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My course notes

My course notes make the following points about protein:

• Functions of protein: the following are key roles of protein:
  • To make enzymes
  • To make hormones (e.g. insulin)
  • To make antibodies
  • To make muscle fibres and other body tissues
• Structure of proteins: proteins are made up of amino acids, which can be divided into 12 non-essential (secondary) amino acids and 8 essential (primary) amino acids.  The human body can manufacture the non-essential amino acids but must obtain the essential ones from its diet.
• Protein requirements: dietary protein is used to provide amino acids to cells for protein synthesis.  Protein is the only macronutrient to contain nitrogen, which is used in DNA.  There is a fine balance between protein utilisation and breakdown and the broken down elements of protein end up in urine as nitrogen containing compounds.  Nitrogeneous waste in the urine is therefore a way of monitoring whether the balance is positive or negative.  This is called nitrogen balance and is how researchers identify how much protein is needed by the body.
• Daily recommendations: the following RDA amounts are recommended:
  • For a sedentary person is 0.8g per kg of bodyweight per day (est. 10 – 15% of total calories)
  • For an endurance athlete is 1.2-1.4g per kg of bodyweight per day
  • For a strength athlete is 1.4-1.8g per kg of bodyweight per day
• Health risks of a low protein diet: include the following:
  • Inadequate repair and growth of body tissues
  • Inadequate enzyme production
  • Inadequate hormone production
  • Inadequate antibody production
• Health risks of a high protein diet: include the following:
  • Can lead to kidney damage in individuals with existing kidney problems
  • Ammonia accumulation in the blood
  • Storage of excess protein as fat

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The key questions

I figure that the key questions when it comes to protein are:

• How much protein do people need to achieve their health and fitness goals?
• How much protein is unhealthy?

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How much protein do people need?

Well, everyone has an opinion about this, it’s true.

My course notes identify protein requirements between 0.8g and 1.8g per kg of bodyweight, depending on activity levels.  So for someone of a bodyweight of 75kg, this would amount to between 60g and 135g.  Assuming that a sedentary person weighing 75kg would be eating around 2,000kcal, this would be 240kcal from protein, or approximately 12% of calories.

The Food and Drug Administration (FDA) in the US recommends 50g for someone eating 2,000kcal per day.  This is 200kcal from protein, or 10% of total calories.  (And just for the record, 50g of protein is basically a single chicken breast.  Just so you know how ridiculous that recommendation is).

So what do strength athletes and bodybuilders think about these suggestions?  Well, Dr Clay Hyght notes in his article on high performance nutrition that between 1.5g and 2g of protein per pound of bodyweight (3.3g – 4.4g per kg) is generally regarded as the level required for serious trainees.  Assuming our hard-training 75kg person is eating 3,000kcal, this would be 990 – 1,320kcal or between 33 – 44% of total calories.

And Chris Lockwood, a nutrition researcher, wrote a fantastic article on T-Nation about his research into protein requirements.  He concluded that for trainees who are engaged in serious levels of activity, an RDA of 1.36g of protein per pound of bodyweight (2.92g per kg) is appropriate.  So, again, for our hard-training 75kg person eating 3,000kcal, this would be 876kcal or 29% of total calories.

Quite a difference…

And what macronutrient ratio appears in the Paleo Diet?  After all, if you were looking to keep an animal healthy in captivity, wouldn’t you assess it’s diet in the wild first?  The Paleo Diet has a library of research and a paper on that site (Estimated macronutrient and fatty acid intakes from an East African Paleo Diet) suggests that an East African hunter-gatherer diet has a ratio of 25% protein, 35% fat and 40% carbohydrate.  That would be 500kcal or 125g in a 2,000kcal diet.

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How much protein is unhealthy

My course notes identify that “excess protein” can:

• Lead to kidney damage in individuals with existing kidney problems - you might expect that this claim would irritate the life out of me but I was actually quite pleased by the admission that it is only people with existing problems can get kidney problems.  About ten years ago, all of the manuals were claiming that high protein diets caused problems for healthy people.  You can read the American Heart Association reported on the BBC talking about this in 2001.  So this is genuine progress!  And, as John Berardi notes, if you don’t like protein for its acid load then you shouldn’t be recommended grain-based diets, should you?
• Cause ammonia accumulation in the blood – however, the establishment just can’t get their heads around the idea that protein might be safe so they come up with something else.  Dr Lonnie Lowery, another nutrition scientist and powerlifter, explains why he thinks this is.  Lowery says: “I just wrote a scientific review (Dietary protein and resistance exercise: what do we really know?) about the huge disconnect that exists between academic textbooks and the actual published scientific literature when it comes to protein and athletes. This is the first time anyone has ever objectively looked at the anti-protein messages out there in some textbooks and certain personal-training manuals.  I was absolutely shocked at some of the language that’s been used: protein is hard on the kidneys, it weakens bones, it’s high in saturated fat.  But when you actually sit down and look at the literature, there is very little support for any of those dramatic claims.”
• Be stored as fat – this is so stupid, I don’t even feel the need to respond.

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Now, if you excuse me, I’m going to go eat some more protein…

The original and best work

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Before you start: remind me, what is the Paleo Diet again?

*Sighs* The Paleo Diet is based on the principle that less than 10,000 years ago (and for the 2.5m years before that), every single human(-oid) on the planet ate the same diet.  The diet is basically what we ate before the development of agriculture, which is what we could hunt or gather.

This meant that we ate mainly lean meat, fruits and vegetables.

And by inspecting their bony remains, scientists observed that these stone-age humans were almost entirely free from obesity, heart disease, tooth decay and many other ailments that best modern people.  They therefore concluded that the diet could be the secret to health and longevity.  Consequently, they hypothesised that we actually evolved to absorb these foods better and more efficiently than any other foods.  It makes for a compelling thesis.

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And why is this diet so radical if everyone used to eat it?

Well, notably absent from the list of foods eaten by ancient humans is the foundation of the modern food pyramid, all 6-11 servings of it:

The Food Pyramid: adopted by the US Department of Agriculture in 1992

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This means that the Paleo Diet flies in the face of modern nutritional wisdom.  If you’re interested in reading more about food groups according to the US Government, you can read about their selection of research papers on macronutrients here and you can read their recommendations here.

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OK, I’m with you now.  Hit me.

My pleasure.  The Paleo Diet is the fundamental work on the diet of our ancient ancestors and the diet that our bodies are designed to eat.  It’s set out in three main sections but it’s really not that strongly subdivided (which really bothers me as an anally-retentive, analytical type).  I guess in order to appeal to a wider, less boring audience, it’s been written as more of a chatty sort of book that covers the material in a loose structure.

At it’s most basic, the Paleo Diet has six rules, which are laid out in chapter two:

1. All the lean meats, fish and seafood you can eat
2. All the fruits and vegetables you can eat
3. No cereals
4. No legumes
5. No diary products
6. No processed foods

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Yeah, I’ve heard all that before.  What’s new?

Well, you’re right.  Not much is new.  In fact, it’s about 2.5m years old.  You can summarise the Paleo Diet down to a very simple formula.  I mean, how complicated can it be if a caveman can understand it?

And, yes, having read the book from cover to cover, I think that 90% of the book is explained just by those six rules.  So if you’re the laid-back type and you’re happy you’ve understood those rules then read no more.

However, Cordain makes a number of fundamental points that differentiate him from popular mainstream writers such as Mark’s Daily Apple (and I use Mark’s Daily Apple as an example simply because his site is great and it’s easy to navigate and find things).

Check out these examples:

• The Paleo Diet isn’t the same as a low-carb, high-fat diet.  Cheese, butter and bacon are not staples of the Paleo Diet (c.f. Mark’s Daily Apple on saturated fat)
• Saturated fat is bad for you and causes high cholesterol (c.f. Mark’s Daily Apple on cholesterol)
• Hunter-gatherer diets were rich in fruits and vegetables (but not starchy potatoes) and The Paleo Diet not therefore a low-carb diet (c.f. Mark’s Daily Apple on low-carb diets)
• Stone-age humans ate very little salt (c.f. Mark’s Daily Apple on salt, which is similar but less militant)
• The Paleo Diet is based on lean meat (55% of total calories), which increases the metabolism and reduces the risk of heart disease (c.f Mark’s Daily Apple, which assumes 1g of protein per lb bodyweight (maybe 25% of total calories)

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What else is interesting?

Well, if you enjoy getting under the skin of our ancient ancestral diets and the whys and the wherefores, Cordain goes into some of the scientific theories that have been constructed around the development of the human body in conjunction with its diet:

• Lean meat is the reason that humans developed larger brains
• Grains are what cause health problems: the fossil record shows that the early farmers were plagued with vitamin and mineral deficiences and they are the first to show tooth decay
• Farming cultures lack Vitamin C because cereals have zero Vitamin C
• Cereals are also poor sources of the B vitamins, despite what cereal packets will claim (I’ve always thought cereals had to be bad for you.  I mean, why would they have to add so many extra vitamins to it if it were naturally good for you?)
• Syndrome X diseases (type 2 diabetes, heart disease, hypertension, obesity, myopia, acne and breast, prostate and colon cancers) are linked to elevated levels of insulin in the bloodstream

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Why should I read it again?

This is the fundamental work on the diet of our ancestors.  If you accept the theory that our bodies are designed to run on paleolithic foods, just like a petrol engine is designed to run on petrol and a diesel engine is designed to run on diesel, then you will want to read it.

There are enough differences between this book and the mainstream advice on healthy eating to make you sit up and think.

I make the protein shakes up myself as 30g of Natures Best chocolate whey protein, 30g Myprotein egg yolk powder and 10g Myprotein cold milled flax seed.  Together, each shake gives me 370 calories, with 35g of protein, 23g of fat and about 6g of carbohydrate (most of which is fibre).

Building them into my diet means that when I want to cut weight, I can just lose the two shakes and I don’t really change the amount of solid food I’m putting into my stomach.  Therefore, I don’t really feel any less full.  But the effect of removing them is 740 calories per day.

So my meal plan looks something like this…

Breakfast

• 5 eggs
• 50g broccoli
• 413 calories, 33g protein, 28g fat and 6g carbohydrate (most of which is fibre)
• +4 fish oil soft gels (2,800mg DHA/EPA), 500mg glucosamine

Lunch

• 2 eggs
• 50g hard cheese
• 100g sliced meat
• 1 stalk celery (chopped)
• 1/5 cucumber (chopped)
• 563 calories, 45g protein, 39g fat and 7g carbohydrate (most of which is fibre)

Afternoon snack

• ½ tin tuna
• 1 cup raw cabbage
• 1 tablespoon full-fat mayonnaise
• 312 calories, 44g protein, 12g fat and 3g carbohydrate (most of which is fibre)

Pre-and-post workout snacks (only on workout days)

• 2 apples
• 1 orange
• 250g cottage cheese
• teaspoon of black treacle
• 420 calories, 34g protein, 7g fat and 50g carbohydrate

Dinner

• 125g beef mince (chilli, curry or Bolognese) with onion and pepper
• 50g broccoli
• 470 calories, 37g protein, 25g fat and 17g carbohydrate (most of which is fibre)
• +4 fish oil soft gels (2,800mg DHA/EPA), 500mg glucosamine

Summary

So that works out as 2,430 calories on a workout day with 234g of protein, 121g of fat and 82g of carbohydrate (including 72 calories for the fish oil).  On a non-workout day, it comes to about 1,830 calories with 158g of protein, 113g of fat and 33g of carbohydrate.

It could be better but it could also be a lot worse.  Brian St. Pierre has done a great article recently on his diet and he puts me to shame.  I suppose that’s what happens when you get a nutrition degree, though… Anyway, if money were no object, then I would probably eat a lot more different kinds of fruit and vegetables and improve the quality of my protein sources. 

For example, I would almost certainly: 

• have a mixed vegetable omelette rather than plain eggs and broccoli for breakfast;
• load up on blueberries, blackberries and other fruits high in anti-oxidants for my pre-and-post workout snacks;
• cook up organic lamb chops instead of sliced meat at lunchtime;
• prepare smoked salmon and vegetables for my mid-afternoon snack; and
• take more supplements.