Essential Amino Acid Profiles for All Common Beans

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Beans are an awesome source of nutrition whether you’re vegan or not.

But…they aren’t perfect. You shouldn’t rely on them for all your protein needs, because as we’ll see, beans are deficient in certain types of amino acids.

Using detailed data from the USDA’s food database, I extracted the amount of each essential amino acid in the most common beans.

First, we’ll look at them altogether to spot some trends, then break down each bean one at a time.

The Number of Servings Required to Meet Your RDA

This section alone will probably contain the answers you were most looking for when you stumbled across this post.

The RDA for all amino acids is in terms of mg per kg of bodyweight. So it’s different for everyone.

By using a 70 kg (154 lb) person as an example, I calculated the number of servings for each type of bean to meet the RDA of each essential amino acid. All servings are 1 cup of cooked beans.

Click the image below to open up the full-size version if it’s hard to see:

beans amino acids servings per day

I applied some basic conditional formatting to the results where green means that it requires few servings, red requires many servings.

The biggest trends that we see are:

  1. All beans are great plant sources of tryptophan, threonine, and histidine.
  2. All beans have low amounts of methionine. It’s one of the hardest essential amino acids to get as a vegan.
  3. Many beans (but not all) have low amounts of leucine and valine.
  4. Fava beans have a low amount of protein overall, and a low amount of all amino acids.

So what now?

Regardless of which beans you eat often, you need to find a better source of methionine.

I’ve compiled the top 30 vegan sources of methionine in another post.

But leucine and valine depend heavily on which types of beans you eat. You should be able to see from the image if the beans you eat are low in those two and whether or need alternative sources.

If you do, here are:

If you can’t tell from the image alone, scroll down to each bean’s individual section below that you’re concerned about.

Soybean Amino Acid Profile

I’ll start with soybeans, as soy products are the most popular. While products like tofu and tempeh might not have the exact same amino acid profile, it should be similar.

Here’s the amino acid profile of soybeans:

 RDARDASoybeans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280270
Threonine (mg)151050886
Isoleucine (mg)201400977
Leucine (mg)3927301589
Lysine (mg)3021001330
Methionine (mg)151050270
Phenylalanine (mg)2517501006
Valine (mg)261820988
Histidine (mg)10700598

For almost all amino acids, it takes only 1-2 servings of 1 cup of soybeans to reach the RDA for a 70 kg person, which is great.

The only weak point, as with every other type of bean, is methionine. It takes about 4 servings of soybeans to hit the RDA for methionine, which is quite a lot.

Overall, soybeans have one of the best bean amino acid profiles.

Kidney Bean Amino Acid Profile

My personal favorite bean to pair with rice, let’s take a look at the amino acid profile of kidney beans.

 RDARDAKidney Beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280182
Threonine (mg)151050646
Isoleucine (mg)201400678
Leucine (mg)3927301227
Lysine (mg)3021001053
Methionine (mg)151050230
Phenylalanine (mg)251750830
Valine (mg)261820804
Histidine (mg)10700428

Again, weak in methionine (needs about 4 servings to hit RDA), but all other amino acid RDAs can be met with about 2 servings of kidney beans.

The only exception is that it takes ~2.5 servings to hit the valine RDA.

Black Bean Amino Acid Profile

Black beans are a very common type of legume to include in vegan recipes.

Let’s look at their profile:

 RDARDABlack beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280181
Threonine (mg)151050642
Isoleucine (mg)201400673
Leucine (mg)3927301218
Lysine (mg)3021001046
Methionine (mg)151050229
Phenylalanine (mg)251750824
Valine (mg)261820798
Histidine (mg)10700425

Black beans have a very similar amino acid profile to kidney beans. Most amino acid RDAs are met within 2 servings, but valine needs a little more (again about 2.5 servings).

As with all beans, there is a low amount of methionine.

Navy Bean Amino Acid Profile

Navy beans are frequently used in BBQ bean recipes.

Here’s what the profile looks like:

 RDARDANavy Beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280182
Threonine (mg)151050526
Isoleucine (mg)201400704
Leucine (mg)3927301274
Lysine (mg)302100946
Methionine (mg)151050202
Phenylalanine (mg)251750857
Valine (mg)261820917
Histidine (mg)10700375

Navy beans have arguably the most balanced amino acid profile of all the beans. It takes right around 2 servings to meet all RDAs with the typical exception of methionine.

Adzuki Bean Amino Acid Profile

Adzuki beans have the second highest protein content per serving of all the beans here, and one of the best profiles as well:

 RDARDAAdzuki Beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280166
Threonine (mg)151050587
Isoleucine (mg)201400690
Leucine (mg)3927301454
Lysine (mg)3021001304
Methionine (mg)151050182
Phenylalanine (mg)251750915
Valine (mg)261820890
Histidine (mg)10700455

Even the harder to get amino acids, like valine and leucine, are found in decent amounts (takes about 2 servings to reach the RDA).

But the methionine content is lower than the other beans we’ve looked at so far. That shouldn’t be a big deal because you should be getting methionine from other sources.

Mung Bean Amino Acid Profile

Here’s the amino acid profile for mung beans.

 RDARDAMung Beans
 mg per kgfor 70 kg person1 cup
Threonine (mg)151050465
Isoleucine (mg)201400600
Leucine (mg)3927301099
Lysine (mg)302100990
Methionine (mg)151050170
Phenylalanine (mg)251750858
Valine (mg)261820735
Histidine (mg)10700414

It’s a little low in leucine and valine than the more popular beans, requiring almost 3 servings to meet the RDA.

It’s methionine content is also on the low side relative to most other beans.

Fava Bean Amino Acid Profile

Fava beans have the worst amino acid profile of any bean on this page:

 RDARDAFava Beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280122
Threonine (mg)151050459
Isoleucine (mg)201400520
Leucine (mg)392730972
Lysine (mg)302100826
Methionine (mg)151050105
Phenylalanine (mg)251750546
Valine (mg)261820575
Histidine (mg)10700328

Compared to other foods in general, they’re still good nutritionally, but other beans are almost always a better choice.

Fava beans take more than 2 servings to reach the RDA in tryptophan, isoleucine, leucine, lysine, methionine, phenylalanine, valine, and histidine.

So basically all of them…

Lima Bean Amino Acid Profile

Finally, we have the amino acid profile of lima beans:

 RDARDALima Beans
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280139
Threonine (mg)151050540
Isoleucine (mg)201400623
Leucine (mg)3927301035
Lysine (mg)302100976
Methionine (mg)151050190
Phenylalanine (mg)251750779
Valine (mg)261820610
Histidine (mg)10700400

It also has one of the weakest overall profiles.

It’s low in leucine, lysine, methionine, phenylalanine, and valine.

It’s still good to add to meals, but I wouldn’t heavily rely on it over other beans if possible.

Lentils Amino Acid Profile

I didn’t realize until after I originally published this that I also should have included lentils on the list.

So here is essential amino acid profile of lentils, better late than never.

 RDARDALentils
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280160
Threonine (mg)151050640
Isoleucine (mg)201400772
Leucine (mg)3927301,295
Lysine (mg)3021001247
Methionine (mg)151050152
Phenylalanine (mg)251750881
Valine (mg)261820887
Histidine (mg)10700503

Lentils have a similar profile to all other legumes.

Most RDAs can be reached in 2-3 cups of cooked lentils, but they’re quite low in methionine.

Garbanzo Bean (AKA Chickpea) Amino Acid Profile

Another one I forgot was chickpeas, despite it being the bean that I eat the most myself.

Here’s the essential amino acid profile for garbanzo beans (which is a different name for chickpeas, but the same):

 RDARDAChickpeas
 mg per kgfor 70 kg person1 cup
Tryptophan (mg)4280151
Threonine (mg)151050491
Isoleucine (mg)201400745
Leucine (mg)392730909
Lysine (mg)302100765
Methionine (mg)151050116
Phenylalanine (mg)251750571
Valine (mg)261820723
Histidine (mg)10700393

As expected, they follow the same trends as most other beans.

Decent for most amino acids, but very low in methionine. However, they’re also relatively low in leucine, and phenylalanine compared to other legumes.

Summary

You can reach your RDA for most essential acids with 2-3 servings of most beans.

The exception is that certain beans are low in valine and leucine, and that all beans are low in methionine.

The best beans overall are soybeans, followed by kidney, black, navy, and adzuki beans, which all have similar amino acid profiles.

Fava and lima beans had by far the weakest amino acid profiles, with mung beans not too far behind.

If you want to diversify your protein sources, here’s a list of the best vegan sources of protein.

Finally, protein isn’t everything. If you want to see more about what else beans have to offer, see my bean nutrition comparison.

About the author

Dale Cudmore

Your friendly neighborhood vegan from Toronto. Chemical engineer turned semi-professional soccer player and freelance nutrition writer. I've been vegan for years and try to make life easier for others by sharing what I've learned.

11 comments

  • Hi Dale,
    Thanks for the article and for the other faqs! It is super useful for planing a diet without supplements. Am I getting right that the numbers under the amino acids’ names in the first table are the amounts of servings needed to cover the RDA but not grams (g) as stated in the header of the table?

    • Great point Mark, you’re the first to catch that mistake – whoops!

      You are indeed correct, it’s number of servings, those headings should not have grams in them.

      For anyone confused by this comment, I’ve updated the image so that it’s correct.

  • Hello Dale,

    Thank you for this useful information. Where did you get it from? I’d like to look up the amino acid profile of cereals too so I can work out good protein combining for a vegan diet. If you can advise on where to get that info, or whether someone has already done it that would be amazing!

    Zara

    • Good catch Pao! Not sure how that happened.

      I’ve updated the values (the lentils were wrong), thanks for pointing it out.

  • Hi Dale!
    Thank you for the article, it was a very useful tool, especially since 70 Kg is approximately my weight.
    However, I was curious whether the cup serving size refers to dried or cooked beans and legumes.
    Do you know, which it’s referring to?

    Thanks again!