Is rice and beans a complete protein

What is the rice ratio needed for lentils to be "complete protein"?


I will act in the interests of the OP and will not close the question. I'm assuming that my premise that ratio doesn't matter (explained in the main answer) is an established fact (at least I don't know of any source claiming otherwise). If we find an assertion to the contrary, we have to close the entire question, as it means that even at this very general level there is no undisputed answer and the question falls entirely within the realm of "unverifiable" nutrition.


There is no such ratio because whole proteins are not about ratios. They are about minimal intake of essential amino acids. This means that if you were only eating rice and lentils and nothing else (or at least no other sources of protein), you would only have to eat a minimal amount of rice per day to avoid deficiency symptoms. If that amount of rice is X grams, it doesn't matter whether you are eating X grams of rice and 2X grams of lentils or X grams of rice and 10X grams of lentils. The rice to lentil ratio doesn't matter.

Probably the more interesting question for you is how much rice you need to eat minimally each day. There are freely available nutritional databases such as the one linked to derobert. Once you've established that you want to eat at least Y mg of a certain amino acid per day (supposedly an amino acid not found in lentils), you can use a simple rule of three to calculate how much rice you need to eat, to obtain Y mg of the amino acid in question.

But how do you decide how much to eat? There are government approved RDAs as well as thousands of sources at all levels of credibility recommending their own intake levels, which usually indicates that RDAs are deliberately conservative. We cannot help you with this decision. It is completely inappropriate for us, and it is up to you to find such sources and decide which ones to believe in. Consulting a nutritionist is a very good option if you are on a severely restricted diet. They will likely be able to give you such value. Personally, I would not trust a number given to me by a stranger on the internet and would try to keep in mind that the minimum amount (below which you will get deficiency symptoms) and the optimal amount are most likely not the same, but many sources merge them.

rumtscho ♦

I'm converting this post to a community wiki, not because I think other users need to add to it, but because I have a conflict of interest between my decision not to close the question (which I may still change until a new one is available ), want to visibly prevent information on this topic) and the fact that I answered it and the answer brings positive voices for me.