women (Note: For a woman with 35% body fat this equates to 1.15g/kg LBM as a minimum for someone who is sedentary).
- Steve Phinney recommends 1.5 to 2.0g/kg reference body weight (see slide below from his recent presentation in Brisbane) which equates to around 1.7 to 2.2g/kg LBM for someone wanting to lose 10% of their body weight to achieve their ideal ‘reference weight’. This increased level allows for some glucose to come from protein via gluconeogenesis and allows adequate protein for people who are not eating carbs and active.
- Ketogains suggest 0.8 to 1.0g/lb LBM or 1.8 to 2.2g/kg LBM for people who are looking to maintain or build higher levels of muscle mass.
- Mainstream bodybuilding recommends 1.7 to 2.5g/lb body weight or 3.7 to 5.5g/kg body weight. For someone with 15% body fat, this equates to 4.3 to 6.4g/kg LBM!!!
What happens to micronutrients when we chase protein?
When I first started tinkering with nutrient density, I assumed that we would want to boost all the essential nutrients (i.e. similar to Dr Mat Lalonde’s approach). The chart below shows the nutrients provided when we prioritise foods that have higher amounts of all the essential micronutrients. The amino acids are shown in maroon.
The ‘problem’ with this array of foods is that, because protein is easy to obtain, this group of foods ends up being very high in protein! Even the “high protein bros” won’t be able to consume seventy percent of their energy from protein.
As you can see from the figure below, we typically can’t eat more than 50% of our energy from protein. However, satiety levels tend to be highest, and hence energy intake is the lowest at around 50% protein (dark blue area).
There is generally no need to prioritise amino acids because it is easy to meet the Recommended Daily Intake for amino acids if we eat whole foods.
Emphasise only harder to find nutrients
Rather than prioritising all the micronutrients, the chart below shows the micronutrient profile that we get if we prioritise the harder to obtain micronutrients (shown in yellow) without prioritising any of the amino acids (shown in maroon). (Note: Vitamin E and Pantothenic Acid haven’t been prioritised as the target levels are based on population averages rather than deficiency studies).
As you can see, we still get heaps of protein. However, we get a much better micronutrient profile in the vitamins and minerals because we are only prioritising the harder to find micronutrients.
Maximising nutrient intake while minimising energy intake appears to be central to reducing natural energy intake and minimising nutrient related cravings and bingeing. It’s not hard to see how we could reduce our energy intake eating these foods while still getting plenty of the essential micronutrients.
Highest protein foods
For comparison, the chart below shows the nutrient profile of the highest protein foods. It seems when we prioritise foods based on their protein content we end up missing out on a number of the vitamins and minerals. Thus, there appears to be a danger that we will miss out on micronutrients when we focus only on protein.
Do plant-based diets provide enough protein?
The one situation I have seen people not meeting the recommended daily intake levels for protein is people following a purely plant-based diet. In the nutrient profile shown below, Sidonie is only getting 11% of her calories from protein and you can see that leucine is not meeting the DRI levels while methionine and lysine are just meeting the minimum levels. This may be a legitimate concern for someone on a plant-based diet as amino acids tend to be less bioavailable from plans in comparison to animals.
Most ketogenic foods
The chart below shows the nutrient profile of the most ketogenic foods (i.e. the ones that require the lowest insulin by limiting carbs and moderating protein). It seems that, if you actually require therapeutic ketosis (i.e. to manage epilepsy, cancer, dementia or Alzheimer’s), you will need to pay particular attention to getting adequate micronutrients (i.e. notably, choline, folate, potassium, calcium and magnesium).
Lowest protein foods
And finally, the chart below shows the micronutrient profile if we actively avoid protein.
It seems that actively avoiding protein has a diabolical impact on the micronutrient profile of our food. However, when we focus on balancing our diet at a micronutrient level, everything else seems to work out pretty well.
So what should I eat?
With all the conflicting opinions it can be confusing to know what to eat.
In the end, it comes down to eat good food when hungry.
If we remove hyperpalatable processed foods, I think we’ll have a much better chance of being able to trust our appetite to guide us to the foods that will be good for us.
The food lists below have been prepared to provide the most nutrients while aligning with different goals (e.g. therapeutic ketosis, blood sugar control weight loss, maintenance or athletic performance). There are a whole lot of other lists in the Optimal Foods for YOU article that are tweaked to suit different goals.
Once you’re eating well and want to further refine your diet you want to check out the Nutrient Optimiser.