lectin rich foods • what you need to know

With the release of Dr. Steven Gundry’s latest book, The Plant Paradox, [and now his newest book, The Longevity Paradox] a new “villain” has emerged on the food scene. Enter, the LECTIN.

WHAT ARE LECTINS?

Lectins are nothing new. They are a type of protein found in the foods we eat. It is thought that lectins evolved as part of a plant’s natural defense system, helping to discourage animals from eating them. However, lectins aren’t just limited to plants since we find them in animal products as well. In your body, lectins can bind to specific sugar molecules located in our nerves, gut lining and our blood which Dr. Gundry claims causes them to interfere with the ability of our immune system to communicate with cells, wreaking havoc on our health.

Lectins in plants are a defense against microorganisms, pests, and insects. But may also have evolved as a way for seeds to remain intact as they passed through animals’ digestive systems, for later dispersal. Lectins are resistant to human digestion and they enter the blood unchanged.

Foods that are high in lectins include grains, beans, legumes including corn, soy and peanuts, wheat, potatoes, and tomatoes. They are also found in dairy products and other seeded vegetables.

While Dr. Gundry has the propensity to make polarizing statements [and push quite a few products along the way] he has quite a bit of street cred and some science to back up his claims.

HERE’S WHAT YOU NEED TO KNOW ABOUT LECTINS…

Ingesting lectins poses a “challenge” to your digestion and your immune system.

  • Lectins and your digestion: This GI distress happens because lectins can damage the intestinal lining. As lectin rich food passes through the gut, it causes very minor damage to the lining of the GI tract. Normally, the cells repair the damage quickly. However, lectins have the capacity to blunt this speedy reconstruction. Our cells can’t regenerate as fast as they need to in order to keep the intestinal lining secure. Thus, our natural gut defenses are compromised after the damage occurs and over time the gut can become “leaky,” allowing various molecules [including “invaders”] to pass back and forth amid the gut wall. We may also not absorb other important things, such as vitamins and minerals, properly. When enough lectins are consumed, it can signal our body to evacuate the GI’s contents. This means cramping or urgency while exercising or worse… chronic diarrhea. Unfortunately, this will feel confusing to your body since the more plants you eat [lectin-rich of course] the worse your symptoms appear.
  • Lectins and the immune system: When lectins negatively impact the gut wall, it may also cause a broader immune system response since the body’s defenses move in to attack the invaders. Symptoms can include skin rashes, joint pain, and general inflammation. Here’s the good news: the effects of dietary lectins only extend for as long as they are in the body, and the effects can be reduced by eating a variety of fruits, vegetables in moderate amounts as well as by ingesting foods with beneficial bacteria [i.e fermented foods].

A SUBTLE WARNING

While I remain cautious around using the word “never” with food, there are some lectins that no one should ever consume. Ricin, a lectin from the castor oil plant is so toxic, it can actually kill you! Same with phytohaemagglutinin – a lectin in sprouted red kidney beans The poisoning is usually caused by the ingestion of raw, soaked kidney beans. As few as four or five raw beans can trigger symptoms. Raw kidney beans contain from 20,000 to 70,000 lectin units, while fully cooked beans usually contain between 200 and 400 units.

SO WHAT’S THE SOLUTION? HOW CAN WE NEUTRALIZE LECTINS?

It begins with preparation mechanisms. By sprouting, soaking, cooking and or fermenting lectin-rich foods [with the exception to kidney beans and castor oil] you can deactivate or decrease lectin content.

  • Sprouting- Generally, the longer the duration of sprouting, the more lectins are deactivated. The lectins in some grains and beans are in the seed coat. As it germinates, the coat is metabolized – eliminating lectins.
  • Soaking and cooking- Soak beans and legumes overnight, and change the water often. Drain and rinse again before cooking. Adding a tiny splash of apple cider vinegar to the soaking water may help neutralize the lectins further.
  • Fermenting- Fermentation allows beneficial bacteria to digest and convert many of the harmful substances. No wonder some of the healthiest populations adhere to fermented soy products like miso, tempeh, tamari and natto. Cultures with a history of grain eating traditionally have used some form of fermentation to treat grains. If you’ve had sourdough bread or beer, you’ve had fermented grains.

THE TAKEAWAY

So clearly we should avoid all lectins like the plague, right? Well Dr. Gundry would answer that with a resounding YES; however, I’m not so sure. Lectins can be neutralized by how you prepare these foods prior to eating. It’s why you can’t eat raw kidney beans, but they’re just fine cooked.

My sage advice is this… invest the time into sprouting, soaking, cooking and fermenting lectin-rich foods. Your great grandmother would be proud. And you just might find some of those sneaky symptoms of digestive distress loosen their grip on you.

Since lectins are so widely distributed in foods commonly consumed [many of which are vegetables] and have have been safely consumed for centuries, there is no reason to remain “fearful” around these foods. Instead take note of which foods contain more lectins than others and do the work necessary to allow your body access to the nutrients within. After all food is just “information” to the body. And by decreasing lectins you increase your body’s utilization of food’s message.

  • Alexendra Rowles. (2017, April 28). 6 Foods That Are High in Lectins. Retrieved from http://www.healthline.com/nutrition/foods-high-in-lectins
  • Gundry, S. (2017). The Plant Paradox. New York, NY: HarperCollins.
  • Gundry, S. (2017, May 23). 15 Ways to Reduce Lectins in Your Diet. Retrieved from http://gundrymd.com/reduce-lectins-diet/
  • Deshpande SS. Handbook of Food Toxicology. 2002.
  • Imir T & Bankhurst AD. Inhibition of Natural Killer and interleukin 2-activated NF cell cytotoxicity by monosaccharides and lectins. Mikrobiyol Bul 1987;21:245-250.
  • Chamaillard L, et al. Polyamine deprivation stimulates natural killer cell activity in cancerous mice. Anticancer Res 1993;13:1027-1033.
  • Luk GD, et al. Biochemical markers in colorectal cancer: diagnostic and therapeutic implications. Gastroenterol Clin North AM 1988;17:931-940.
  • Erickson RH, et al. Effect of lectins on the activity of brush border membrane-bound enzymes of rat small intestine. J Pediatr Gastroenterol Nutr 1985;4:984-991.
  • Grant G. Anti-nutritive effects of soybean: a review. J Anim Sci. 1982;55:1087-1098.
  • Watzl B, et al. Dietary wheat germ agglutinin modulates ovalbumin-induced immune responses in Brown Norway rats. Br J Nutr 2001;85:483-490.
  • Falth-Magnusson K., et al. Elevated levels of serum antibodies to the lectin wheat germ agglutinin in celiac children lend support to the gluten-lectin theory of celiac disease. Pediatr Allergy Immunol 1995;6:98-102.
  • Hollander D, et al. Increased intestinal permeability in patients with Crohn’s disease and their relatives. A possible etiologic factor. Ann Intern Med 1986;105:883-885.
  • Pusztai A. Dietary lectins are metabolic signals for the gut and modulate immune and hormonal functions. Eur J Clin Nutr 1993;47:691-699
  • Pusztai A, et al. Antinutritive effects of wheat germ agglutinin and other N-acetylglucosamine-specific lectins. Br J Nutr 1993;70:313-321.
  • Hoss VK, Raabe G, Muller P. Lectin arthritis: a new arthritis model. Allerg Immunol (Leipz) 1976;22:311-316
  • Braun J & Sieper J. Rheumatologic manifestations of gastrointestinal disorders. Curr Opin Rheumatol 1999;11:68-74.
  • Cordain L, et al. Modulation of immune function by dietary lectins in rheumatoid arthritis. Br J Nutr 2000;83:207-217.
  • Livingston JN & Purvis BJ. Effects of wheat germ agglutinin on insulin binding and insulin sensitivity of fat cells. Am J Physiol 1980;238:E267-E275.
  • Freed DJ. Dietary Lectins in Food Allergy and Intolerance. Brostoff and Callacombe Editors Bailliere Tindale Publishers, London.
  • Shemer J & LeRoith D. The interaction of brain insulin receptors with wheat germ agglutinin. Neuropeptides 1987;9:1-8.
  • Ponzio G, et al. Wheat germ agglutinin mimics metabolic effects of insulin without increasing receptor autophosphorylation. Cell Signal 1990;2:377-386.
  • Shechter Y. Bound lectins that mimic insulin produce persistent insulin-like activities. Endocriology 1983;113:1921-1926.
  • Kitano N, et al. Detection of antibodies against wheat germ agglutinin bound glycoproteins on the islet-cell membrane. Diabet Med 1988;5:139-144.
  • Hokama A, et al. Roles of galectins in inflammatory bowel disease. World J Gastroenterol 2008;14:5133-5137.
  • Rabinovich GA & Toscano MA. Nat Rev Immunol 2009;9:338-352.
    How Lectin In Undercooked Red Beans And Rice Causes Food Poisoning
  • Hamid R & Masood A. Dietary lectins as disease causing toxicants. Pakistan Journal of Nutrition 2009;3:293-303.
  • Messina JL, et al. Insulin-mimetic actions of wheat germ agglutinin and concanavalin A on specific mRNA levels. Arch Biochem Biophys 1987;254:110-115.
  • Jordinson, M, et al. Soybean lectin stimulates pancreatic exocrine secretion via CCK-A receptors in rats. Am J Physiol 1996;270(4 Pt I):G653-G659.
  • Rudiger H, et al. Medicinal chemistry based on the sugar code: fundamentals of lectinology and experimental strategies with lectins as targets. Curr Med Chem 2000;7:389-416.
  • Mondoa EI & Kitei M. Sugars the heal.
  • Pierini C. Lectins: Their damaging role in intestinal health, rheumatoid arthritis and weight loss.
    Plant Lectins
  • Sharon N. Lectins: Carbohydrate-specific Reagents and Biological Recognition Molecules J Biol Chem 2007;282:2753-2764.
  • Hernandez JD & Baum LG. Ah, sweet mystery of death! Galectins and control of cell fat. Glycobiology 2002;12:127R-136R.
  • Ibrahim, SS. Effect of soaking, germination, cooking and fermentation on antinutritional factors in cowpeas. Nahrung/Food. 2002; 46(2):92-95.

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