THE LATEST ON LECTINS with Steph Rouillard, @head.over.health
We know that a plant possesses physical barriers – think about spines on a cactus, or the hard-outer shell of nuts – to protect itself from being consumed by animals. However, beyond a plant’s surface, there are ‘sneaky’ groups of natural components – such as lectins,oxalates,phytates, tannins and gluten – that act as chemical defense mechanisms.
Are you on a ‘lectin-free’ diet?
If your answer is YES, then you’re probably misinformed: lectins are extremely pervasive in foods. Of course, there are foods that are higher in lectins such as legumes, whole grains, nightshades (tomatoes, aubergine, sweet peppers and potatoes) but there’s no such thing as a ‘lectin-free’ diet.
Can lectins be harmful?
Yes, very high concentrations of lectins can be harmful, and have been demonstrated to damage the gut lining, compromise nutrient absorption, and impair immune functioning. However, this has only been shown when RAW legumes have been consumed. Up until now, no human studies have demonstrated adverse effects from the consumption of cooked, well-prepared legumes. Soaking, germinating, and fermenting beans have shown to significantly reduce lectin concentrations in plant foods; and in the process, have found that lectins in low doses have surprising potential benefits:
- Lectins may be antimicrobial
Lectins may act to protect us by binding to carbohydrates on the surface of harmful microbes in order to weaken the integrity of the bacterial or fungal cell wall, and prevent the pathogen from binding to your cells.
- Lectins may boost immune activity
Plant lectins have been observed to increase our immune response by increasing the activity of phagocytic cells (immune cells which ‘in digest’ harmful pathogens).
- Lectins may improve blood sugar regulation
Note: up until now, only animal and cell studies have demonstrated the potential for lectins to assist with blood sugar regulation. Let’s watch this space!
- Lectins may stimulate digestive function
Lectins have been shown to stimulate the release of a hormone (cholecystokinin) in the gut, which signals for the release of ‘digestive aids’ (enzymes and bile) needed to break down our foods & enhances gut motility.
Ok, but I do experience adverse effects in response to lectins. How do you explain this?
It’s true that some people do ‘feel better’ when eliminating high-lectin containing foods. However, these are all anecdotal reports: meaning, that no large studies can yet prove this association, and all observations are based on personal accounts. Possible explanations include 1) lectin-containing foods are generally high in fiber, and some individuals with dysbiosis (an ‘unfavorable’ gut microbe balance) don’t tend to tolerate high prebiotic foods and 2) although a rarer possibility, some individuals with autoimmune diseases may generate antibodies (immune complexes) to lectins which may worsen symptoms.
So what’s the take home message:
For most individuals, the scientific to date evidence indicates that lectin-containing foods are beneficial for health as they are predominantly found in plant-based foods which are high in vitamins, minerals, phytonutrients and fiber.
Remember, nutritional advice should always be individualized. Chat to your Dietitian Nutritionist for personalized advice.