What are lectins?
Lectins in plants are a line of defence against microorganisms, pests, and insects; a defence mechanism 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.
Lectins are a type of protein that can bind to cell membranes by attaching to a sugar anchor and offer a way for molecules to stick together without getting the immune system involved, which can influence cell-to-cell interaction.
Lectins are abundant in raw legumes and grains, and most commonly found in the part of the seed that becomes the leaves when the plant sprouts, but also on the seed coat (bran). They’re also found in dairy products and certain vegetables. While lectin content in food is fairly constant, the genetic altering of plants has created some fluctuations. Plus, we eat a lot more grains than we are supposed to. Our western diet is actually based on grain and grain-products, and are often highly processed and in many different ways.
Lectins are thought to play a role in immune function, cell growth, cell death, and body fat regulation.
Because we cannot digest lectins, we often produce antibodies to them.
Almost everyone has antibodies to some dietary lectins in their body.
This means responses vary between individuals, and can create intolerances or give the same symptoms as gluten-intolerance or lactose-intolerance for example.
There are some lectins that no one should consume.
Red Kidney Beans, for example, should never be made to sprout. This is due to their of phyto-haemagglutinin – a lectin that can cause red kidney bean poisoning.
The poisoning is usually caused by ingesting raw, soaked kidney beans. Just a few beans can trigger symptoms – raw Kidney Beans contain from 20,000–70,000 molecules (Lectins), while fully-cooked beans usually contain a lot less, about 200–400.
While many types of lectins cause negative reactions in the body, there are also health promoting lectins that can decrease incidence of certain diseases. The body also uses lectins to achieve many basic functions, including cell to cell adherence, inflammatory modulation and programmed cell death.
As previously explained, Lectins can cause damage to the gut wall by attaching to a sugar anchor, present on the cell membrane itself. Although, it causes very minor damage to the lining of the GI tract, and it is normally repaired very quickly, since the purpose of the gut lining is to let the good stuff past and keep the bad stuff contained, it’s important for the cellular repair system to be running at full efficiency.
Sometimes, Lectins can impact on gut wall repair and overwhelmed cells cannot regenerate as fast as they need to in order to keep the intestinal lining secure, compromising gut's integrity, a leading cause of “leaky gut”. Larger molecules can therefore enter the blood stream and cause havoc – a much broader immune system response as the body’s defences move in to attack the invaders. Symptoms can include acne and skin rashes, joint pain, and systemic inflammation.
When someone suffers from Crohn’s disease or irritable bowel syndrome, the gut lining seems to be more sensitive to food lectins. This might be due to the high turnover of cells and greater presence of immature cells.
Unrefined grains are more nutritious than refined versions because they contain more nutrients. However, they also provide more lectins (and other anti-nutrients. e.g. Phytates).
While this was likely never a problem when we grew and harvested our own grains, we now have access to MANY whole grain products. Before the invention of modern agriculture, grains were a minor and seasonal crop. Now we can go to the supermarket leave with a cart full of pasta, bread, rice, quinoa, kamut, amaranth, oats, barley, etc.
Soaking, fermenting, sprouting and cooking will decrease lectins and free up the good nutrients.
Soaking beans and legumes overnight; changing the water often; adding sodium bicarbonate to water may help neutralise Lectins further; as draining and rinsing again before cooking. Fermentation allows beneficial bacteria to digest and convert many of the harmful substances (sourdough bread or beer, is still considered as fermented grains).
Cooking with seaweed can help reduce the Lectin and Phytate content, especially when cooking Beans and Legumes, as seaweed can attract and capture them and be evacuated via the natural elimination channels
The “Blood Type Diet” is based on how our blood cells react with lectins in foods.
Some experts hypothesise that it is of no coincidence that the top eight allergens also contain some of the highest amounts of lectins (including: dairy, egg, wheat, soy, peanuts, tree nuts, fish, shellfish).
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