Can Nuts and Seeds Cause A Leaky Gut?

Nuts and seeds are my favorite snack.  I love eating cashews, almonds, walnuts, pistachios, sunflower seeds, pumpkin seeds, as well as other nuts and seeds.  However, nuts and seeds are excluded from an autoimmune Paleo (AIP) diet.  But why is this the case?  In this blog post I’ll discuss why nuts and seeds are excluded from an AIP diet, and when you can safely reintroduce them back into your diet.

In a blog post I wrote in 2014 entitled “Can Eating Nuts and Seeds Be Detrimental To Thyroid Health?“, I discussed the health benefits of many of the different nuts and seeds.  As a result, I don’t plan on discussing this here, as if you’re interested in learning about the health benefits of the different nuts and seeds you can simply refer to this past article.  In this current article I want to focus more on why nuts and seeds are excluded from an autoimmune Paleo diet, and whether they SHOULD be excluded.

The Problem With Eating TOO MANY Nuts And Seeds

There is no question that nuts and seeds have some good health benefits, which is why they are part of a standard Paleo diet.  However, you do want to be cautious about eating too many nuts and seeds due to the following five reasons:

1. Nuts and seeds are high in omega 6 fatty acids.  Although omega 6 fatty acids get a bad rap, it’s normal to have a higher ratio of omega 6 to omega 3 fatty acids.  The problem is that in most people the ratio is way too high.  In most cases this isn’t due to eating too many nuts and seeds, but instead is due to eating too many processed foods, including fast food, unhealthy oils, etc.  However, eating a lot of nuts and seeds can increase this ratio.  On the other hand, if someone is eating a relatively healthy diet and has an omega 3 index greater than 8%, then eating a few ounces of nuts per day shouldn’t cause a problem in this area.

So based on what I just said, if you haven’t recently tested your omega-3 index then you might want to consider doing so.  Or you might even want to take this a step further and get a complete fatty acid profile.  This not only will look at the omega 3 index, but it will evaluate other markers such as the ratio of arachidonic acid to eicosapentaenoic acid (EPA), the total omega-3 fatty acids, and the total omega-6 fatty acids.

2. Nuts and seeds are higher in lectins when compared to many other foods.  This supposedly is one of the main reasons why nuts and seeds are excluded from an autoimmune Paleo diet.  Lectins are compounds that are present in a variety of plants and seeds, and they serve as a defense mechanism.  They are considered to be a type of anti-nutrient, and besides most lectins being resistant to heat and digestive enzymes, they can bind to different cells and potentially cause damage to numerous organs (1).  There is also a concern about lectins causing an increase in intestinal permeability (a leaky gut).

However, lectins are found in many foods, and so their presence alone doesn’t mean that you should avoid a certain food.  Not all foods have an equal amount of lectins, which is one reason why foods with higher amounts of lectins are excluded from a standard Paleo diet (i.e. legumes), while others such as nuts are allowed.  Finally, there is no evidence I’m aware of which shows that eating nuts and seeds will cause an increase an intestinal permeability.

If this is the case, then why are nuts and seeds excluded from an autoimmune Paleo diet?  To be honest I’m not 100% certain why, but one potential reason why nuts and seeds are allowed on a standard Paleo diet, but are excluded from an autoimmune Paleo diet, is that they can interfere with gut healing.  In other words, while there is no evidence I’m aware of that eating nuts and seeds can cause a leaky gut, eating nuts and seeds might prevent an existing leaky gut from healing.  And according to the triad of autoimmunity, everyone with Graves’ Disease and Hashimoto’s has a leaky gut.

But this might also depend on 1) the quantity of nuts and seeds eaten, and 2) how they are prepared.  If someone with a leaky gut eats a large amount of raw nuts and seeds on a frequent basis then this will make it more difficult for their gut to heal when compared to someone who eats a small amount of nuts and seeds per day and also soaks and sprouts them.  The problem is that many people eat too many nuts and seeds, and most people who eat them don’t properly prepare them.  One can make the same argument with other foods, such as legumes.

3. Nuts and seeds are high in phytic acid.  Phytic acid is the major storage form of phosphorous in cereals, legumes, seeds and nuts (2). One of the main concerns with phytic acid is that it can inhibit the absorption of certain minerals such as iron, zinc, and calcium.  And there is also a concern that large amounts of phytic acid can be a factor in a leaky gut.  However, if someone eats a small amount of nuts and seeds, while minimizing or avoiding other higher sources of phytic acid, such as grains, then they still might be able to heal the gut.  Of course the key word is “might”, as everyone is different, and some people are able to get away with eating small amounts of nuts and seeds, while others will need to completely eliminate them.

It’s also important to note that soaking and sprouting nuts and seeds will dramatically reduce the levels of phytate (3).  So once again, properly preparing nuts and seeds can make them much easier to digest, and reduce both the lectins and phytates, along with other compounds.  One more thing I should mention is that phytic acid does seem to have some health benefits, as some studies show that it can have immunoregulatory effects and decrease proinflammatory cytokines (4).

4. Tree nuts are common allergens.  Although many people are aware that peanuts are a common allergen, many people also have tree nut allergies.  I came across a study which showed that walnuts and cashews are the most allergenic tree nuts in the United States, whereas hazelnut is the most common nut allergy in Europe, and Brazil nuts, almonds and walnuts are the most common tree nut allergies in the United Kingdom (5).  Speaking of peanuts, they are considered to be a legume, which is why they are excluded from both an AIP and standard Paleo diet.  This is also the reason why when a patient of mine asks if they can reintroduce peanut butter back into their diet I try to direct them towards other types of nut butters, such as almond butter.

5. Nuts and seeds are high in oxalates.  Oxalates are small molecules that have the ability to form crystals, which in turn can deposit in different areas of the body, including the thyroid gland. One of the main concerns is that having high levels of oxalates can lead to the development of kidney stones.  While having problems with oxalate metabolism and/or having a yeast overgrowth can lead to high oxalates, certain foods can also cause high oxalate levels.  And unfortunately this includes nuts such as almonds, cashews, and walnuts.  This is yet another reason to be cautious about eating large amounts of nuts on a daily basis.  As for seeds, their oxalate content is high when compared to many other foods, although lower than nuts.  This not only includes common seeds such as sunflower seeds, but chia seeds as well.

I think it’s also worth mentioning that there have been a couple of case reports showing a correlation between oxalate nephropathy and nuts (6) (7). One of these involved cashews, and the other peanuts, which as I mentioned earlier, is actually a legume and not a nut.  An oxalate nephropathy is characterized by extensive calcium oxalate deposition in the renal tubules, resulting in kidney injury (8). Fortunately this condition is rare, and so I’m not suggesting that eating a lot of nuts is likely to result in kidney problems, but if someone does have kidney issues and eats a lot of high oxalate foods then this can be a potential cause to consider.

What’s The Deal With Nut Milks and Nut Butters?

When someone first realizes that nuts and seeds are excluded from an autoimmune Paleo diet, it’s quite common for them to ask me if they can eat nut and seed butters (i.e. almond butter, sunflower seed butter, etc.), as well as nut milks (i.e. almond milk, cashew milk, etc.).  If you are trying to follow a strict autoimmune Paleo diet, then in addition to not eating nuts and seeds, you will also want to avoid all nut milks and nut butters.  After all, nut milks and butters that you purchase at a local store or online will usually consist of raw nuts, and thus will be high in phytic acid and lectins.  On the other hand, if you make your own nut milks and nut butters then of course you have the option of soaking and sprouting the nuts first.  Another advantage of making your own nut milks and nut butters is that you don’t have to worry about some ingredients that are commonly included in these products sold in stores.

Can You Eat Soaked and Sprouted Nuts and Seeds?

For those who aren’t familiar with the process of soaking and sprouting nuts and seeds you can check out this article.  But one question you still might have is whether you can eat soaked and sprouted nuts and seeds when following an autoimmune Paleo diet.  After all, I mentioned earlier how soaking and sprouting nuts and seeds will greatly help to reduce the lectins and phytates.  Although this is true, I still recommend following a strict autoimmune Paleo diet for at least 30 days, which means eliminating the nuts and seeds during this time.  If you are struggling with the diet after this time then I think it’s fine to reintroduce some of the foods you eliminated, include nuts and seeds.

A Brief Explanation of Soaking and Sprouting

Although I realize that some people reading this are already familiar with soaking and sprouting, I’m sure there are others that aren’t familiar with this, and so I’ll give a brief explanation of these below.  I’ll admit that I’m not an expert in this area, and so if you want to learn more about soaking and sprouting there are books and free videos on YouTube where you can learn to do this.  But just as is the case with anything else, the key to becoming an expert is to actually start doing it!

Soaking.  This is quite simple, as you can put your nuts and seeds in a glass jar with water, and add a small amount of sea salt.  When first starting out you might want to begin with a small amount of nuts (i.e. one cup), but once you get into the routine of doing this you’ll probably want to make larger batches at a time.  As for how long you should soak the nuts and seeds, the times vary depending on what you’re soaking. I’d refer to the article I mentioned above, which lists the different soaking times for different nuts and seeds.

Note:  If you want to make the nuts and seeds crunchy after soaking you can put them in a dehydrator for 12 to 24 hours.  If you don’t have a dehydrator you can use your oven, but make sure the temperature doesn’t exceed 115 degrees.

Sprouting. This takes more time, although this essentially just involves soaking the nuts and seeds for longer periods of time, and then rinsing them with water every few hours, or at the very least two or three times per day.  Then within a few days they will germinate and sprout, which further enhances their digestibility and makes them more nutrient dense.  One concern is that mold can form on the nuts and seeds during this process, and to reduce the chances of this happening you want to keep the nuts and seeds refrigerated after sprouting, and dehydrating them will also help to prevent this.  It’s also important to know that not all nuts and seeds can be sprouted.  For example, some of the nuts which can be soaked but not sprouted include walnuts, pecans, Brazil nuts, and macadamian nuts.  Pumpkin seeds and sunflower seeds can be soaked and sprouted.

When Can You Reintroduce Nuts and Seeds?

If you choose to follow a strict autoimmune Paleo diet and therefore eliminate nuts and seeds from your diet, when are you able to reintroduce them?  As I mentioned earlier, for those with Graves’ Disease and Hashimoto’s Thyroiditis, I would recommend to eliminate nuts and seeds from your diet for at least 30 days.  After this point if you are doing well on the diet then it makes sense to continue for a little longer.  On the other hand, if you are struggling with the diet then you can try to reintroduce certain foods.

But you might still wonder when you can specifically reintroduce nuts and seeds back into your diet?  This really does depend on the person.  Sarah Ballantyne is an expert when it comes to the autoimmune Paleo diet, and she has a 4-stage approach to reintroducing foods, which depends on the how most people react to certain foods, and which foods are the most nutrient dense.  In other words, those foods that people are more likely to have a negative reaction to will be reintroduced towards the end, but she also considers the nutrient density of these foods.  Although she does allow seed and nut oils (i.e. macadamia oil) to be reintroduced in stage #1, she doesn’t recommend for whole nuts and seeds to be reintroduced until stage #2.  And certain nuts such as cashews and pistachios shouldn’t be reintroduced until stage #3 according to her reintroduction plan.  I can’t say that I agree 100% with these recommendations, but it’s definitely worth checking out.  Click here to gain access her to free reintroduction quick start guide.

Should You Consider Food Sensitivity Testing For Nuts and Seeds?

Every now and then someone will ask if they should do food sensitivity testing for nuts and seeds instead of eliminating them.  This way they can see if they are reacting to the nuts and seeds, and if this is the case then they can simply eliminate them from their diet.  And if the test shows they aren’t sensitive to them then they can continue eating them.  Although I’m not opposed to food sensitivity testing, there are limitations to this approach.  First of all, food sensitivity testing isn’t perfect, as false negatives are common.  So it’s possible for you to test negative for certain nuts and seeds, yet still be positive.

But let’s assume that you do such testing and everything comes out negative, and it’s a “true” negative.  Just because you don’t have an allergy or sensitivity to nuts and seeds doesn’t mean that they can’t interfere with gut healing.  This is also a limitation of an elimination diet, as someone might feel fine when reintroducing a certain food, but just because they don’t have a negative reaction doesn’t mean that it isn’t interfering with gut healing.

The Final Verdict On Nuts, Seeds, and A Leaky Gut

Many people with Graves’ Disease and Hashimoto’s Thyroiditis are able to successfully reintroduce nuts and seeds back into their diet prior to getting into remission.  However, this doesn’t describe everyone, and when you do choose to reintroduce nuts and seeds I would make sure to do so one at a time.  For example, you can start by reintroducing sunflower seeds, and then wait three days before adding another seed or nut.  If you have any type of negative reaction then stop eating the specific nut or seed, and then wait until your symptoms subside before reintroducing the next one.

Also, while I can’t honestly tell you that I always soak and sprout nuts and seeds before eating them, this can make a big difference in some people.  In fact, when I was dealing with Graves’ Disease initially I didn’t eliminate nuts and seeds from my diet, and while overall I was progressing nicely, I eventually hit a roadblock and ended up eliminating nuts and seeds.  However, I was eating raw nuts and seeds at the time, and so perhaps I wouldn’t have had any problems if I prepared them properly.  Once again, I do recommend for those with autoimmune thyroid conditions to avoid eating nuts and seeds for at least the first month, but when reintroducing them I would strongly suggest soaking and sprouting them.

But how about if you reintroduce raw nuts and seeds and don’t experience any negative symptoms?  Does this mean it’s fine to continue to eat them?  This is where it can get tricky, as I described my situation where I was eating raw nuts and seeds initially when dealing with Graves’ Disease.  I personally didn’t experience any adverse symptoms, but the secretory IgA that was initially depressed remained depressed upon retesting, and didn’t decrease until I stopped eating nuts and seeds.  The point I’m trying to make here is that eating raw nuts and seeds might interfere with gut healing in some people, although you might not experience any negative symptoms when you eat these foods.  Instead you might hit a roadblock like I did.

And if you’re questioning whether my lack of progress was truly caused by eating nuts and seeds, I agree that there is a chance that there could have been another factor which resulted in the secretory IgA not increasing.  However, I’ll add that in the past I did a good amount of leaky gut testing on my patients using the Array #2 from Cyrex Labs, and there were some patients whose gut didn’t heal until they eliminated nuts and seeds.  On the other hand, there were also people whose leaky gut healed even though they continued to eat nuts and seeds.  And while it admittedly can be challenging to make a correlation between someone eating nuts and their gut not healing, it’s still something to keep in mind.

While the focus here is on nuts and seeds, this can also apply to other excluded foods, including eggs, nightshades, and even grains and legumes.  In other words, even if you don’t experience negative symptoms when eating these foods, there is always the possibility that they are interfering with gut healing.  And so if you are following more of a standard Paleo diet and your test results aren’t improving, there is the chance that it’s due to one or more foods that you are eating.  Sure, there can be other factors as well, but before spending a lot of money on additional testing, it makes sense to experiment with eliminating certain foods that can potentially interfere with gut healing.

Should YOU Eat Nuts and Seeds?

If you have Graves’ Disease or Hashimoto’s Thyroiditis, or any other autoimmune condition, then I recommend for you to strictly avoid nuts and seeds for at least 30 days.  If you have a non-autoimmune thyroid condition but have obvious gut issues (i.e. gas, bloating, and/or stomach pain) then I would also eliminate the nuts and seeds for at least 30 days.  But I would also recommend to avoid other foods that can affect gut healing for this 30-day period.

While the autoimmune Paleo diet isn’t meant to be a long term diet, earlier I mentioned that if after 30 days of following this diet you’re thriving then by all means feel free to continue for an extra couple of months.  On the other hand, if you are struggling with the AIP diet, which is common, then feel free to reintroduce some foods.  I usually start my patients with egg yolks (for those who like eating eggs), and I just want to remind you that when you decide to reintroduce nuts and seeds you should reintroduce a different nut or seed at a time, as not all nuts and seeds are created equally, and some people do fine when eating certain nuts and seeds, but they don’t do well when eating other nuts and seeds.

I also mentioned earlier that you should consider eating soaked and sprouted nuts and seeds, at least until your gut has fully healed.  If you don’t want to do this on your own there are some companies that will do this for you, although they are significantly more expensive than buying regular raw nuts and seeds.  But Nate’s Raw Harvest is one company that sells organic nuts and seeds that are soaked and sprouted.  Wilderness Family Naturals also has organic nuts and seeds that are soaked and dried, although they aren’t sprouted.  It’s also worth mentioning that even if you soak the nuts and seeds and don’t sprout them this will still reduce some of the compounds I’ve discussed in this post and will make them easier to digest.

In summary, while nuts and seeds have some good health benefits, they are excluded from an autoimmune Paleo diet mainly because they are common allergens and they have compounds that can potentially interfere with gut healing.  The same is true with nut milks and nut butters.  However, many people with Graves’ Disease and Hashimoto’s are able to successfully reintroduce nuts and seeds before getting into a state of remission, although not everyone.  In addition, soaking and sprouting them will make them much easier to digest, and so this is something to consider doing.