What are some foods highest in lectins

Lectins: Why everyone is afraid of tomatoes and whole grains now

Instead of unhealthy sausages and ready-made meals, we should rather pack our plates full of fresh vegetables. But the lectins in it are supposed to make you sick. At least that's what a US doctor says. Is it all just scare tactics or is there really something behind it?

What are lectins?

Lectins are proteins or glycoproteins that are found in some plant foods and serve as a defense substance for the plant. Lectins have been known in nutritional science for years, as are their effects on humans. They can be toxic, bind to our intestinal cells and make them more permeable to harmful toxins (leaky gut syndrome). People with weak immune systems are said to be particularly susceptible to it.

That is why lectins harm us

If they get through our body into the blood, they also bind to other cells, e.g. B. our red blood cells, which then clump together and hinder the transport of oxygen and nutrients. Therefore, the lectins are also called anti-nutrients because they have no nutritional value themselves, but can prevent the absorption of other important nutrients. Where they attach themselves in the human organism, they can fuel inflammatory reactions and are therefore also associated with autoimmune diseases such as Crohn's disease, multiple sclerosis or irritable bowel syndrome.

These foods contain lectins

Legumes are among the foods that contain particularly high amounts of lectins. Just a few raw beans can be harmful to the body and cause severe intestinal inflammation in humans or even be fatal. There are also lectins in fresh green beans and should only be eaten cooked. Grains, cashew nuts and peanuts as well as nightshades, e.g. B. Tomatoes, peppers, eggplants and potatoes also contain lectins - all of which are in lower amounts than in legumes. The lectin in wheat is considered to be particularly heat-resistant. Lectins and gluten should not be confused, even if lectins are sometimes referred to as the "new gluten". Overall, whole grains provide a little more lectins than light extract flour, but there are also lectins in baguettes and white bread. The good thing: through the right preparation, we can contain the harmful effects of lectins.

Cooking destroys (most) lectins

Cooking destroys the lectins in legumes and vegetables. When the legumes are soaked in water for a long time, a large part of the lectins is dissolved. The anti-nutrients can also be defused through enzymatic processes, such as when dough rises or when vegetables are fermented. Important for grain: Prepare the dough for as long as possible - as in the old craft tradition and for as long as possible, e.g. B. let go for several hours or overnight. This is often not the case with industrial bread with artificial raising agents. You can find more information and a recipe for "slow" baked bread here.

And tomatoes or cashews that are not eaten heated?

The lectin content is much lower in tomatoes, peanuts and cashews. These amounts do no harm to healthy people and we can therefore eat them without worry. Research is now being carried out into the positive effects of lectins. There is evidence that the proteins can prevent colon cancer. As with much in nutrition, the dose makes the poison. But what is healthy and digestible for some can still lead to complaints for others.

Who better to do without?

If you have a sensitive intestine or suffer from autoimmune diseases, you can try to see whether the symptoms will improve if you stop eating foods containing lectin. It is also best to test whether peppers and tomatoes are better tolerated when cooked and if necessary roast peanuts and cashew nuts in a pan for a few minutes.

Knowledge at a glance

  • Lectins are proteins found in plants that attach to carbohydrate structures in our intestines or in our blood and can thus trigger inflammation.

  • Legumes like lentils and beans, fresh green beans, wheat, cashews, and peanuts, and nightshades like tomatoes and eggplant contain lectins.

  • Most lectins are destroyed by cooking. Exception: the lectin in wheat - agglutinin - is particularly heat-stable.

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