nutritionista:

I always talk about how crucial protein is to any diet, especially if you’re trying to lose weight. But I’m sure it gets confusing. How much are you supposed to eat in a day and from what sources? Reader Leslie asks:

I wonder how much I protein I should really be getting in a day? I know that it is not good to source all protein from shakes and that too much protein and not enough water leads to kidney stones. As a 24 year old, 5’ 9”, 145lb female, how much is the right amount?

How much of this stuff do I need?

According to this article from MSNBC (and also from what I’ve heard/recommend), between 10 and 15 percent of your total calories should come from protein. Another way to calculate it is that you should try to eat around 0.4 grams of protein per day per pound you weigh. That means as a 145-pound person, Leslie should shoot for around 58 grams of protein per day.

Most people don’t need to worry about getting too much protein. Unless you have liver or kidney disease, it’d be pretty difficult to overdo it.

Animal, vegetable, or mineral? (For those of you who don’t like wordy explanations, this is the part you should skip.)

Protein consists of amino acids, of which there are around 20. Essential amino acids are those that your body can’t produce on its own, whereas non-essential amino acids can be made from essential aminos. Your body needs all 20 amino acids, and the real difference between animal and vegetable protein is that animal protein is “complete” while vegetable protein is “incomplete.” If it a protein is “incomplete,” it means that it’s missing crucial amino acids. Vegetarians must get their protein from a variety of sources to get all the necessary amino acids (legumes, nuts, grains, soy, etc.). Fun fact: eggs are considered the most ideal protein in terms of “usability” by the body. Mmm, eggs.

Bottom line

For everyone, vegetarian or not, it’s important to get protein from a VARIETY of sources. I usually get about 75 percent of my protein from vegetarian sources and maybe 25 percent from animal sources. I also think a 50/50 ratio of animal to veggie protein would be good. Whatever you do, choose lean protein to avoid getting lots of extra fat along with your protein source. It’s okay if some of your protein comes from whey or soy shakes, as long as not all of it does.