Here our nutritionist Ed gives the low-down on lectins, casting his expert eye on the various perspectives in the nutritional world 

Lectins are a family of proteins that bind to carbohydrates. Most foods contain lectins but significant amounts are found in beans, followed by grains and plants of the ¨Nightshade¨ family. Broad into the limelight by the 2017 publication of Dr. Gundry’s book ¨The plant paradox¨, and subsequently followed by different lectin-free diet guru’s. The plant paradox describes lectins as the #1 danger in our diet, the source of most, perhaps all human disease. 

Telling people to avoid plant foods such as beans, whole grains & tomatoes, which are some of the healthiest foods on the planet, because they contain lectins, seems like terrible advice, it is. The claims made in ‘The plant paradox’ are not backed up by science. A theoretical concern does nothing to change the fact that people who eat the whole foods in which lectins reside have consistent positive health outcomes. 

Lets have a closer look at these lectins. There are many different types of lectins found in the human diet which all have different effects. The first lectin discovered in the 19th century is called ricin from the castor bean. Ricin is known to be potent homicidal poison purported to be used by the Soviet Union. However, most lectins found in food are not toxic, and even the toxic ones that are present in beans, are completely destroyed by cooking the beans. The lectins present are destroyed faster than the beans become palatable. Cooking pre-soaked beans for 10 minutes gets rid off all the lectins and it will take about an hour of cooking before they become soft and mash-able with a fork.

In plant foods these lectins are found in highest concentrations in the seed part of the plant. This gives the seed the ability to survive digestion and still be a viable seed when excreted.  The lectins in plants bind to carbohydrates which slows down their digestion. This is in many cases a good thing, as it lowers the glycemic index of the food consumed and has a positive effect on the insulin level in your body. This is actually part of the reason why beans and other plant foods are beneficial for weight loss. 

There are several studies suggesting some unique health benefits to lectins. Mushrooms for example, contain a type of lectin that inhibits the growth of cancer cells. These plant poisons in the doses they are present in properly prepared foods are actually beneficial for us. The mid stress of a tiny amount of toxin actually triggers healing responses in our body. Without experiencing these tiny doses of poisons regularly, our immune system become compromised. 

So, it’s true that eating raw kidney beans will make you sick, but the tiny amount of lectins found in properly prepared beans may actually have some benefits, besides all the other health benefits associated with bean consumption. And the same is true for the whole grains and plants of the ¨Nightshade¨ family, which are all bursting with beneficial compounds besides the lectins they contain. 

People with a rare allergy to lectin containing foods and people with digestive issues like IBS or Crohn’s disease should avoid lectin containing foods. But for most of the population, the benefits of eating lectin containing foods like fruits, vegetables and beans, are tremendous, as they come loaded with vitamins, minerals, dietary fibre and other beneficial nutrients.