Can Legumes Be Safely Eaten By Those With Graves’ Disease and Hashimoto’s Thyroiditis?

In past articles and blog posts I’ve discussed the difference between a “standard” paleo diet and an “autoimmune” paleo diet.  A standard paleo diet allows someone to eat vegetables, fruits, nuts, seeds, meat, fish, and eggs.  An autoimmune paleo diet is even more restrictive, as nuts, seeds, eggs, and the nightshade vegetables are also excluded from this diet.  Of course with either diet you want to avoid refined foods and sugars, and you’ll also notice that grains aren’t included in either diet.  But the focus of this post is going to be on legumes, which are also excluded from both a “standard” paleo diet and an autoimmune paleo diet.

Which Foods Are Considered To Be Legumes?

Legumes include beans, peas, lentils, peanuts, and other podded plants.  The following are some of the more well known legumes:

Black beans

Garbanzo beans (chickpeas)

Green beans

Jelly Beans (just kidding)

Kidney beans

Lima beans

Navy beans

Pinto peans

Soybeans

Lentils

Miso

Dried peas

Peanuts

Why Are Legumes Excluded From Both A Standard And An Autoimmune Paleo Diet?

So why are legumes excluded from both a standard and an autoimmune paleo diet?  After all, there are numerous health benefits of legumes, which I’ll list below.  But even though this is the case, the primary reason why legumes are excluded from these diets is because they have compounds that can interfere with nutrient absorption and increase the permeability of the gut .  And some researchers theorize that a leaky gut is a characteristic of all autoimmune conditions.

What Are Some Of The Health Benefits Of Legumes?

Even though legumes are excluded from both a standard paleo and an autoimmune paleo diet, they do have numerous health benefits:

1. They are a good vegetarian source of protein. For example, one cup of lentils has approximately 18 grams of protein. Most beans are also a good vegetarian source of protein.
2. They are a good source of fiber. One serving of beans provides two to four grams of fiber.
3. They are a good source of certain vitamins and minerals. Beans are an excellent source of folate, and zinc bioavailability from legumes is relatively good (1). Although beans are high in iron, the bioavailability from legumes is poor (1).  Many beans are good sources of calcium, and while the bioavailability is lower than from milk and green leafy vegetables, it is still pretty good (1).

What Are Some of The Risks of Eating Legumes?

Although there are health benefits of eating legumes, there are certain health risks as well.  Most legumes have bioactive compounds such as lectins, saponins, and enzyme inhibitors (2).  These can interfere with the absorption of nutrients, and can also lead to an increase in intestinal permeability.  However, this doesn’t mean that everyone who eats legumes will develop nutrient deficiencies or a leaky gut.  Most healthy people who eat small amounts of thoroughly cooked legumes probably shouldn’t be too concerned.  Sprouting legumes might also help to reduce some of these compounds.  However, according to Loren Cordain’s research, cooking doesn’t completely eliminate lectins, and soaking, sprouting, or cooking doesn’t reduce saponins.

In the previous paragraph I mentioned how most healthy people probably can eat small amounts of thoroughly cooked legumes, but how about someone who has an existing thyroid or autoimmune thyroid condition?  Should these people avoid legumes?  Well, it does seem to depend on the person.  Many will argue that people with autoimmune conditions such as Graves’ Disease and Hashimoto’s Thyroiditis should avoid legumes, along with other foods that can have a negative effect on the health of the gut.  And while I do initially recommend for my patients with autoimmune thyroid conditions to avoid these foods, some people are able to reintroduce legumes and other foods without a problem.

What’s The Deal With Peanuts?

I personally love most nuts and seeds.  Although peanuts are actually a legume, I still tend to categorize them with nuts.  And if peanuts were considered to be healthy I would be eating them on a regular basis.  But while I think that both peanuts and peanut butter are delicious, you really do want to minimize your consumption of these.  This isn’t to suggest that peanuts have no health benefits, as they do have some good nutrients, and they might have cardioprotective effects (3) (4).  One study even showed that peanut butter consumption can lower the risk of developing type 2 diabetes (5).

However, while peanuts have some health benefits, they are highly allergenic.  In addition, peanuts are also high in aflatoxins (6) (7).  Aflatoxins are fungal metabolites which can have a negative effect on our health.  And so even if someone doesn’t have a peanut allergy or sensitivity, the aflatoxins can have a negative effect on their health.  Cyrex Labs has a test called the Chemical Immune Reactivity Screen, which measures the immune system response to certain chemicals.  And it does test for aflatoxins.

Legumes Are High In FODMAPs

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, and I’ve written a separate blog post entitled “Should People With Thyroid Conditions Follow a low-FODMAP Diet?“.  Most legumes are considered to be high FODMAP foods due to the non-digestible galacto-oligosaccharides (8) (9).  Those people with small intestinal bacterial overgrowth (SIBO) don’t do well with high FODMAP foods, and so if someone has SIBO then they probably won’t be able to tolerate legumes, although some people with SIBO are able to consume small amounts.

In summary, legumes include beans, peas, lentils, and peanuts, and they are excluded from both a “standard” paleo and an autoimmune paleo diet.  The main risk of eating legumes is that they have compounds which can interfere with nutrient absorption and increase the permeability of the gut.  However, this doesn’t happen in everyone, and legumes also have some good health benefits.  So while some people are better off avoiding them, others do fine consuming thoroughly cooked legumes in small amounts, and this includes some people with Graves’ Disease and Hashimoto’s Thyroiditis.  The problem is that it’s impossible to predict who will do well when consuming legumes and who won’t do well, and this is why I do have most of my patients with autoimmune thyroid conditions avoid eating legumes while trying to restore their health.