Should I Follow a Lectin-Free Diet for IBS?
Having IBS can feel like riding a very confusing and emotional rollercoaster – one that often leads people to a place in which they will try anything to just feel better. I know, because I have IBS too – and I’m a medical professional – yet I still get that niggling ‘what if…’ when I see something new, but often sensationalized about IBS.
One of newest diet trends to hit the scene is the “lectin-free” or “low-lectin” diet. With many negative health claims, lectins have been getting a bad reputation in the last couple years. In particular, the anti-lectin community has suggested that cutting out lectins improves digestion, reduces cancer, decreases inflammation, and boosts immunity – how could reading that NOT terrify you? If the answer to our digestive problems incites ‘fear mongering’ I often get my patients to do a ‘gut check.’ It’s super easy to oversimplify a very complex problem, which is what I feel people do when they grasp onto one simple solution, followed by ‘how did we not know this before!’
So, what is real when it comes to these claims? Today we will explore the evidence that exists with respect to lectins and irritable bowel syndrome.
What is a lectin?
To start, let’s review what lectins are. Similar to gluten, a lectin is a small protein unit found in a variety of foods – both animals and plants contain them. They can bind to carbohydrates, and are found in a lot of nutrient-dense foods like legumes, nuts, seeds, whole grains, dairy products, and numerous vegetables and fruit. So if you cut out all those foods – what are you left with? Great question – not much.
Lectins have been deemed problematic because they are not digested and therefore pass through the walls of the gut unchanged. However, just because something is “non-digestible” does not mean it’s harmful! Let’s take a moment to think about another poorly digested substance: fiber – important for fueling your good bacteria, regularity and bowel function! So let’s not jump to conclusions about lectins just yet.
Although lectins in IBS may appear to be well researched at first glance, there are actually very few human studies that have been done on the topic. Instead, most findings have been derived from animal studies as well as in-vitro tests – meaning a test tube. Last I checked, you weren’t a rat, and we know from research, what happens outside the body isn’t necessarily replicable inside the body.
In addition to a lack of evidence, there is also too much variance between studies to give us real-world information about lectins. Many anti-lectin advocates claim that lectins irritate the gut, change our gut microbiota, or limit nutrient absorption at high concentrations.
However, the research hasn’t been done – this is all assumptive. And you know what they say about people that make assumptions. As well, when we cook really high lectin foods (which, guys, we always do – I don’t see anyone around here eating raw kidney beans), lectins break down – meaning we consume minimal amounts of lectins in the diet. However – there is a TON of evidence (which – people are entirely ignoring) that supports that a plant based diet, high in fiber, variety, and focused on plant based proteins IMPROVE gut health, immune function, and gut integrity. Overall, the evidence does not support the fact that lectins result in negative health outcomes in our gut.
When you come across a restrictive diet like this, try looking at the food(s) in their entirety instead of isolating one specific nutrient as the culprit – and consider, when a diet is extremely restrictive – what are the long term risks? And if you feel better on it – is it actually the effect of the lectins? Or something else?
At the end of the day, I like to say, you know your body best. If you are following a lectin-free diet, be open to the possibility that you can reintroduce some of these foods – and that perhaps, including some of them would lead to better digestion and more nutritional adequacy in the long run. We KNOW a restrictive diet compromised your gut microbiota – and many times the implications of these restrictive diets on the gut microbiota and long term health outweigh the benefits.
What we see in our practice is, many times – gut issues are more complicated than dietary changes. Consider working with a team that can help you get to the bottom of your gut issues, while giving you as much food freedom as possible!
- Shim, R. (2017, September 13). Lectin is the “new gluten”: Is a lectin-free diet healthy? [web blog post] Retrieved from: https://www.abbeyskitchen.com
- Van Buul, VJ, & Brouns, FJPH. Health effects of wheat lectins: a review. Journal of Cereal Science. 2014; 59(2):112-117