How Much Protein Should You Have a Day? (+ Keto Protein Mistakes) • Prof Stuart Phillips

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Professor Stuart Phillips

In today’s interview I get to speak with dietary protein expert, Professor Stuart Phillips, about the current research recommendations on how much protein we all need to eat per day to avoid muscle loss as we get older, busting myths that protein damages your kidneys, keto diet mistakes with protein and more.

Stuart is very passionate about muscle health and the understanding benefits of protein in our diets.

He is a Professor in Kinesiology, also an Adjunct Professor in the School of Medicine at McMaster University.

In the interview you’ll hear how important protein as one of the three macronutrients in our diets. He explains how to work out how much protein you need to eat at a minimum in order to stay healthy as you get older.

Prof. Phillips shares some great information about how to calculate your personal protein requirement, difference between animal protein vs plant based protein, and explaining why we all need to eat enough protein to help avoid severe sarcopenia.

We not only talk about why eating protein is so vital, but also dispelling common myths that people might say about eating “too much” protein.

If you know someone who is interested in how to maintain healthy muscle or might be worried if they are not eating enough protein then this episode is definitely for them!

I enjoyed this interview as I know that when I did my first low carb high fat experiment and lost so much weight that unfortunately I would have lost muscle too as I didn’t eat enough protein most likely. After speaking with Prof Phillips I know I need to value eating protein not only to help weight management, but more importantly to help maintain lean muscle mass as I get older.

Special thanks to Stuart for joining me on the show. Enjoy the episode!

Go to Prof. Stuart Phillips official webpage here to find out more about him or follow him on Twitter or Facebook.

Show Notes with Timestamp Links

Highlights of what we talk about during the interview:

Click on one of the timestamp links in the brackets to jump to that point in the interview audio.

[0:20] – Introducing Professor Stuart Phillips, a Tier 1 Canada Research Chair in Skeletal Muscle Health at McMaster University. He is a Professor in Kinesiology, an Adjunct Professor in the School of Medicine and a fellow of both the American College of Sports Medicine (ACSM) and the American College of Nutrition (CAN).

[1:10] – Dietary protein explained. There are 20 amino acids that make up dietary protein, nine of these are essential for us to get through diet as we can’t make these ourselves. Because all the tissues in our body are broken down and regenerated on a daily basis – this is called protein turn over – protein is one of the only macro nutrients that we have a daily need for. Professor Phillips gives us a great analogy to explain this process. The other two macronutrients are fats (which we also need to eat) and carbohydrates (which we can get away with not having).

[2:55] – What is sarcopenia? Irwin Rosenberg, coined this medical term which means a gradual, age related decline in muscle mass. It is taken from Greek word ‘sarx’ or flesh & ‘penia’ or loss. Sarcopenia starts somewhere at the age 40- 50 (especially in more sedentary individuals) & occurs in everybody at a rate of 0.5-1.5% per year. This decline doesn’t become noticeable until certain tasks such as getting out of a chair become difficult later in life. (ref & ref)

[4:35] – Can the rate of sarcopenia be slowed with the intake of enough dietary protein? Other than the hormonal changes that people experience with age the two main drivers in keeping the muscle mass constant are physical activity and dietary protein.There are examples of individuals who remain extremely active in later life that maintain the body composition of someone in their 30’s or 40’s. Inevitably though even they will begin to lose some of that muscle mass. For people who don’t do any physical activity the muscle mass is lost at a faster rate and this can be mitigated somewhat by diet.

[4:35] – Gary previously talked to Dr Agnieszka ‘Aga’ Burzynska who studies Masters athletes and saw the benefits of taking up exercise for people later in life. Professor Phillips agrees exercise is important, in fact all of the studies at the Department of Kinesiology at McMaster are done against a backdrop of some type of exercise. For maximum benefit, the take away is: eat enough protein and do some exercise. (Biohackers Lab Tip: check out our review of using a whole body vibration exercise machines)

[7:04] – Discussing the concept of banking muscle when we are younger; while it does make sense to exercise when we are young, the definition of what it means to be ‘old’ is changing as life-expectancy is increasing, so these muscle stores may not be enough. We need to keep the ‘bank’ open and keep exercising well into our 30’s and 40’s and beyond. It is good to keep in mind that physical activity comes in many shapes and forms, whatever will get people of the couch is encouraged.

[9:14] – Prof Phillip explains why he believes the Recommended Daily Allowance (RDA) of protein is currently too low. RDA suggests that this is all you are allowed to have and the traditional methodology, using nitrogen balance technology, to establish this number is very old and flawed. There are disagreements on what method should be used to replace the currently used methodology, but strides have been made. In the interim, observational findings indicate that older people who eat more protein tend to do better, particularly in preservation of muscle.

[11:48] – Vitamin C was once treated in the same way as protein and now we know there are other benefits to a higher intake of Vitamin C, other than just having the minimal amount necessary for preventing scurvy. Similarly, protein has other benefits with increased intake. Professor Phillip believes that RDA should be called MDA (minimum daily allowance) as it defines the minimum value needed to offset a deficiency but doesn’t set the optimal value.

[13:37] – Clarifying what the RDA numbers mean; current amount is set to 0.8 g of protein per kg of body weight. To illustrate, a woman of 50kg (130 pounds) should be consuming 40 g of protein, this could be a 500ml (two cups) serving of milk – which contains 18 g of protein – plus a moderate serving of chicken. We can see from this example that we don’t have to consume a lot of protein to hit the target. Professor Phillips explains that the body can use the extra protein to a certain extent.

[16:06] – 100 grams of meat is not 100 grams of protein. Depending on the type of meat, there is water content and fat content to consider also. On average, a 100 gram steak would equate to about 30-40g of protein.

[17:42] – What are the requirements like for children? Because kids are growing, they have greater requirements and this will vary according to the stage of development they are in. Infants need 2g/kg of body weight. Professor Phillips explains that for the most part, recommendations that are set for kids are probably appropriate, as they have been informed by studies where children in food insecure regions had food re-introduced into their diets and their linear growth was recorded. The problem is with the elderly population, where Professor Phillips believes the RDA is greatly underestimating how much protein is needed; it should be upped by at least 50% to 1.2 g/kg/day or even by 100% to 1.6 g /kg/day.

[19:18] – How is this requirement different for diabetics? Insulin most likely plays a role in protein synthesis; Professor Phillips explains that from what we know, type-2-diabetics are probably far less efficient at turning protein from their diet into muscular protein than healthy individuals of the same age. Exercise, particularly resistant exercise, however, does stimulate these processes and makes you anabolic. With type-2-diabetics there is also kidney disease/renal disease to consider. Professor Phillips stresses that he is not a clinician and refrains from giving any medical advice but says that stabilising blood sugar and managing insulin would mean that protein requirements for minimising muscle loss would probably be about the same as for the average person.

[21:49] – A colleague Professor Phillips used to work with, Professor Mike Rennie, called this effect anabolic resistance; when the muscle becomes resistant to anabolic stimuli. The elderly and people with type-2-diabetes are less efficient in how they use their protein to make new muscle. For the elderly, it may help to make more protein available by having more protein in their diet. (ref + ref)

[22:48] – Keto Nutritionist Emily Maguire, found that one of the biggest problems she deals with is that women on ketogenic diets tend to under-eat protein. The keto/low carb diet has grown in popularity for a variety of reasons, ranging from people wanting to lose weight and manage their insulin to managing epilepsy. Are people who are looking to lose weight on this diet eating enough protein? Professor Phillips explains why not getting enough could be a problem; one of the hormones that is markedly anti-proteolytic (proteolysis is the process of the breakdown of proteins) is insulin, which is low in ketogenic individuals so there is nothing putting on the brakes on the breakdown of proteins. We also learn that in addition to eating enough protein, generating muscle is dependent on activity. The less active we are the less of those amino acids go into muscle. Professor Phillips illustrates this point by reminding us what happens when we take off a cast off a broken leg/arm. As we get older there is a contribution of inactivity and under-consumption of protein.

[25:55] – People who practice the ketogenic diet limit their protein intake as it results in a raise in insulin. In terms of weight loss, if you are older and 30-40% of your weight loss is muscle that is not good. High quality weight loss means as high a percentage as possible weight loss is fat.There are two ways to achieve this: one is through exercise, in particular anabolic type such as weight lifting and second is increasing protein intake. Asking older people to lose weight can be controversial as you are accelerating sarcopenia. What’s worse the weight people tend to gain back is not muscle!

[28:50] – Talking about the Biggest Loser TV show, the winner always loses the most muscle as it weighs more than fat. Muscle also burns more energy – Professor Phillips explains that what makes up the resting metabolic rate really comes down to two things, the liver and muscle.

[30:27] – Eating butter and cheese is not high enough in protein. As we get older meat may be more difficult to chew but finding good protein sources is important;1egg is 5g of protein which means you’d have to eat a lot of eggs!

[32:07] – Gluconeogenesis is a concept that comes up a lot; it is a problem when going keto and eating too much protein. Rather than thinking about how much protein we can digest – which is quite a lot – we need to think about how much we can use? After we expel Nitrogen, which is toxic, through urea, we are left with the carbon skeleton which is exceptionally difficult to turn into fat.But even though it is available to make blood glucose, Professor Phillips explains the amount produced from gluconeogenesis will not mess with your insulin. It is true that protein itself is insulinogenic but he believes that the body can withstand fluctuations within a certain range of insulin and not get out of ketosis. It is possible to consume 1.2 and up to 1.6 g of protein and still maintain ketosis.

[36:34] – Thoughts on carnivore diet/zero carb diet where someone eats 2kg+ (4-5pounds) meat a day like Dr Shawn Baker, whose athletic performance has gone up on this type of diet. This is definitely an extreme diet, but Professor Phillips believes that as long as you are getting all the essential fats and enough protein you can survive on zero carbs. He also believes that people on this diet would have pretty high ketone bodies.

[38:35] – Diet and food are very personal. Professor Phillips explains how when drugs are tested the average response is taken and often, along with the people who respond well to a drug, there will also be people who get no effect at all. Diets work in the same way, certain diets work for certain people. People are adaptable and you can find individuals on each side of the scale – from plant only to diets that are high in meat – who are doing very well without any adverse effects. There is no single right way. It is only with the addition of modern food additives – a big one being sugar – that we begin to see problems.

[41:44] – Vegetable protein vs. animal protein. We talked about the nine essential amino acids earlier, can we get these from vegetables alone? Proteins are graded on a quality scale which includes a measure of digestibility and the content of essential amino acids. Plant proteins have lower essential amino acids concentrations and contain dietary fibre which adversely affects digestibility. So, it would be fair to say that, in general, animal source proteins have higher protein quality and are nutrient rich sources of dietary protein; many of these nutrients such as iron, zinc, B12, calcium and potassium are shortfall in older people. To get the same from plants we have to be more thoughtful about planning our diet. For e.g., an interesting observation is that in areas where there is a scarce supply of meat and dairy people consume more beans, rice, legumes etc which are sufficient in supplying the essential amino acids.

[44:47] – Myth 1: Too much protein creates kidney damage! That is just not correct. This belief comes from renal wards where people suffering renal and kidney disease are all told to consume lower protein diets because this results in generation of less urea. These people when put on a lower protein diet in turn do live longer. What this does not translate to is protein causing the kidney disease in healthy individuals in the first place; caution is needed, however, for people with type-2-diabetes. Both the WHO as well as the Institute of Medicine have given statements that say that there is no relationship between dietary protein and the decline in glomerular filtration rate. In six months or so Professor Philips also hopes to share the results of a meta-analysis that will show that the low/high protein diet has no long-term impact on renal function. (ref + ref)

[48:43] – Explaining why data on bodybuilders does not necessarily provide a fair representation of the effects of high protein diets. Bodybuilders tend to experiment with other substances that may be shortening their lives. We should not be looking to them and assuming eating a lot of protein is what’s causing the damage to detoxing organs such as kidneys or the liver.

[49:44] – Myth 2: Too much protein results in acidosis, resulting in dissolving of the bones! There was a study that came out of Harvard, led by Professor Walter Willett, where it was observed that people with higher protein diets had a higher calcium content in their urine. Professor Phillips explains the acid-ash hypothesis that resulted from this observation and explains that the calcium that comes out in the urine on a higher protein body is not from your bones –your body actually absorbs more calcium so you get rid of more calcium. It is interesting to note that 50% of the bone is made up of collagen protein, with adequate calcium and vitamin D intake protein is bone supportive. This was supported by the meta-analysis sponsored by the National Osteoporosis Foundation.

[52:38] – Professor Phillips says he is yet to see good evidence that taking collagen supplements helps. However, he mentions a colleague, Professor Keith Baar, who believes that if you take gelatine and a high dose of Vitamin C before exercise that it helps to regenerate active tissues, like tendons, and says that while he does not think this is a bad thing to do, he stands to be convinced that it is true. (Biohackers Lab Tip: check out our Bulletproof collagen vs collagelatin review)

[53:23] – Collagen is very low in essential amino acids, but has amino acids that are present in collagen. Someone on a high protein diet would be getting all the amino acids they need to make adequate amounts of collagen. There is some evidence that suggests that there may be something to the collagen theory, but at this stage Professor Phillips remains unconvinced.

[54:53] – Gary hopes to get Professor Phillips on the show again to talk about what he found out about high intensity vs. low intensity resistance exercise. It is something that generated the largest amount of hate mail for him!

[55:24] – Professor Phillips reiterates that the articles stating that we are getting enough protein are using a yardstick short of where it should be. We are getting minimal rather than optimal amounts of protein and he hopes to produce some of the evidence needed to change people’s minds with regards to this in the years to come.

[56:16] – Lastly, how does fasting affect protein? With people practicing prolonged fasting of upwards of 18 hours, their fat is being broken down for fuel but we also see a breakdown of a little muscle protein. Professor Phillips believes that if you are getting some sort of resistance exercise the loss of muscle protein will be minimal; with age, the amount of muscle protein lost will probably increase a little, but a higher protein diet can help mitigate this loss. (Biohackers Lab Tip: check out our review of the best grass fed whey proteins here.)

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6 thoughts on “How Much Protein Should You Have a Day? (+ Keto Protein Mistakes) • Prof Stuart Phillips”

  1. Excellent podcast Gary. Thank you for such high quality content. Will you please clarify a few questions for me?

    Did Stuart recommend a maximum limit to protein input?
    Say for instance the following scenario.
    A 56 year old, healthy and fit, 70 kilo male, is on a ketogenic diet, works in light construction and runs 5 miles three times per week. Would his protein intake be 1.60 max?

    Is there a good and cheap way to accurately measure how much protein a person needs?

    If a person is on a ketogenic diet should he/she consume more protein due to the fact that he stated that insulin helps retain protein and a keto diet is by default low in insulin?

    Thank you so much for helping me out with these questions. May you have an awesome life filled with peace, joy and good health.



    • Hi AR,

      Thanks for the questions. Prof Phillips gave me some answers for you, he was typing on an iPad:
      1. Did Stuart recommend a maximum limit to protein input?
      [SP] You can eat a LOT of protein. What I said was that up to 1.6 g/kg/d you can still see benefits to muscle, beyond that it’s not possible, but folks can east up to 3-6 g/kg/d (a lot of protein)

      Say for instance the following scenario.
      A 56 year old, healthy and fit, 70 kilo male, is on a ketogenic diet, works in light construction and runs 5 miles three times per week. Would his protein intake be 1.60 max?
      [SP] I would say yes, but he could certainly eat 3.2, just no benefit to muscle.

      2. Is there a good and cheap way to accurately measure how much protein a person needs?
      [SP] I’m not sure I understand? Beyond the recommendation of 1.6 g/kg? In short, there’s no good and cheap way to measure a person’s requirement for any nutrient a person needs unless they’re part of a study.

      3. If a person is on a ketogenic diet should he/she consume more protein due to the fact that he stated that insulin helps retain protein and a keto diet is by default low in insulin?
      [SP] I think so… protein will not raise insulin so high that ketosis will be interfered with. I actually think a low protein keto diet is a recipe for muscle loss in an inactive person especially if they’re older: low protein (less than they need) and low insulin, which inhibits protein breakdown. Not a good combo. There are of course higher protein keto advocates and IMO they’d got it right. I know people say the ketones ‘spare’ muscle, but there’s no science behind that.

  2. I missed where he says how much protein should we have? Didn’t hear any specific numbers, sorry if I missed it somehow!

    All the best,

  3. Are the mentioned protein grams per kilogram recommendations based on a person’s current weight, ideal weight, or lean body mass? Those numbers can differ greatly for obese people!

  4. I have a condition – a relatively minor stutter that becomes apparent when having to read aloud such as during site meetings.

    I would like to experiment by eating healthily on a ketogenic diet to see whether reducing glucose completely for example, will ‘repair’ the speech function of the brain through the effects of autophagy.

    Would there be any study on the effectiveness of this as a form of treatment?

    You might have experienced this?

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