Okay, here it comes, the ‘Palo’ question. Now I do not want to offend anyone nor do I wish to disparage a diet system that has been of great help to many people but…
The Paleo Diet claims that beans and lentils should be excluded from the diet because they contain anti-nutrients. (Chapter 7 of my book, Phytonutrient Gardening covers anti-nutrients in more detail.) This is due to substances called Phytic acid, tannins and oxalates.
- Phytic acid, while in many cases reduces some small amount of micronutrient absorption, is just as high in nuts as in legumes, and yet nuts are not excluded from the Paleo Diet.
- Tannins are just as high in wine.
- Oxalates are just as high in spinach, but these are not excluded from the Paleo Diet either.
The anti-nutrient higher in legumes than other foods are lectins, natural phytonutrients that plants use as insecticides to protect themselves. Lectins break down the membranes of insects thus helping the plant to survive. When we eat the plant the Lectins work in our bodies to break down the membranes of hurtful invaders like cancer cells, reducing prostate, colon and other cancers in research tests. Furthermore, fungi, bacteria and viruses, and yes, even the HIV-1 retrovirus are combated by these Lectins. This is a big part of why tomatoes, corn, whole grain rice, wheat, oats, nuts, sunflower seeds, peaches, mangos, grapes, cinnamon, citrus, berries, tea and most other plant foods are healthy, they all contain significant amounts of lectins!
It is true however, that when there are VERY large amounts of lectins in our food, we start to feel the effects of their hurting the membranes of the cells lining our intestine the same way they hurt cancer cells and bacteria. So guess what this means? It means that as with everything in life, too much of a good thing can become a bad thing!
We have known for over half a century that lentils and beans have the highest levels of lectins and therefore can make us sick if we eat them raw. We also know that cooking beans for 15 minutes at 212F completely denatures lectins. What’s more, canning beans is just as effective, meaning cooked and canned legumes are not only completely safe but that their residual lectin levels fight cancer, fungal problems, and bacterial infections. Who doesn't want that?
Other studies have shown that people who have intestinal issues with properly cooked legumes are, more often than not dehydrated, usually because of high levels of exercise with insufficient salt consumption, or else low levels of exercise with too high salt consumption. Understand that 1/4 of the starches in legumes digests very slowly so if a person's digestion is compromised for any reason, such as being dehydrated, a significant amount of legumes are not digested until intestinal bacteria digest them, thus producing gas. Legumes are therefore the ‘canary in the coal mine’ for poor digestion capacity. Avoiding legumes because digestion is hindered from high salt and low water consumption (typical in the US) is the wrong solution. This would be like pushing harder on the gas pedal in your car because the transmission is going out, it makes no sense at all. You SHOULD eat conservative portions of legumes regularly, ideally EVERY DAY, for the highest levels of health, weight loss, and performance. Many cultures in the world (Southeast Asia and the South Americas) have had extremely high levels of health eating lentils and beans, but are now fairing worse as our modern Western ways of eating have taken over.
Since legumes are almost always eaten cooked, saying they are unhealthy is almost always incorrect. The Paleo Diet says to eat as much meat as you want, even though choking down a steak without cooking it could hurt you. And the 'Paleo people' often respond with, “Oh, come on Joe, no one eats meat that way". This is true but then no one eats legumes uncooked either! Drinking 3 gallons of water all at once would kill you in minutes (it dilutes electrolytes around neurons too much), but no one drinks water that way. Eating a gallon of spinach every day would give you kidney stones within 10 years (oxalic acid), but no one eats spinach that way.
It seems to me that we should all work together to discover what range of consumption of all foods is ideal, rather than using selected scientific studies to argue back and forth as if one viewpoint is absolutely correct, when it rarely, if ever, is. In the case of legumes, eat them every day as part of a healthy diet, avoid them raw, and stay hydrated. Problem solved! Just keep in mind that there are many different types of legume lectins. One of the most well-researched of all the lectins is called phytohemafflutinin, found in many types of beans, especially in red kidney beans.
Phytohemagglutinin is toxic in high amounts, and several incidents of poisoning have been reported after consumption of raw or improperly cooked red kidney beans. In most other edible legumes, the amount of lectins is not high enough to cause any symptoms in most humans. However, as a general safety rule, dry beans should never be eaten unless properly prepared and fully cooked.
I eat beans and I think you should too! Legumes are linked with various health benefits. They have impressive nutritional and phytonutritional profiles, and they are one of the best plant-based sources of protein known to man.
At the end of the day, properly prepared legumes are very healthy when consumed as part of a balanced diet. Just remember the old adage “Everything in moderation,” and you will be fine. “Everything in moderation” is most difficult for me when it comes to my favorite beans of all – Jelly Beans! (OK, yes, jelly beans are a candy and not a healthy legume but, man, I love jelly beans!