Further to my post: http://www.irondaughterirondad.com/show-me-the-protein/ …although other elements come into play in going vegan, like B12, iron, and other nutrients, for time and space I’m going to leave that for another day…
so protein…well, there are literally billions of words written about protein and the vegan diet…and tied together is the discussion of amino acids. Protein is made up of long chains of amino acids, and therefore a particular protein is determined by the amino acid ‘ingredient blend’.
I’ve included some links in this post…not so much the most ‘authoritative’ ones that I have, but rather ones that addressed a particular point without being too overwhelming.
…I particularly like this chart where you enter in your ideal weight or actual height, and it calculates the protein and amino acids that you need, and the foods that have them…very nice starting point: http://www.veganhealth.org/articles/protein
Without getting into the minutia of the difference in ‘numbers’ that you’ll see, there are currently 20 or more amino acids, 8-10 (depending on how you classify them) of which are referred to as ‘essential’ since they can’t be manufactured by the body, and therefore need to be consumed in food…and fundamental to your body functioning properly: http://en.wikipedia.org/wiki/Essential_amino_acid
The reason that this is important in a discussion of a vegan diet is that meat and fish protein already contain the percentage balance of amino acids found in human proteins, and are therefore called ‘complete’ or ‘high-quality’…in the vegan diet, soy has the same ‘complete’ amino acid structure, with legumes being close…non-soy plant proteins have a lower percentage of at least one essential amino acid, so in summary: “legumes are lower in the amino acid methionine while most other plants foods are lower in lysine”
- Grains (lacking in lysine): brown rice, rye, wheat, cornmeal, barley, millet, oats, buckwheat
- Nuts and Seeds (lacking in lysine): walnuts, cashews, almonds, pecans, sunflower seeds, pumpkin seeds, sesame seeds, flax seeds, hemp seeds
- Legumes (lacking in methionine): beans, peas, lentils, garbanzos (chickpeas)
…and just to make a note of it, vegetables and fruit are both lousy sources of either lysine or methionine…and protein in general…so you can’t just ‘go vegan’ and be healthy by only eating your veggies and fruit shakes…sometimes ‘leafy greens’ are pointed to as good protein sources…the trick is that they may have a high ‘percentage’ of calories as protein, but since their calorie value is low, it takes a ‘ton’ to get any protein…okay not a ton…but 4 cups of spinach (20 calories) gives you 2 grams of protein…3 ounces of beef tenderloin (200 calories) gives you 23 grams of protein…3 ounces of tuna (100 calories) 20 grams…to be equivalent, you’d need to eat 40 cups…figuratively a ton 🙂 …of spinach to get 20 grams of protein…so that’s not a good primary basis for protein in a vegan diet
In a further point, in a 2009 a joint position paper on nutrition and athletic performance, the American College of Sports Medicine (ACSM), the American Dietetic Association (ADA), and Dietitians of Canada recommend:
“Because plant proteins are less well digested than animal proteins, an increase in intake of approximately 10% protein is advised (Iron Dad note: over the recommendations for non-vegetarian athletes). Therefore, protein recommendations for vegetarian athletes approximate 1.3–1.8 g/kg/day (Iron Dad note: vs 1.2 to 1.4 g/kg/day for non-vegetarian athletes).”
…and the vegan diet tends be lighter in protein (10-12%) than non-vegetarians (14-18%)
So into more detail with the amino acid makeup of protein…in the vegan diet…”soy r us” in terms of ‘complete protein’…and then a wide ‘variety’ of legumes and non-soy plant foods to even out the deficiency that one food may have, that is picked up by another…particularly shortfalls in amino acids, lysine and methionine.
…and although soy is a more rounded protein, there’s quite a bit written ‘cautioning’ about too much soy…a soy-positive slanted article: http://www.veganhealth.org/articles/soymessina, and one slanted the other way: http://www.naturalhealthstrategies.com/dangers-of-soy.html …and one attempting to be balanced, but still leans moderated-soy: http://thyroid.about.com/cs/soyinfo/a/soy.htm …soy ‘isoflavones’ appear to be particularly bad.
…so I’m left thinking that the protein ‘question’ in a vegan diet, although often defensively dismissed by vegan proponents in what I’ve read, is a legitimate thing to be aware of…seems to me that if you don’t ‘watch’ the protein and plan for it, it’s too easy to be short or out of balance…and particularly if you’re also short on overall calories…double jeopardy…the idea here is to eat healthy correct?
So why not just eat meat and fish, get your protein and be done with it?…well the vegan proponents have many reasons…aside from the ethical vegan focus on animal rights…a couple of primary ones:
- …although a ‘complete’ protein, meat in particular can carry with it high levels of saturated fats…so in my experience ‘lean’ meats and fish only, if you want to keep saturated fats at 3-5% (7% the generally regarded red-line)…throw in a rib-eye steak, or hamburger, or ribs, or chicken wings, and watch the numbers explode through the top.
- …and links to cancer, and other bad stuff
Suffice to say with all of it, that it’s an imperfect world when it comes to diet, and that if you do any reading, you can find a scientific study to ‘prove’ anything on any side of an argument.
So what am I left with? …on my vegan diet week, I’m going to work in some soy but limit it, so that’s going to make it more challenging:
If you are going to eat soy, select fermented and food forms of soy, for example tofu, tempeh, and miso. Avoid processed soy products — including soy powders, protein shakes, and other processed forms of soy.
From what I’ve read, it seems to me if I focus on foods that specifically target lysine…for me about 3,000 mg daily…and secondarily methionine…for me about 1,500 mg daily…the rest of the protein equation should fall into place.
…so the early list of foods, that look good to me ( in brackets, 1 serving in mg: L for lysine, M for methionine)…so will need about 6-7 servings to hit the numbers each day…well, throwing in some soy sometimes will help that out…1/2 cup of firm tofu starts me with (582L, 177M) or tempeh (754L, 305M):
- for lysine, non-soy legumes like: black beans (527L, 197M), chick peas (486L, 193M), lentils (624L, 193M), dry roasted peanuts (410L, 286M), peanut butter (290L, 202M)
- for methionine, grains like: quinoa(442L, 295M…double winner), corn (232L, 158M), spaghetti (127L, 292M)…oatmeal (316L, 335M) fits the criteria nicely, but only if desperate
…by comparison…3 ounces of tuna: (1992L, 874M) or 3 ounces of beef tenderloin: (1620L, 500M)…sort of highlights the difference between the amino acid/protein differences in the 2 diets