OPPOSES.

Risk characterization for the "healthy" general population

What does the Federal Institute for Risk Assessment (BfR) say?

The (German) Federal Institute for Risk Assessment (BfR) is a scientifically independent institution within the remit of the Federal Ministry of Food and Agriculture (BMEL). It advises the federal government and the federal states on issues of food, chemical and product safety. The BfR conducts its own research on topics that are closely related to its assessment tasks.

At the beginning of 2024, the BfR wrote a statement or assessment on the topic of lectins. The original article is publicly available for download:
https://www.bfr.bund.de/cm/343/lektine-in-pflanzenbasierten-lebensmitteln-gibt-es-ein-gesundheitliches-risiko.pdf

The BfR concludes that lectins pose only a low risk to healthy people. I take a similar view and would like to go into a few of the BfR's statements in more detail below. These can all be found in the original article in section 3.

[....] As sugar snap peas and peas only contain a small amount of lectins, they are exempt from this preparation recommendation and, according to the German Nutrition Society (DGE), can also be eaten raw in small quantities (DGE, 2016; BZfE, 2020). This also applies to many other lectin-containing foods such as tomatoes, mushrooms and bananas. If consumed in moderation, most lectins are not expected to be harmful to human health[....].

In contrast to the popular opinion that you should eat lots of tomatoes, for example, the BfR sounds much more restrictive here and at least drastically limits the recommended quantities.

[....] Lectins are glycoproteins that occur in various plant-based foods. Depending on the quantity and the specific lectin, they can damage the microvilli (protrusions) of the intestinal mucosa and disrupt the absorption of nutrients as well as cause clumping of the red blood cells.
[....]
The fact that most people have no lectin-related damage to the intestinal tract, even though they regularly consume lectins with their food, could be due to the low intake levels, the protective layer of the intestinal epithelium consisting of carbohydrate-protein compounds (glycoconjugates) and the ratio of intestinal surface area to the amount of lectins from food[....]

This is a very good explanation why lectins have no immunological relevance for some people.

[....] In view of the possible toxic and sometimes allergenic (see 3.3) potential of lectins in combination with the expected increase in plant-based diets, the further development of analytical methods that can easily and efficiently detect lectins in food would be fundamentally desirable [....].

In my opinion, it makes a lot of sense to think about the (negative) consequences of a dietary recommendation to consume more plants.

[....] In addition to their possible toxic properties, some lectins also appear to have allergenic potential (Barre et al., 2020). For example, lectins in the following six foods are classified as potential food allergens by the WHO/IUIS (World Health Organization/International Union of Immunological Societies) Subcommittee on Allergen Nomenclature (allergen and associated lectin in brackets): Banana (Mus a 2, class I chitinase), wheat (Tri a 18, wheat germ agglutinin), maize (Zea m 8, class IV chitinase), beet (Bra r 2, chitin-binding protein), chestnut (Cas s 5, chitinase) and avocado (Pers a 1, class I chitinase) (Pomés et al., 2018). The underlying mechanisms of action, the exact extent of the possible allergenic potential and clarification of whether other lectins from other types of fruit and vegetables are also potential food allergens requires further scientific investigation.[....]