How Mood and Gut Health Are Linked » The Paleo Mom

How Mood and Gut Health Are Linked » The Paleo Mom

February 11, 2012 in Categories: Beyond Paleo, Gut Health by ThePaleoMom
 

One of the challenges that I face personally with my health is something called the Gut-Brain Connection (or sometimes called the Gut-Brain Axis).  Basically, brain health affects gut health affects brain health affects gut health.  It’s an idea that has been around in the scientific literature for decades (at least seven of them!), but has yet to pervade medical practice (like so many nutrition-related health issues).  I have been really interested in this topic for a while now and I thought it was time that I shared some of this information with you.  I know this is A LOT of information, so please feel free to comment with any questions (or skip to the salient points , which are italicized or bolded).

The entire gut is lined by an extensive network of neurons embedded directly into the walls of our esophagus, stomach, intestines, rectum and colon.  This is called the enteric nervous system, which consists of more neurons than in either the spinal cord or the peripheral nervous system.  This network of neurons is so extensive, that it has been coined the “Second Brain”.  It has the very important job regulating all the various aspects of digestion, from breaking down food, to absorbing nutrients, to expelling waste.

It may not be surprising that the brain has a direct effect on the digestive system.  For example, thinking about food can release digestive enzymes into the stomach before you even eat.  If you’re nervous or stressed, your stomach may feel upset.  But how does this work?

•  Your brain sends signals to all of the nerves in your body.  These signals are essential for everything from breathing to moving your legs so you can walk.  A very large portion of your brain’s output is directed into the vagus nerve, the nerve which innervates (which means branches into the nerves controlling) most of the thoracic (chest) and abdominal cavities.  The vagus nerve thus controls a wide variety of functions, from your heart beating, to the secretion of digestive enzymes, to the peristalsis of your intestines.  The important part here though, is that the vagus nerve innervates the digestive tract. 

• Stress, anxiety, depression and strong negative emotions decrease your brain activity, which decreases activation of the vagus nerve.  This will reduce pancreatic enzyme secretion and cause poor gallbladder function, thereby reducing stomach acid production, as well as decrease gut motility, decrease intestinal blood flow, and suppress the intestinal immune system.  

• When this reduced vagus nerve activation is persistent, the slowing down of so many digestive functions results in something called Small Intestinal Bacterial Overgrowth (SIBO), an increased growth of pathogenic yeast and bacteria in the gut (specifically the small intestine, the longest section of our intestine responsible for nearly all digestion).  These are not the beneficial bacteria that we are supposed to have lower down in our digestive tract.

• These “bad” yeast and bacteria (which are also too high up) contribute to an increase in intestinal permeability (a.k.a. leaky gut) beyond what is already caused by the lectins and saponins in dietary grains and legumes.  Even in the absence of dietary grains and legumes, SIBO can cause a sufficiently leaky gut to produce systemic, chronic low grade inflammation.  This effect of the brain on the gut is why people who suffer depression so often also have constipation or suffer from Irritable Bowel Syndrome.

I know this is dense, but the basic point is that stress, anxiety and depression result in a leaky gut.
What you might not already know is that the gut has a direct effect on the brain.  A troubled intestine can send signals to the brain, just as a troubled brain can send signals to the gut.

• Actually, about 90 percent of the fibers in the vagus nerve carry information from the gut to the brain and not the other way around.  There is scientific evidence to suggest that the gut can communicate directly with the brain, perhaps having a direct impact on emotions and moods via the nervous system.

• Better understood though, are the chemical signals that are sent to the brain from the irritated/damaged gut.  When the gut becomes leaky and inflamed, the inflammatory cytokines (chemical signals of inflammation) that are produced in the gut travel through the blood to the brain. 

• These inflammatory cytokines cross the blood-brain barrier and activate the resident immune cells of your brain, the microglial cells.  Yes, this is exactly what it sounds like: a leaky gut causes body-wide inflammation, including inflammation in the brain.

Now, for the vicious circle part:  an inflamed brain has decreased nerve conductance which manifests as stress, depression and/or anxiety.

This is the Gut-Brain Connection.  Stress, depression and anxiety lead to Small Intestinal Bacterial Overgrowth which leads to increased inflammation including inflammation in the brain which leads to stress, depression and anxiety.  Which comes first?  It’s probably different in different people, depending on your own physiology, diet and life circumstances.  Truthfully, once you are in the vicious cycle, it doesn’t really matter what started it.

 

What can you do about it?  I will delve deeper into healing the gut (and healing the brain) in future posts. See my posts about Repairing the Gut and also

What Should You Eat To Heal a Leaky Gut? for more information.

 

These are the major points: manage stress, sleep well, and eat a paleo diet that also includes bone broths and fermented foods like kefir (you can make your own coconut milk kefir if you can’t tolerate any dairy), homemade sauerkraut (see my review of the book Fermented, a great resource for how to ferment foods at home), and kombucha tea.

 

For more information, I recommend checking out Chris Kresser’s blog: www.chriskresser.com

Lectins in grains and legumes - Dr. K News: Autoimmune diet

Dr. K News: Autoimmune diet

Lectins in grains and legumes

Grains and legumes are also high in lectins. Lectins have been shown to degrade the intestinal barrier. Once in the bloodstream they may bind to insulin receptors and leptin receptors (leptin acts in concert with insulin to control appetite). Some believe lectins may also have the ability to desensitize these receptors, thus contributing to insulin resistance and leptin resistance.

Why Grains Are Unhealthy | Mark's Daily Apple

Why Grains Are Unhealthy | Mark's Daily Apple

I find that grain bashing makes for a tasty, but ultimately unsatisfying meal.

You all know how much I love doing it, though. But no matter how often I sit down to dine on the stuff (and I’ve done it with great gusto in the past), I always leave the table feeling like I left something behind. Like maybe I wasn’t harsh enough about the danger of gluten, or I failed to really convey just how much I hated lectins. If I didn’t know better, I’d think the mere mention of grains was eliciting a crazy insulin-esque response and throwing my satiety hormones all out of whack. I was filling up on anti-grain talk, but I just couldn’t fill that void for long.

Well, I’ve got the hunger today, and this time I aim to stuff myself to the point of perpetual sickness. I don’t ever want to have to look at another anti-grain argument again (yeah, right). If things get a little disjointed, or if I descend into bullet points and sentence fragments, it’s only because the hunger has taken over and I’ve decided to dispense with the pleasantries in order to lay it all out at once.

So please, bear with me.

Apart from maintaining social conventions in certain situations and obtaining cheap sugar calories, there is absolutely no reason to eat grains. Believe me – I’ve searched far and wide and asked everyone I can for just one good reason to eat cereal grains, but no one can do it. They may have answers, but they just aren’t good enough. For fun, though, let’s see take a look at some of the assertions:

“You need the fiber!”

Okay, for one: no, I don’t. If you’re referring to its oft-touted ability to move things along in the inner sanctum, fiber has some unintended consequences. A few years back, scientists found that high-fiber foods “bang up against the cells lining the gastrointestinal tract, rupturing their outer covering” which “increases the level of lubricating mucus.” Err, that sounds positively awful. Banging and tearing? Rupturing? These are not the words I like to hear. But wait! The study’s authors say, “It’s a good thing.” Fantastic! So when all those sticks and twigs rub up against my fleshy interior and literally rupture my intestinal lining, I’ve got nothing to worry about. It’s all part of the plan, right?

Somehow, I’m not convinced that a massive daily infusion of insoluble grain fiber is all that essential. And that “lubricating mucus” sounds an awful like the mucus people with irritable bowel syndrome complain about. From personal experience I can tell you that once I completed my exodus from grains, the IBS completely stopped. If you’re not yet convinced on the fiber issue I’ll refer you to Konstantin Monastyrsky’s Fiber Menace. Anyway, there’s plenty of fiber in the vegetables and fruit I eat. Which takes me to the next claim:

“You need the vitamins and minerals!”

You got me. I do need vitamins and minerals, like B1 and B2, magnesium and iron, zinc and potassium. But do I need to obtain them by eating a carb-heavy, bulky grain? No, no I don’t. You show me a serving of “healthy whole grains” that can compete – nutrient, vitamin, and mineral-wise – with a Big Ass Salad. What’s that? Can’t do it? Thought so.

“But it forms the foundation of the governmental food pyramid!”

You know, I should have just started the entire post with this one. I could have saved my fingers the trouble of typing and your eyes the trouble of reading. Governmental endorsements are not points in your favor, grain-eater; they are strikes against you. An appeal to authority (unless that “authority” is actually a preponderance of scientific evidence, of course) does not an effective argument make. Conventional Wisdom requires consistent, steady dissection and criticism if it is to be of any value.
There’s a reason grains are first and foremost on the list of foods to avoid when following the Primal Blueprint: they are completely and utterly pointless in the context of a healthy diet. In fact, if your average unhealthy person were to ask for the top three things to avoid in order to get healthy, I would tell them to stop smoking, to stop drinking their calories (as soda or juice), and to stop eating grains. Period. Full stop. They really are that bad.

I’ve mentioned this time and again, but the fundamental problem with grains is that they are a distinctly Neolithic food that the human animal has yet to adapt to consuming. In fact, cereal grains figured prominently in the commencement of the New Stone Age; grains were right there on the forefront of the agricultural revolution. Hell, they were the agricultural revolution – einkorn wheat, emmer, millet, and spelt formed the backbone of Neolithic farming. They could be stored for months at a time, they were easy enough to grow in massive enough quantities to support a burgeoning population, and they promoted the construction of permanent settlements. Oh, and they were easily hoarded, meaning they were probably an early form of currency (and, by extension, a potential source of income inequality). And here’s the kicker: they were harsh, tough things that probably didn’t even taste very good. It also took a ton of work just to make them edible, thanks to their toxic anti-nutrients.

Toxic anti-nutrients? Do tell.

Living things generally do not want to be consumed by other living things. Being digested, for the most part, tends to interrupt survival, procreation, propagation of the species – you know, standard stuff that fauna and flora consider pretty important. To avoid said consumption, living things employ various self defense mechanisms. Rabbits, for example, with their massive ears, considerable fast-twitch muscle fibers, and nasty claws, can usually hear a predator coming, outrun (out-hop?) nearly anything, and (in a pinch) slash a tender belly to shreds. Blue whales are too big to fit into your mouth, while porcupines are walking reverse pincushions. Point is, animals have active defense mechanisms. They run, fight, jump, climb, fly, sting, bite, and even appeal to our emotions (if you’ve ever seen a puppy beg for a treat with sad eyes, you know that isn’t just accidental cuteness) in order to survive. All the while, predators are constantly evolving and generating adaptations.

Plants, though, are passive organisms without the ability to move, think, and react (for the most part). They must employ different tactics to ensure propagation, and they generally have to rely on outside forces to spread their seed. And so various methods are “devised” to dissuade consumption long enough for the seed to get to where it’s going. Nuts have those tough shells, and grains have the toxic anti-nutrients, lectins, gluten, and phytates. (Of course there are some obvious exceptions. Fruits are tasty, nutritious, and delicious so that animals will eat them whole and poop out the seeds, preferably into some fertile soil. The seed stays intact throughout the digestive process; it is indigestible by design. No seed “wants” to be digested, because this would defeat the purpose. They “want” to be swallowed, or borne by the wind, or carried by a bee to the next flower, but they do not want to be digested.)

Some animals are clearly adapted to grain consumption. Birds, rodents, and some insects can deal with the anti-nutrients. Humans, however, cannot. Perhaps if grains represented a significant portion of our ancestral dietary history, things might be a bit different. Some of us can digest dairy, and we’ve got the amylase enzyme present in our saliva to break down starches if need be, but we simply do not have the wiring necessary to mitigate the harmful effects of lectins, gluten, and phytate.

Lectins are bad. They bind to insulin receptors, attack the stomach lining of insects, bind to human intestinal lining, and they seemingly cause leptin resistance. And leptin resistance predicts a “worsening of the features of the metabolic syndrome independently of obesity”. Fun stuff, huh?

Gluten might be even worse. Gluten, found in wheat, rye, and barley, is a composite of the proteins gliadin and glutenin. Around 1% of the population are celiacs, people who are completely and utterly intolerant of any gluten. In celiacs, any gluten in the diet can be disastrous. We’re talking compromised calcium and vitamin D3 levels, hyperparathyroidism, bone defects. Really terrible stuff. And it gets worse: just because you’re not celiac doesn’t mean you aren’t susceptible to the ravages of gluten. As Stephan highlights, one study showed that 29% of asymptomatic (read: not celiac) people nonetheless tested positive for anti-gliadin IgA in their stool. Anti-gliadin IgA is an antibody produced by the gut, and it remains there until it’s dispatched to ward off gliadin – a primary component of gluten. Basically, the only reason anti-gliadin IgA ends up in your stool is because your body sensed an impending threat – gluten. If gluten poses no threat, the anti-gliadin IgA stays in your gut. And to think, most Americans eat this stuff on a daily basis.

Phytates are a problem, too, because they make minerals bio-unavailable (so much for all those healthy vitamins and minerals we need from whole grains!), thus rendering null and void the last, remaining argument for cereal grain consumption.
 
What, then, is the point to all this grain madness? Is there a good reason for anyone (with access to meat, fruit, and vegetables, that is) to rely on cereal grains for a significant portion of their caloric intake?

The answer is unequivocally, undeniably no. We do not need grains to survive, let alone thrive. In fact, they are naturally selected to ward off pests, whether they be insects or hominids. I suggest we take the hint and stop eating them.
And with that, I’m done. I don’t think I could eat another bite.

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The Lowdown On Lectins | Mark's Daily Apple

The Lowdown On Lectins | Mark's Daily Apple

Little known to the public at large. Little understood by the health community. Omnipresent in our conventional food culture. Proven to be at least mildly detrimental for everyone and downright destructive for the more sensitive (and often unsuspecting) among us. We’re talking lectins today: common natural agents on the one hand, cloaked thugs of the anti-nutrient underworld on the other. Our popular health media, if they’ve heard of lectins, certainly never make mention of them. Famous health gurus never deign to speak of them. In short, lectins thrive in the American diet basically unfettered, unscrutinized. Make no mistake, however. They’re a menacing power to be reckoned with. I’ve addressed them on Mark’s Daily Apple in the past (Why Grains Are Unhealthy) and in my book (The Primal Blueprint), but I still get a fair number of emails and forum questions asking for more info. As I always say, let’s break it down….

What Are They?

Before Monsanto, Mother Nature had her own pesticide strategy. (Humans being among the “pests” to be warded off.) In order to avoid being completely decimated by insects, foraging animals and Groks, plant species evolved assorted anti-nutrients that would make said pests regret their gorges with a variety of mostly digestive related ailments. Low grade toxins, in a sense. A workable balance developed between plants that were able to safeguard their species’ survival and the “pest” patrons that were able to benefit from the plants’ nutrition but learned to partake more sensibly from their supply. Given that our primal forefolk foraged widely and ate a surprisingly diverse diet, the system worked.
Lectins are essentially carb-binding proteins universally present in plants (and animals). Just as they protect plant species from Grok-sized predators, lectins also support other immunological functions within plants and animals (against pathogense, parasites, etc.) They also assist in other functions like protein synthesis and delivery in animals. They’re relatively sticky molecules, which makes them effective in binding with their sought after sugars but undesirable for our digestion, in which their binding powers can lead them to attach to the intestinal lining and wreak havoc. (More on this in a minute…)
Given their omnipresence in nature, a certain amount of lectin consumption has always been inevitable. To the benefit of the plants, lectins are also hard to break down. Regular old digestive enzymes only do about half the job. Human ingenuity evolved across traditional cultures to “predigest” lectins through food preparation practices (fermenting, soaking, etc.). In our contemporary dietary culture, however, we too commonly skip these practices yet rely on the highest lectin-containing foods for our primary food sources.

What Foods Contain Them?

The short answer here is basically all plants and animal products (PDF) to varying degrees. Nonetheless, lectins are concentrated more in some sources than others. Foods with the highest lectin activity include: grains of all kinds (especially wheat), legumes (especially soy), nuts, dairy, and nightshade plants (e.g. eggplant, tomatoes, potatoes, peppers, etc.). Add to this list the oils and other derivative products from these food sources. And yet another, lesser known category: GMO food, since lectins are often spliced into modified varieties in order to enhance “natural” pest and fungal resistance.

What Do They Do To The Body?

Let’s go back to the intestine again. (Some field trip, eh?) Lectins’ stickiness allows them to bind with the lining, particularly the villi, of the small intestine. The result? Intestinal damage (with impaired cellular repair potential), cellular death as well as compromised intestinal villi, which means reduced absorption of other nutrients, including minerals and protein. Add to this altered gut flora, which can allow certain harmful bacterial strains like E. coli to run rampant. Furthermore, because the body is now responding full-time to the needs of the injured gut lining, proteins and other resources are redirected from other basic growth and repair processes. Furthermore, lectins have been associated with leptin resistance, a pre-diabetic condition linked to obesity.
Perhaps the most insidious impacts lectins can leave in their wake is this: leaky gut. Leaky gut is a term for the breach in the intestinal lining created by lectins hand in hand with other antinutrients. Once the intestinal breach exists, lectins and other particles (like partially digested food, toxins, etc) can “leak” into the bloodstream.

Once lectins open the door, so to speak, out of the small intestine, they and other fugitive particles are now free to move about the body and bind to any tissue they come across (anything from the thyroid to the pancreas to the kidneys). Of course, the body reacts to these invaders by directing an attack on these particles and the otherwise perfectly healthy tissue they’re attached to. Enter autoimmune mayhem. That’s why lectins are linked with autoimmune disorders like IBS, Crohn’s, colitis, thyroiditis, fibromyalgia, chronic fatigue syndrome, and arthritis. Specific lectins have been associated with particular ailments (like wheat with rheumatoid arthritis), but more research is needed to trace and confirm these connections. What is clear, however, is the potent autoimmune destruction that can result when the intestinal lining experiences this level of damage.

Primal Advice For Limiting Lectins

As mentioned, lectins are literally everywhere. Although it’s impossible to eliminate them altogether, you can significantly reduce your intake.

• Purge the worst offenders. That means grains and soy more than anything, but I’d add other legumes to the list as well. Eliminating the foods that contain the highest lectin activity will slash your overall lectin intake – and impact.

• Cut back on other higher lectin sources. Not everyone wants to nix every dairy or nightshade option. Look at how you can reduce your overall intake of these items while keeping enough to enjoy their flavor and nutrient advantages.

• Gauge your sensitivity. For those of us who are most sensitive to lectins, more dramatic measures might be needed. If you know or believe that you’ve already suffered some serious intestinal damage, you might do well to steer clear of as many high and moderate lectin level foods as possible. That means perhaps forgoing nightshades, dairy, legumes and even nuts and eggs in addition to all grains and processed foods. Reintroduce desired foods back into your diet by “family” (e.g. dairy, etc.) and be mindful of any physiological effects (however minor) that accompany them.

• Take up old traditions like soaking, sprouting and using bacterial fermentation techniques for any moderate/high lectin foods like beans you choose to keep in your diet. Fermentation methods are especially effective, virtually eliminating lectins in one study of lentils. All those kitchen rituals you remember from Grandma? They’re adaptive, essentially pre-digestive techniques practiced by traditional cultures around the globe. Going old school on your favorite nut varieties, for example, cuts those lectin levels dramatically.

• Don’t go wholly raw. Yes, there are legitimate reasons to enjoy raw plants in your diet, but I don’t support the practice as a movement or exclusionary principle for eating. Humans have been cooking for well over a hundred thousand years. Some nutrients are enhanced by heat. Some anti-nutrients (like lectins) are at least partially “disarmed” by it. Cooking methods with a mind toward maximizing overall nutrient value and bioavailability make good Primal sense and can lower your exposure to lectins.

• Diversify! Restrictive diets make us even more susceptible to the downsides of our foods. (Soy formula fed babies being a dramatic example of this principle.) Make Grok proud and forage more widely for your dinner. Research shows that simply rotating primary foods was enough to limit lectin-related damage in rats that were given rounds of soy feed. A healthy, mostly low lectin diet will offer enough balance and protective nutrition to blunt the impact of the occasional moderate level lectin sources.

• Avoid GMOs. Hidden lectin is just one more reason to leave GMO products on the shelf.

• Maintain good overall gut health. Our modern existence sometimes seems like one giant assault against our digestive tracts. Minimize cumulative negative effects and increase positive, protective factors. Eat a healthy diet with Primal doses of probiotics, prebiotics and good fats. Limit stress and the use of medications like aspirin, NSAIDs and antibiotics (as well as secondary exposure through antibiotic-administered livestock). A healthy gut will be better equipped to weather the effects of inevitable but reasonable lectin intake.

Now it’s your turn – for your comments, questions and anecdotes about lectin impact. Let me know your thoughts, and thanks for reading!

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Lectins — A Little Known Trouble Maker

Lectins — A Little Known Trouble Maker

While most of the world seems to be touting the benefits of whole grains these days, a few people are insisting that grains are not as healthy as we think.

One of the reasons grains may be a problem in human nutrition is because they contain lectins, a class of molecules called glycoproteins (molecules that contain a protein and a sugar).

While dietary lectins are known in the scientific and nutritional communities, most lay people and even many medical professionals don’t know about them.

Lectins are involved in food allergies/sensitivities, inflammation and autoimmune disease, just to name a few.  For instance, lectins are linked to celiac disease. Even weight gain and low energy can be linked to lectins.

Whole grains, peanuts, kidney beans, and soybeans are high in lectins. Cow’s milk, nightshade vegetables (like potatoes and tomatoes) and some seafood also contain fairly high amounts of lectin.  In fact, estimates are that about 30% of our foods contain lectins, and about 5% of the lectins we eat will enter our circulation.

Lectins are problematic because they are sticky molecules that can bind to the linings of human tissue, especially intestinal cells.   In so doing, they disable cells in the GI tract, keeping them from repairing and rebuilding.¹ Therefore, lectins can contribute to eroding your intestinal barrier (leaky gut).

Because the lectins also circulate throughout the bloodstream they can bind to any tissue in the body ­— thyroid, pancreas, collagen in joints, etc.² This binding can disrupt the function of that tissue and cause white blood cells to attack the lectin-bound tissue, destroying it. This is an autoimmune response.  The lectins in wheat for example, are specifically known to be involved in rheumatoid arthritis.

But why do only some people react to the lectins in foods while others can eat them with no apparent problems?   There are two answers to this question.  First, many people may be having problems but they just don’t realize it.  For example, autoimmune thyroiditis could be caused by dietary lectins.⁶
As another example, many of our patients who thought they had no food intolerance at all have experienced much improved energy and weight control when they eliminated wheat and dairy.  They didn’t realize until after they eliminated these foods that they were being affected by them.
But certainly many people tolerate these foods — why?

The answer lies in the balance of gut flora and a person’s immune system.  When you have adequate beneficial flora, it serves as a protective barrier against substances that travel through the intestines, including lectins.  But importantly, beneficial flora are needed to keep the production going in the intestines of two lectin-protective substances, mucin and secretory IgA.^3,4

Mucin, like lectin, is a glycoprotein in the mucous lining of the intestines.  When lectins travel through the intestines, they should have mucin to bind to, rather than intestinal cells.  But if mucin is missing, lectins will bind to intestinal cells instead.  Secretory IgA also binds to lectins, preventing them from causing damage.⁵ 

If you have any lectin-related health issues like arthritis, allergies or autoimmune disease, our experience shows it is very helpful to reduce your intake of lectins, especially from wheat.  It’s also very important to balance immunity by working on stress management and gut health.

By taking a good quality probiotic you’ll help stimulate adequate mucin and secretory  IgA production.^3,4 And controlling your stress response will help prevent the over production of IgA and maintain immune balance in the gut to improve your tolerance to lectins.

References

1. Pierini C. Vitamin Research News. Jan 2007. 21(1): 1-4.
2. http://www.sciencedaily.com/releases/2007/08/070801091240.htm.
3. Eur J Clin Nutr. 1993 Oct;47(10):691-9.
4. Deplancke B and  Rex-Gaskins H. AJCN. June 2001. 73(6):1131S-1141S.
5. Buts JP, et al. Digestive Disease and Sciences. Feb 1990. 35(2): 251-56.
6. Cordain L et al. British Journal of Nutrition (2000), 83, 207–217.

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What are Lectins?

What are Lectins?

Sep 17, 2008

Lectins are carbohydrate-binding proteins that are found in most plants, particularly seeds and tubers such as cereal crops, potatoes, and beans (legumes).  Traditionally, they have been used as histology and blood transfusion reagents but lectins may be toxic, inflammatory, resistant to cooking or digestive enzymes, and are found in much of our foods.  So how safe are lectins, really?

What are Lectins and What Damage can they Cause?

Lectins are proteins that do not break down easily, and they are resistant to both stomach acid and digestive enzymes.  Lectins may bind to the wall of the gut and damage the gut lining.  They can cause changes in the function of the gut which may be related to diseases such as colitis, Crohn’s disease, Coeliac-Sprue, and IBS.  Because of the damage that lectins do to the gut, other proteins may be able to cross into the body undigested and cause allergic reactions within the body.
As lectins can cross into the body through a damaged gut wall, they can bind to cell membranes in arteries and vessels, organs, and glands. This binding can create reactions which lead to auto-immune disorders or degenerative diseases.  Different lectins are associated with different diseases.  For example, dairy-based lectins are associated with juvenile onset type one diabetes.
Some other diseases that are thought to be associated with lectins include:

• insulin dependent diabetes
  
• rheumatoid arthritis
  
• IgA nephropathy
  
• peptic ulcers

It can be helpful to think of lectin as a type of protein that contains a key that fits a certain lock. The lock is a specific carbohydrate.  If the lectin has the right key comes into contact with the right lock or carbohydrate, the lock is opened, damaging the cell membrane, and thus damaging the cell.  The lectins, however, can be inactivated by specific carbohydrates known as mono and oligosaccharides, which bind the key and stop it from fitting the lock.  It is best not to rely on these carbohydrates completely, though, as the safest path is to avoid all known toxic lectins.

How Do We Become Sensitive to Lectins?

Lectin sensitivity can occur for a variety of reasons.  For starters, we did not evolve to eat the types of food that contain lectins and so the immune system may not be able to handle it.  A certain form of barrier protection in the body, SIgA barrier protection, may fail, for genetic or environmental reasons.  The body may contract a bacterial or viral infection that damages the cells, making them more prone to lectin antibody reactions.  Another reason is by using non-steroidal anti-inflammatories (NSAIDs) or other drugs which increase gut permeability and allow lectins to enter the body.

What Foods Contain Problematic Lectins?

Lectins are found in foods, and the amount of lectins contained in the food depends on the type of plant, how it was processed, and the species.  The main foods that may contain toxic lectins include:

• grains such as wheat and wheat germ but also quinoa, rice, oats, buckwheat, rye, barley, millet, and corn
  
• legumes
  
• dairy foods
  
• the nightshade family e.g. potato, tomato, eggplant, cucumber and capsicum

It is interesting to note that all of these foods have been found to be involved in or cause food allergies or intolerances.  The lectins in foods may be inactivated by soaking, sprouting, cooking, or fermenting.  Soaking legumes overnight and rinsing them well does seem to remove or inactivate many of the lectins present.  Heating may remove lectins in some foods, but not all.  Be aware, however, that of the stated methods, there is little research to prove that they completely remove lectins from foods.

What Can I Do If I’m Lectin Sensitive or Intolerant?

If you are intolerant to lectin, this means that you are not able to stop lectin from binding to the cells in your body.  The lectins therefore create immune responses that damage the cell to which the lectins are attached and potentially surrounding cells.
An elimination diet will need to be undertaken to find out if you are lectin sensitive.  This is where you remove all suspect food groups from your diet for seven days.  On the eighth day, slowly begin reintroducing the eliminated foods.  It is best to only test one food group at a time.  If you notice anything suspicious, such as changes in energy, appetite, bowel function, mood, sleep, or digestion, there is a good chance that you are sensitive to the food.  Once you have identified the suspect food group, it is just a matter of eliminating it from your diet as much as possible.  After twelve months, you can try re-introducing the food into your diet once more.  If you do not react, it is likely that is an environmental intolerance brought on by infection or medication.  If you do react, however, it is likely that it is a genetic intolerance and you will never be able to safely consume the food.

The Good Side of Lectins

The news is not all bad when it comes to lectins.  There have been studies that show that lectins are able to make abnormal and malignant cells stick together, as well as stop them from functioning.  This has important overtones when it comes to types of cancer.  Soy protein in low concentration has this effect on cancer cells, while leaving normal cells alone in blood types A and AB.  Peanut lectins are shown to fight breast cancer cells in blood types A and AB.
Peanut lectins inhibit cancer cell growth and destroy cancer cells in blood types A and AB.  Soy bean lectins makes cancer cells stick together and also destroys them in blood types A and AB.  Fava bean lectins promote cell differentiation in all blood types. Amaranth lectins inhibit cancer growth in blood types A and AB.  Domestic mushrooms promote cell differentiation in all blood types and jackfruit lectins stick together T antigens in all blood types.

Topic: Nutrition