If you’ve read our articles or heard us speak, you know we don’t base our nutritional recommendations primarily on what Paleolithic man may or may not have eaten. We care about whether the foods we’re eating here today are making us more healthy or less healthy. So the reasons we cite for avoiding legumes, much like our rationale with grains, dairy, and sugar, have far more to do with health than history. (It just so happens that health and history – and our genetics – are inextricably linked.)
Legumes are a botanical family of plants that include dozens of varieties of beans, lentils, garbanzos, peas, and peanuts. Yes, that also includes soybeans, which the multinational agriculture conglomerates have figured out how to grow in (unnatural, unsustainable) monocultures by the megaton – and market them in a pretty effective way to the American public. (An aside: the coffee , cocoa, and vanilla “beans” are not, botanically speaking, legumes, and thus are excluded from this particular discussion.) Legumes are often used as “cover crops” because of their ability to “fix” nitrogen in the soil, improving fertility of the soil for subsequent crops. Historically, they were primarily used as an agricultural tool, not as food. Hmmm.
The Case for the Bean
Owing to their nitrogen content (i.e. protein), legumes are often recommended as a healthy dietary choice, especially for vegetarians. Proponents of legumes cite their dietary fiber, vitamins and minerals, and “high” protein content, and may even reference observational studies that “show” that legumes are healthy. Let’s address the potential benefits of legumes one by one.
First, you might already know that foods other than beans – such as ample amounts of vegetables and fruit – offer us plenty of fiber. In addition, dietary fiber isn’t as important as you might think, in the context of a healthy diet that is not promoting gut damage. In summary, eating legumes for fiber is like eating a Mounds bar for the coconut – lots of potential down sides (which we discuss in detail below) for a small potential benefit.
In terms of micronutrient density, legumes come up short when compared to vegetables and fruit. (The lack of nutrient density in beans compared to green leafy vegetables like kale is so glaring that we can rest our “beans are nutritious” case here.)
Finally, we don’t think we need to make a lengthy argument that legumes are an inferior source of protein compared to meat, seafood, and eggs, and that regularly consuming animal protein is your best bet to supply dietary protein (i.e. those amino acids that your body builds into your structural “stuff”). Just in case… legumes offer an incomplete amino acid profile, meaning that they do not supply all essential amino acids in biologically useful amounts. In addition, some of the proteins that are technically present in the legumes are poorly digestible, and thus not available for use in your body.
Digging Deeper – The Legume Downside
So legumes aren’t as awesome as the marketing might make you think. Is that really a good enough reason to ditch them altogether? Worse than simply being an inferior source of dietary protein and an unnecessary duplication of the dietary fiber supplied by the micronutrient-dense vegetables and fruit we recommend, legumes do have some major downsides – enough that we think you should keep them off your plate.
First, while legumes do contain some protein, they also contain significant amounts of carbohydrate – often several times that of the amount of useable protein. We are certainly not carb-o-phobic, but the amount of carbohydrate you’d take in using legumes as a primary protein source would mean that you were (a) not getting enough (bioavailable) protein in an attempt to limit your carbohydrate intake to a healthy amount, or (b) taking in unhealthfully high amounts of carbohydrate to get as much protein as you need. (Or, potentially, both.) And though the carbs found in beans are low glycemic index, your body still has to secrete significant amounts of insulin to manage the relatively large amounts of blood sugar – and with insulin, like many things in your body, a little is good, but lots is… not.
Second, legumes as a general botanical category are toxic if consumed raw. Literally… toxic. The problem is that usual preparation methods of prolonged soaking and rinsing, cooking, sprouting, or fermenting only partially neutralizes those toxic substances, generally referred to as lectins. (There are other harmful substances in legumes, but we’ll stick with lectins for now.) Lectins are plant proteins that are very resistant to digestion in the stomach and small intestine. They arrive (and hang out) in the small intestine largely intact, and do some pretty dirty work there. Lectins such as phytohaemagglutinin create damage to the wall of the small intestine (which increases gut permeability) and causes an imbalance of gut bacteria. P.S. Increased gut permeability is never a good thing.
If your gut integrity is compromised, that means that the immune tissue located in your gut is exposed to large amounts of potentially inflammatory substances, including those lectins. Regular exposure to lectins can promote inflammation in the digestive tract, but also elsewhere in the body (since those little buggers punched holes in your gut and can get virtually everywhere via your bloodstream). Long story short: the fewer intact foreign proteins (including lectins) circulating in your bloodstream, the better. Foreign proteins in your bloodstream cause systemic inflammation. Boooo.
Specific to Soy
A third concern, specific to soybeans and even moreso with processed soy products, is the content of compounds that behave like estrogen (that female sex hormone) in the human body. These compounds, classified as phytoestrogens (or “isoflavones”), bind to and stimulate – or, in some tissues, block – estrogen receptors. And while the overall research on soy products is conflicting and inclusive due to the gender-and tissue-specific effects of phytoestrogens, there are, in our view, some alarming issues related to the consumption of soy and soy products. In women, phytoestrogens have been linked to longer and more painful menstrual periods. For guys, soy intake decreases sperm count. And studies suggest that children fed soy-based formulas may be at risk for compromised immune systems later in life. So while the research may not be cut and dried, we think you shouldn’t mess with your delicate sex hormone balance at any age, and ingesting phytoestrogens in an unknown “dose” via soy products do just that.
As an aside, edamame (the unprocessed soybean) is not your best choice for everyday consumption, but processed soy products, including soy protein concentrate/isolate and “texturized vegetable protein”, are extra-bad choices for multiple reasons. In fact, the more processed forms of soybeans, like tofu, are an even more dense source of the phytoestrogens and other antinutrients than their unprocessed counterparts.
For Vegetarians
For vegetarians who are morally or ethically opposed to using animal proteins for their amino acid supply, legumes might be a “necessary evil”, since legumes – specifically soy – are some of the densest plant source of protein. However, understand that from our view, legumes won’t come anywhere close to supplying the right amount and proportion of amino acids for optimal health. (The argument is often made that some groups of people survive while eating legumes, but that doesn’t mean that legumes are your best choice to thrive.) If you’re a strict vegan, your best bet is to practice traditional preparation methods of soaking, rinsing, sprouting, fermenting and prolonged cooking, to partially break down some of those inflammatory lectins, and to rely on more dense sources of protein (less processed soy products like tofu and tempeh) that offer more grams of protein without so many accompanying carbohydrates.
The Wrap-Up
In summary, the claimed benefits of legumes aren’t quite what they’re heralded to be, and there are significant downsides to legume consumption. Yes, there are ways to make them “less bad”, but why work so hard to continue to eat things that in the end still aren’t that healthy? While prolonged soaking, rinsing, cooking and fermenting legumes neutralizes some of the lectins, we still don’t think that they offer enough in terms of micronutrition (vitamins, minerals, and beneficial phytochemicals) to justify regular consumption. And while the jury may be out on the long-term effects of phytoestrogens, we recommend generally avoiding legumes as part of your healthy, Eat-Good-Food diet.
Now why did you have to go and attack Mounds bars?
Other than that, great article and it’s good to see so many links to medical research with all of the statements.
I’m so glad you all have posted this manifesto. Legume consumption is the part of Paleo/Archevore/Primal eating I struggle with the most. I am an avid organic gardener and rely on pea and green bean rotation for good soil recovery. I also eagerly await my first pea crop as a harbinger of spring. I eat those peas raw, right out of the pod. Sometime I’ll cook them with ghee and mint. But, they are mostly a spring treat since they are a cool season crop. When they’re done producing I rotate in another vegetable.
I can botanically understand the case against dried legumes as I suspect lectins serve as an antiherbivory strategy. But, spring peas are like a tonic. I also eat green beans raw, right off the vine. They are a staple in my organic garden. When I read stuff about legumes, most often dried legumes are referenced. Would you please provide more references on fresh pea and green bean research?
Very nice, concise, easy to understand post. I’ll have to use this as my go-to web site to send people who ask me “but WHY don’t you eat beans? Aren’t they HEALTHY?”
Once I master cashew “hummus” and sunflower seed “refried beans,” I won’t even miss beans a little bit. =]
Amanda, just make Baba Ghanoush instead of hummus. You will never look back.
Easy+awesome recipe here: http://theclothesmakethegirl.blogspot.com/2009/07/eat-your-vegetables-eggplant.html
Leslie,
We make a special case for three “legumes” that are common “vegetable” choices – green beans, sugar snap peas and snow peas. It’s not based on scientific research, because we haven’t been able to find any to support or deny the inclusion of those three legumes in our diets. We’re just going with good, old-fashioned common sense in this case.
Our issue with legumes come when you eat the fully developed, mature seed, like with edamame or black beans. (It’s not about whether it’s dried or not – think edamame, which isn’t dried but is the fully developed soybean “seed”, and therefore makes our “do not eat” list.) The seed itself is what contains the compounds mentioned above that provoke inflammation in the body. When you’re eating most legumes, you’re eating the mature seed itself.
The three examples above – green beans, snow peas, sugar snap peas – don’t exactly fit the profile. For one, the “seeds” are not fully developed or mature – they’re still very small and in the pod. Two, there’s far more green vegetable matter (pod) than there is seed (bean) in every bite – and we have no concerns about eating the vegetable matter.
Though we don’t have any scientific evidence of a smaller gut-binding lectin content in those three legumes (due to their less-than-mature status), we also include a healthy dose of common sense in our decision-making process, which is why we leave the green bean, snow pea and sugar snap pea on our shopping list.
In summary, if green beans are the worst thing in your diet, you’re doing pretty darn well. Thanks for the question.
Best,
Melissa
Thanks Melissa! I can dig that, pun intended. Always appreciate your common sense approach.
Cheers, Leslie
Thanks so much:D I have so many people asking for an explanation (including my own family) on why I do not consume legumes……Now I have some where to point them to:D
Beans are definitely not a major part of my diet, but I do save them for special occasions. I’ve a friend who makes this absolutely delicious three-bean vegetarian chili, & there’s no way I’d pass that up. Personally though, I don’t understand how anyone could stomach them in the amounts CW has been touting them lately. My tummy is not happy if I eat too many…
Here’s my question/concern – first off, a little background – I’ve struggled with getting down to a “healthy” weight for most of my life…I’m 5’9″ and spent most of my adult life hovering around +/- 200 lbs, I’m finally down to 170-175, still trying to get down a few more lbs – and the way I was able to accomplish this was by starting the 4 hour body diet (slow carb) from the book – which requires significant amounts of beans. The first thing I noticed was how full and satieted I was after eating a large protein and beans meal.
I eventually got to a point though where (I believe) the beans were catching up with me, and causing a LOT of intestinal discomfort/distress (you know, gas)…I then transitioned to a more “paleo” diet and have felt amazing since.
Here’s where my concern comes in…being Puerto Rican, beans are a staple in my family’s diet. Rice and beans have been traditional (and delicious) meals all growing up – is there a way to safely incorporate this type of eating (minus the rice, the rice never did much for me, it was always the beans!) and still follow a primarily paleo lifestyle. Aside from an occasional meal of beans that is.
The other issue is the discussion of not strictly looking at diet from a historical perspective – but since many cultures have had to rely on beans for sustenance, makes me wonder how non-beneficial they could be. Are you saying they are strictly beneficial from an agricultural aide (for maintaining nitrogen content, etc…) in soils?
I know I’m rambling a bit, and I apologize for that but I really enjoy your posts, and you’ve absolutely decimated two of my faves – beans and peanuts/peanut butter!
Brian
This is a very badly supported article. I just looked at the one paper they cite for intestinal bacterial imbalance, and not only are they coming to a conclusion about one component (lectin) of a kidney bean, but they are also talking about the purified version of that component. (Lectin in red kidney beans is a known toxin when they are raw, or if you were to eat tons of them and only that). This is like saying sugar is not the best thing for you so you shouldn’t eat fruit. Purified sugar, especially if you were to be fed a diet of it, is a terrible idea! However, your body needs sugar to function properly, and ingested in the right amount not only is it essential for energy and growth, but actually good for you. The sugar in fruits is one of the healthiest way to get your nutrients as well. Also, this particular article about the kidney beans – as an example – is from 1985, and has only been cited twice since then! An upstanding and well-represented article would have thousands of citations by now. Many of the few citations in the article are from studies conducted on baby rats, not humans. Furthermore, beans eaten in combination with rice DO give complete protein. The way I see it, I would never be eating only beans, just like I would never be eating only meat, or animal products. No one should.
Passing along this kind of thinking without doing the adequate background research is probably not a great idea (this was written by people promoting a diet – not for the well being of the general public -> ie. they have a vested interest in swaying your opinion). You should all be focusing on the plethora of scientific evidence pointing to the detrimental effects of eating processed foods and those with trans and lots of saturated fat – ie. crap most people buy from the grocery store – cookies, cakes pies butttttter (tarts), milk chocolate, chips, pop….. SORRY! but you cannot argue with the overwhelming scientific evidence (and evidence of our own eyes!) that eating these things are bad for us.
With all my love and compassion,
L
L – why couldn’t you give your name? Since people on the Paleo diet don’t eat processed food, we try and improve our diet even more. Why should they write in this article about the dangers of processed foods?
Where’s your scientific proof that rice and beans are a “complete” protein. You don’t quote anything.
They also don’t say eat fruit, they love fruit. Obviously you know nothing about the Paleo diet and just want to be a hater. good luck with that.
phytohaemagglutinin sounds interesting. Thanks for providing a reference too. I love beans based foods, like chickpeas, baked beans, bean salad. Though I am in agreement with the high carbohydrate issue, especially when it comes to weight loss. Thanks for the post. You have given me something to consider this evening.
Just a quick question… are bean sprouts included as a legume (the fresh, white ones, no bean attached)? I’m on day 5 of my whole 30 and I just put some in my stirfry last night… should I not have? I noticed a few other sprouts mentioned on the list of recommended veggies, but bean sprouts aren’t mentioned. Thanks you guys! I’m loving the website!
Jillian, the sprout part of legumes are A-OK – it’s the seed (the “bean” itself) that we’re citing above. Sprout away – I like pea shoots myself.
Best,
Melissa
Hi! I have just found your website and I’m in love! Digging the no-nonsense approach and seriously thinking about a Whole30. I love a good challenge.
Here’s my issue…like the above commenter, I’ve lost a good deal of weight doing 4 Hour Body. I’ve also incorporated running (currently training for a half-marathon) and Bikram. As it stands, I can barely choke down enough beans to get sufficient carbs for my runs. The thought of being able to forget about them altogether is tempting, but where in the world am I going to get the energy for a 10 miler?
Thanks!
A few disagreements to note:
1. Vegans and vegetarians (when consuming a varied proper diet) do not need to be concerned about the incomplete protein content of legumes as they obtain the other essential amino acids from other food sources in a day. This is only a problem for people who eliminate animal protein and do not replace with other healthy, whole food alternatives.
2. The research is still conflictual regarding soy phytoestrogens. There is a lot of thought that phytoestrogens may actually be beneficial in blocking receptors in the uptake of excessive estrogen which we all generally take in such as xenoestrogens from plastic containers, birth control pills (and subsequent residue in our water) and estrogen present in animal protein which is far higher quantities than what would naturally occur in a human body. Further, the research is generally stating that the quantity of soy intake for a male would have to be so high to alter any testosterone, progesterone or other endocrine levels that they would need to take in cartons of soy milk a day.
3. The body is able (and designed to) process carbohydrates, including high glycemic ones (obviously). Not all high glycemic carbohydrates are bad when they are balanced with fibre and protein (which lowers the overall GI level). Yes people can derive energy from fat however carbohydrate is the only clean burning energy source (no residue to be filtered by the body) and the only source that the brain can synthesize. While I agree that a head of kale is a great source of carbs (and protein for that matter but that point is usually overlooked), the intake of carbohydrate in the form of properly prepared legume in ratio with other protein and fat sources is a reasonable balance.
4. Digestive tract inflammation and gut permeability are a great concern however other foods such as animal proteins tend to be difficult to digest, require a large amount of metabolic energy to process, have a high level of residue which must be filtered by the kidneys and is acid-forming in terms of blood pH which leads to inflammation. My point here is mainly that there are many types of food that contribute to intestinal permeability and inflammation not just legumes. Even the way in which people consume their food, such as improper food combining and eating too quickly resulting in large particles entering the small intestine contributes to this problem.
All of the above being said, if people are going to have legumes (soy included), they need to make sure of the following:
1. The legumes are organic and non-gmo
2. They are properly prepared i.e. soaked and sprouted prior to cooking for proper digestion and assimilation
3. Some legumes have been stored a long time (i.e. peanuts) and contain a mold content that is allergenic so again the source and quality is important
I think it is dangerous to advise people to eliminate any one type of unprocessed whole food from their diet because it is a slippery slope so to speak. Grains can be be problematic, legumes can be problematic and research is even questioning/suggesting that fruit is also problematic due to high fructose content and being high on the GI scale. When we eliminate so much natural food, we greatly reduce our nutrient profile in many areas leading to imbalances and deficiencies. The message people need to be getting is to not eat any one food in abundance, but to consume all natural, alive, good quality foods in rotation and balance while being thoughtful of the source.
I have a question about soy. We’ve signed on to the idea of eliminating legumes from our diet, but in looking for a replacement I bought “liquid aminos” as I had seen it in several Paleo recipes, but the label says “contains soy protein”. So, basically I want to know is soy protein ok? And if not, do you have a suggestion for a paleo soy sauce replacement?
Thanks!
I came across this article by Dr. Clyde Wilson refuting the claims about lectins still being present in the majority of canned and cooked legumes.
http://www.drclydewilson.com/content/paleo-diet-incompetent-new-level-legumes-are-not-antinutrients
Has this criticism been voiced before about the exclusion of legumes? I didn’t go to check the original scientific studies he referenced myself, but was wondering if any of you Whole9 bloggers had seen this article yet, and if you had any responses.
There’s still the carbs factor here, but it’d be nice to know whether or not the lectins reason is truly a reason to stay away from legumes at all.
I love hummus and eat a large amount of it for the protein……is this a “no..no” ??
Andrew D,
Sorry I missed your comment when you originally posted it. Dr Wilson, if perhaps abrasive and condescending, is correct in that proper preparation (high-temp cooking, fermentation, etc.) does destroy a large amount of the lectins in legumes. We’re actually revising our perspective on legumes in general, as our understanding of the lectin-specific problems have evolved. Here’s the super-short summary on legumes: lectins do not appear to be the primary issue with many peoples intolerance to legumes, and lectins are not as great of a problem as they were previously thought to be. However, there are other compounds in legumes that (experientially) still cause us to recommend against them. It may be fermentable oligosaccharides (FOS) or other problematic compounds, but we continue to make the same recommendations, even if the rationale is slightly altered. Then there’s the phtic acid issue, which is still a downside of legumes, as well as the carb density that you mentioned. If you LOVE legumes, small servings occasionally won’t kill you, but they’re a LONG way from a Superfood. Hope that clarifies things somewhat.
Brenda,
Hummus is a long ways from an optimal protein source, for several reasons (discussed above). Animal protein sources are generally a better option. Try a few weeks without all legumes and see how you feel. If you’re up for it, jump on board our Whole30 program: http://whole9life.com/category/whole-30/
Best,
Dallas
Is sprouted wheat okay? I occasionally eat Ezekiel English muffins, made from sprouted grains, half at a time. I have eliminated other forms of wheat but do occasionally enjoy these.
Gail,
You’re going to want to read our Grain Manifesto as well: http://whole9life.com/2010/03/the-grain-manifesto/
While traditional techniques like soaking, rinsing, prolonged cooking, sprouting and fermenting partially break down some of the inflammatory and anti-nutrient compounds, the key words are “partially” and “some.” In addition, sprouted grains are just as carb-dense and nutrient poor as their non-sprouted counterparts. We think they’re still not a good choice for everyday food.
Best,
Melissa
You refer to tofu as both more highly processed and less processed. Which is it?
You have this:
“In fact, the more processed forms of soybeans, like tofu, are an even more dense source of the phytoestrogens and other antinutrients than their unprocessed counterparts.”
and this:
“… more dense sources of protein (less processed soy products like tofu and tempeh) that offer more grams of protein without so many accompanying carbohydrates.”
I am a lacto-ovo-vegetarian and not willing to eat animal protein after many years of not doing so, and thus don’t think I can follow this completely in any case, but wanted to understand your take on where tofu fits into the legume picture.
Barb,
Sorry for the confusion. The phrases should be taken in context.
Tofu is more processed than the edamame (raw soybeans) we were speaking of in the first paragraph. If you’re eating soy products, however, tofu is a less processed alternative than, say, Gardenburgers or Tofurkey. (In retrospect, I could see how you would be confused.)
We just recently outlined our full recommendations for vegetarians and vegans in the upcoming Paleo Summit. You can register here (http://www.1shoppingcart.com/app/?af=1431398) and receive notification when our interview will be available for free on their web site. That should help you understand our plan for those who eat little to no animal products.
Best,
Melissa
Thanks for the speedy response.
this is a really badly written article. the first half is total fluff. ya beans contain carbs. so what? if you replace something shitty and gross like a twinkie or white bread with beans for you evening meal its not going to ever be unhealthy.
@suna
of course beans aren’t as bad as a twinkie. that’s not the point of the article. the point is to cut things out of your diet that aren’t giving you the benefits you think (and come with a bunch of bad!)
a gunshot wound is worse than a puff from a cigarette. that doesn’t mean that the cig isn’t bad for you.
U obviously smoke since u just said “cig”