|Chickpeas - protein of awesome|
If you have food limitations that include grains, beans, nuts, eggs, dairy, or soy, this can affect your protein intake, especially if you don't have a wide variety of meats you can eat.
To figure out what your protein needs are, the following chart from the USDA might be useful if you don't have a nutritionist or doctor helping you: 2010 USDA table on macronutrient needs.
For an adult female my age, for example, I'm supposed to be having 46 grams of protein daily according to the USDA. The kids are supposed to have around 34 grams daily.
Finding sources of protein when it comes to animal sources is easy enough to do, and easy to calculate: how much protein your meat had was how much protein you ate. Easy math, yeah?
Finding detailed information on non-animal protein is tougher, because of what is called the limiting amino acid.
Foods like beans and nuts DO actually have all the amino acids that our bodies don't make ourselves, just like meat does. However, they have what is called a limiting amino acid, or an amino acid that is present in smaller amounts than we require it. The limiting amino acids differ by food, which is why vegetarian sources of protein are so frequently paired up with another.
Beans and grains, for example, typically have complementary limiting amino acids, so they give us ALL amino acids in the amounts we need when eaten together. Seeds and nuts have limiting amino acids more similar to grains, so they should be paired with beans as well rather than with grains.
The below link has a great chart (their protein chart, linked to near the bottom of the article) with details on specific limiting amino acids for specific foods.
An important question popped up re: this. How do you add up incomplete protein when you are calculating your protein intake?
I wasn't entirely sure. It didn't make sense to me to add up incomplete protein like complete protein, because it's not complete protein. How do you figure out whether you are getting enough complementary limiting amino acids? How does that work, exactly?
After failing to find a good answer the web, I finally asked my nutritionist about this. According to her, when figuring out your total protein intake, you add up the grams of whole protein plus the grams of incomplete protein and that's considered your protein total. There's no extra fiddling to account for incomplete vs. complete protein. They try to keep it simple
However, you also have to keep in mind what incomplete proteins you are eating, which is where we can run into problems if we're grain free. The assumption seems to be that you will naturally eat incomplete proteins that complement each other to create a complete protein. That might be a good assumption for a person on a regular diet, but with a restricted diet this may be something you need to be paying more attention to. So while you are adding up your protein with simpler math, just remember to eat legumes along with either grains, nuts, or seeds, and that peanuts count as legumes nutritionally, not nuts. ;-)