Do We Dare to Eat Lectins?

Do We Dare to Eat Lectins?

In The Love Song of J. Alfred Prufrock, T.S. Eliot’s protagonist asks, chewing on mortality and the pangs of senescence, if he dares to eat a peach. We can all thank Dr. Steven Gundry for upping the ante, and asking if any of us dares to eat chickpeas or eggplant; apples or oats; beans or lentils; or for that matter, almost any fruit, many vegetables, and most beans, legumes, grains, and certain nuts. His answer is: no. His reason is: lectins.

What are lectins? I am tempted to suggest to all Harry Potter fans that they are to us muggles what Nargles are to witches and wizards: an enigmatic if not imaginary threat in unexpected places, of concern only to the eccentric.

But I suppose a bit more explanation is in order. Lectins are a family of proteins found in many plants, dairy, yeast, eggs, and seafood that can bind to other molecules, notably sugar and carbohydrate molecules, that are present both in foods, and in the membranes of our cells. The case made in The Plant Paradox is that the binding of lectins from plant foods to our cells is a major cause of ill health, and thus we must all fear and avoid lectins, and the rather dire foods- like apples- that sinisterly serve as their delivery vehicles. (For whatever it may be worth to you and Prufrock, peaches happen to be a negligible source.)

This, of course, is utter nonsense.

For starters, the reality of lectins is far more nuanced than the sound bites, scapegoats, and silver bullets of formulaic best sellers in the diet category. The scientific literature raises theoretical concerns about the potential toxicity of lectins in certain contexts, but also suggests the possibility of unique health benefits related to cancer prevention, and gastrointestinal metabolism. Lectins are far more active in binding to our cells when consumed at high concentration and in isolation, as they are in experiments, than when consumed in food- as they generally are by actual humans. Cooking often attenuates the binding action of lectins, or causes them to bind to other compounds in food. 

In that regard, perhaps a new dietary fad predicated on misguided lectin-phobia has one redeeming characteristic: it serves up an argument against another faddish concept, nearly as silly. The fiercest proponents of raw food diets contend, falsely, that raw is always better. While some foods are more nutritious raw, others- like chickpeas, beans, and lentils, to name just a few- are decisively so when cooked. The raw food argument, in other words, is itself overcooked, and the lectin scare perhaps does us the modest service of shining its little light there.

As for all the rest, it is instead propagating shadows of doubt where none are warranted.

This is not the first time we have been warned away from fruits and vegetables, beans and legumes, nuts and grains.  Both low-carb and gluten-free diet advocacy foreswear whole grains, despite overwhelming evidence of the health benefits they consistently confer on all but the constitutionally intolerant. Both low-GI and fructose-is-toxic dietary platforms have caused people, intentionally in the first case and perhaps unintentionally in the second, to abandon fruit, despite overwhelming evidence of its role in defending us even against the very concerns associated with high-glycemic foods and excess fructose, notably type 2 diabetes. We abandoned nuts in the throes of misguided applications of advice to reduce dietary fat intake, somehow reaching the conclusion that Snackwells were good for us, while almonds were not.

This decades-long parade of dietary fads and fashions, an incessant sequence of nutritional misadventures demonstrate one thing above all others: there is more than one way to eat badly, and we the people of the United States seem committed to exploring them all. If you have a new version of dietary nonsense to sell, put it in a book- and we will buy it.

Our history is testimony to the triumph of na?ve nincompoopery over experience, to the conclusion that desperation breeds gullibility. Sorry, I must be in a timorous mood today; next time, I’ll tell you what I really think.

We have been talked into the claim that gluten and wheat are the source of our many ills, despite the salient presence of wheat in the human diet for 15,000 years or so, its nominal role for 100,000 or more; despite the presence of whole wheat in the diets of the world’s most vital and longest-lived populations; and despite a bounty of evidence of every description demonstrating the predominance of benefit. We have been talked into blaming our metabolic misfortunes on all grains, despite an even more compelling body of evidence linking whole grain intake to almost every health benefit imaginable, including marked reductions in the very degenerations of function and cognition for which whole grains have been falsely maligned.

An effort is afoot to talk us into dismissing the liabilities of excess salt consumption on theoretical grounds, even as a massive epidemiologic study looking agnostically at the associations between dietary components and death found salt to top the list. Personally, I don’t think salt, per se, is public nutrition enemy number 1; rather, I think a high concentration of sodium is one of the most consistent indicators of hyper-processed foods that are bad for us in many ways. But that’s a topic for another day.

For now, the new contention that we should avoid all of the most nutritious plant foods, including many vegetables, nearly all fruits, all beans, and all legumes because they contain lectins- takes nutritional nonsense to a whole new level. Following this advice will decimate the quality of your diet, and for anyone who actually sticks with such silliness over time (an unlikely eventuality with any diet)- your health.

The case being made against most of the foods most reliably linked to vitality and longevity suffers from several fallacies common to all manner of nutritional nonsense. One is to prioritize a theoretical concern (or hope) over the prevailing pattern of outcomes among actual people.

Another is the conflation of a change in the dialogue about some threat with a change in the threat itself. In 2015, for instance, the International Agency for Research on Cancer (IARC), a subsidiary of the World Health Organization, declared processed meat- bacon, pepperoni, and such- a class I carcinogen. There was widespread media coverage, the customary hyperbole, and something nearing panic among the “I have never met a slice of bacon I didn’t like” crowd.

But, of course, such a response made no real sense. Yes, processed meat is bad for you, and yes, you’d be better off not eating it. And yes, eating it is rather bad for our fellow creatures and the planet, too.

But the risk from one day to the next changed not at all. Whatever your risk for cancer had been all along, it remained exactly the same the day after the IARC determination was announced. All that had changed was the official position on the matter of that risk. Similarly, the lectins that are in your hummus this week were there last week, too.

The idea that you should renounce many of the foods most decisively and consistently linked to good health outcomes because they contain a compound that can be called a toxin may be the most egregious example of missing the forest for the trees I’ve ever seen, and I’ve spent my career scrutinizing, and repudiating, just that variety of nonsense. For the sake of false promises dangling from one gilded tree, this is a case of burning the forest down.

The answer to- “should you fear lectins now?” is- yes, if and only if you do the same for oxygen. 

As I recently noted to a colleague, oxygen is not a theoretical toxin with theoretical harms in people; it is a known toxic with established harms. The atmosphere of our planet is thus highly analogous to the dietary sources of lectins: both contain compounds with potentially toxic effects, but net benefit is overwhelming both from eating plants, and breathing.

So, do you need to fear lectins now? Dr. Gundry, who reportedly will be happy to sell you supplements to replace the nutrients present in the foods he is telling you not to eat, says: yes.

I say: hold your breath, and count to a thousand while contemplating the theoretical toxicities of oxygen. Long before you finish, the truth will likely come to you in a gasp.

 

-fin

David L. Katz

Director, Yale University Prevention Research Center; Griffin Hospital

Immediate Past-President, American College of Lifestyle Medicine

Senior Medical Advisor, Verywell.com

Founder, The True Health Initiative

Follow at: LinkedIN; Twitter; Facebook

Read at: INfluencer Blog; Huffington Post; US News & World Report; Verywell; Forbes

Wade R. Smith

Thankful to be of service to injured patients.

7 年

Based on this post i researched to a moderate degree the work of Dr. Gundry. As an academic Ortho trauma surgeon with research experience, i found his claims and websites disconcerting. I am sure he believes in what he is selling and saying. However, the data overall seems fairly clear at this point in support of omnivore diets with a preponderance of fresh vegetable, fruits, real while grains, legumes as Dr. Katz describes. No one seems to be prematurely dying due to tomato ingestion. Those proposing a conspiracy theory of scientists, doctors , big food and and government to slant research away from the supposed miracle benefits of eating just meat and vegetables don't really get how science works. None of us agree enough to form a successful conspiracy!

Nalini Deshpande

Accredited Practicing Dietitian (APD) @ Lakeside medical Practice Warilla NSW 2528

7 年

A very appropriately explained evidence of the health risks of fad madness. I agree with every word of this posting. The truth in its humour really hits hard. Dietitians have a harder task on their hands however will they ever get an equally important recognition as that of medical doctors who generally have very little time to spare with their patients to provide the appropriate complete dietary advice. In Australia DAA has come a long way however there is still a longer way to go to reach the goal, if at all we can reach it.Leave your thoughts here…

Marnie Nitschke

Expert gut health dietitian, Founder of Fork That Nutrition

7 年

A great combination of expert knowledge and good old common sense here from David Katz, as usual. Articles like this are so helpful, in helping us navigate the minefield of nutritional information out there, to ensure we advise our clients appropriately.

Rosemary Stanton

Independent Health, Wellness and Fitness Professional

7 年

Thank you David Katz for yet another article pointing out the absurdity of many misconceptions that lead to dietary fads.

Cherish Patterson

Purchasing Manager @ LaVanture Products Co. | BS in Sociology

7 年

I am of the 5% of people who have lost weight and maintained it. 337 pounds, now 165 pounds and have maintained for 10 years. This is what I know about my own path and my success. Health is a personal journey and there will never be a one size fits all answer for health. Diets fail, but changing your lifestyle slowly results in lasting change. Dr. Gundry may not have nailed it with his last book, but not a soul out there ever will. There a far too many variables to each person's map to health, so the more information and opinions that are available for people to read and absorb, the better in my book. Let me explain, I have tried Weight Watchers, low carb, Paleo, Dr. Gundry's Diet Evolution, and a host of other ways to health and not a single one of them is something I practice in whole. But, being part of that 5% I know this truth for myself. My health is a compilation of every article, book and plan I have ever read then tested, tried and implemented into my daily routine. It is a veritable menagerie of different thoughts and ideas that have come together to hold hands and walk with me on my path to health. Fear not the ideas that seem out in left field, or dangerous, fear the people not willing to try anything and ever falling down the spiral to obesity and sickness. Agree or disagree with someone's stance on health, but in my own opinion, anything that could spark a persons desire towards health is a fellow health warrior in the battle to help save lives.

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