Originally Posted by
phoebeisis
Plant proteins-not as valuable or as high Biological value as animal proteins-incomplete if you use a single plant based protein-hence beans and rice
peanuts and bread
Hard to beat milk as a food if you are short of money-maybe eggs too
20 cents/egg- 6 grams or so of protein high biological value protein.
Of these protein sources, eggs are really the only one I would consider high quality. You can survive on beans and rice or peanut butter and bread, but thrive? Well, opinions vary.
One of the problems with plant protein sources is that they come bundled with a lot of carbs. Peanuts aren't too bad on the carb side, but bread, which you need to fill out the protein profile, is nearly all carbs. If you're trying to get an 'athletic' dose of protein during the day, you're eating a massive whack of carbs. There's also the issue that only a portion of the carbs you eat from something like peanuts is actually bioavailable. In the case of peanuts, it's on the order of 52%. Wheat is 42%. So if you're looking at a peanut butter sandwich that has 15g of protein, your body is only going to be able to extract maybe 7-8g of protein out of it. For reference, a whole egg is 100% and beef is 92% bioavailable. These things are not all created equal.
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