The Science Of Lectins—The Good, The Bad And The Ugly

Plant-Based Diet
Plant-Based Diet
Plant-Based Diet
Plant-Based Diet

For all of those who are late to the party, there is a continuing debate over lectins, what they are and how they work. We will be in the pursuit of shedding some light on what these are, and what purpose they serve.

What Are Lectins? What Is Their Function In Your Body?

Lectins come from the Latin word legere, meaning “to select”and are found in various amounts in animal and plant-based foods. These are structures that are made up of carbohydrate binding sites, which in turn are made up of amino acids. The binding sites of lectins have different properties based on the amino acids present. There are some lectins that contain glycoproteins attached to their structure (sugar containing substances).

Now we slowly make our move away from the dry chemistry lesson.

In the plant kingdom, there are many types of lectins, and these include:

  • Cucurbitaceae lectins in the juice of cucumbers, melons, and squashes
  • Hemagglutinin and Agglutinin, which are primarily present in beans and grains
  • Prolamins present in grains
  • Legume lectins in beans and lentils

Lectins are present in animal-based foods with the highest concentration appearing in dairy products.

The controversy surrounding lectins seem to be focussed squarely on plant lectins and the conflicting opinions that are being put across from various strata of science and medicine. The science is still yet to fully learn all it has to learn about these proteins, which are present in our plant-based meals.

Collectively lectins are responsible for the following functions:

  • Cellular mitosis
  • Host defense
  • Physiological regulation
  • Cell communication
  • Carbohydrates storage
  • Sugar transport

Lectins: The Carbs That Help To Bind Protein

Their structure lets lectin bind to carbohydrates preferentially. The proteins are categorized based on the types of carbohydrates they interact with. The specificity of the binding affects the type of actions that are provided by different categories of lectin.

It has been studied that lectins help to facilitate the communication between cells by means of creating links between carbohydrates on cellular structures and making adjustments in the responses. Some of the viruses and bacteria benefit from the binding action of lectins. Carbohydrate’s bonding is weak and is easily reversible, though.

Where Are Lectins Most Abundantly Found?

Lectins are present in vegetables that belong to the nightshade family. Within these, some of the major sources of lectin include the likes of:

  • Peanuts
  • Soybeans
  • Red kidney beans
  • Tomatoes
  • Corn
  • Wheat
  • Squash
  • Potatoes

Most of these foods are staples in whole, plant-based diets but these are being deemed dangerous by those following the lectin-free diet narrative.

Lectins Help In Building Plant Defence

Research on plants shows that upon damage, there is a stimulation of increase in lectin production, and it goes to suggest that lectin production plays a key role in the immune system of the plants. The ability of lectins to facilitate signaling between cells may be beneficial when the plants need to have their defenses ready when they are against disease, predators and other attacks. The binding property of lectins may be what is creating toxicity to pests and pathogens and making it difficult for them to take up nutrients or synthesize essential portions.

Can Lectins Reduce Swelling And Inflammation?

The crux of the debate is whether the role of lectins is detrimental or beneficial. One particular group of lectins called selectins help the immune cells such as leukocytes to bind to injury sites in the body and allow the attachment and movement of these cells along with damaged tissue.

Different sorts of injuries have been known to stimulate the release of different types of selectins that help in performing specific healing tasks.

Disease Fighting And Coagulation Properties Of Lectins

Agglutinin and hemagglutinin and are 2 types of glycoprotein lectins with the function of promoting clumping of cells. Hemagglutinin stimulates the coagulation of blood cells, and prevents further blood loss. The lectins play a key role in the platelet binding when the clots are formed or aids in the unification of immune compounds in the need of an immune response.

There are certain properties of lectins that provide therapeutic benefits, for certain diseases that are associated with malignant cells. The binding properties of lectin help in promoting apoptosis or cell death in corrupted and diseased cells, with little to no effect on the surrounding healthy cells.

Do these properties of lectins make it an ally or an enemy for our body?

There are studies that show that consuming lectins can help in strengthening the body in a variety of ways. The research is still only trudging along and it is up in the air, on how much longer it may take to get conclusive evidence on the benefits or adverse effects of lectins…