Lectins - What Are They? Love Them or Leave Them?
We’re all familiar
with that schoolyard rhyme: “beans, beans, they’re good for your heart….” As
adults we roll our eyes, but have you ever wondered where the rest of that
rhyme came from, or why foods like legumes are so tough to digest?
Turns out that most of our foods contain certain compounds that, by nature, are
difficult on our digestive systems - because they’re not really meant for our
digestive systems. Now, that doesn’t mean we can’t tolerate them but more and
more research is helping us learn the reasons why some foods can be tough on
our systems, and what the implications are of consuming them. In the case of
beans and legumes, amongst other foods, the main culprit we’re learning more
about is lectins.
Lectins are a kind of protein that’s found in a variety of plant- and
animal-based foods. In fact, almost all plant and animal substances contain
them in small amounts.
We know proteins are the building blocks of muscles and are critical to our
health so the question for most of us is: if lectins are just proteins, how
could they be bad for us?
Simply put, lectins bind cells together, and in particular, they bind to
sugars. Their ability to lessen the body’s ability to properly absorb nutrients
puts lectins in a special category known as ‘antinutrients’. Because we can’t
digest lectins, they tend to pass through our systems unnoticed which, for most
people, means antinutrients like lectins don’t pose much of a problem. In fact,
in small amounts, lectins can have numerous health benefits. They’ve been shown
to have an important role in immune function, cell growth, and might even be
helpful in cancer therapy.
However, lectins can wreak havoc for people who consume a diet with lots of
high lectin foods and for those who suffer from GI disorders or immune
deficiencies. In more severe instances where GI disorders and immunity
dysfunction are at play, lectins can have quite a serious effect on the gut
lining and tight junctions that keep the intestines functioning well.
If they’re not meant to be digested, what purpose do
lectins serve?
Lectins have a distinct and important purpose in nature - it’s just that the
purpose is for the organism’s survival, and not for human consumption! The
most important function lectins have in the plant world is to act as a
natural insecticide, protecting plants, grains, and legumes from natural
predators. And they’re great at it too! When predatory insects come in
contact with them, the lectins completely disrupt insect metabolism,
preventing invasions and attacks on the plants. Part of a plant’s defense
mechanisms, lectins are a natural way to strengthen crops against common
pests!
To update that
schoolyard rhyme: the more lectins you consume the more discomfort, nausea,
vomiting, diarrhea, flatulence, and importantly, malabsorption of nutrients you
might experience.
If these sound like familiar symptoms, that could be because the 30% of foods
that have high levels of lectins are ones we commonly eat such as dairy,
nightshades (like tomatoes and peppers), whole grains, seeds, GMO foods, and
yes - beans and legumes.
Some experts have suggested that removing all lectins from your diet can help
the gut to recover from antinutrient-caused distress and that this could be
critical to treating GI and immunity disorders. Still, many others have pointed
to the various preparation techniques that people have used around the globe to
help weaken and eliminate lectin proteins, making these staple foods much
easier to enjoy!
We caution against removing whole categories of foods unless truly necessary,
especially because foods high in lectins also have other essential benefits
such as fibre and minerals, that our bodies need. Instead, we want to provide
you with a variety of methods you can use to prepare high lectins foods that
are centuries old, and globally trusted to make these foods easier to digest.
These are our favourite four ways of
preparing legumes, grains, and seeds so you can keep them in your diet without
worrying about the negative effects of lectin protein. Prepare them mindfully,
and with the help of a few tried and true techniques to get the most out of
them:
1. Soak
Beans (canned or dried) in particular benefit from soaking, as do many harder
grains and pseudograins like oats, rye, barley, wheat, and quinoa. Soaking and
rinsing legumes and grains help to shake free starches, acids, and proteins,
making minerals more bioavailable as well as make them easier to digest. Put
yours in a larger bowl and cover with water by about 2 inches. Allow them to
soak for a few hours up to overnight. Drain fully and rinse again until the
water runs clear. As an extra tip: we like to add a 1” piece of kombu or dulse
seaweed to the water when soaking beans - it further helps to break down
lectins and make beans easier to digest!
2.Sprout
For most beans and seeds sprouting deactivates lectins completely. Why? Because
you’re no longer eating them in their contained form. Rather, since they’ve
begun the initial stages of germination, they’ve evolved from that seed state.
The nutrients are even more available when you sprout, and it’s a lot of fun
for the family when you have a hand in ‘growing’ your own food.
This works for almost all legumes except for alfalfa in which, interestingly,
lectins increase when sprouted!
3. Boil or Pressure Cook
It seems obvious that if you were going to eat legumes or grains that you would
boil or pressure cook them first - but these techniques actually have many
benefits and ridding beans of lectins is one of them. Studies show that boiling
soybeans, red beans, and many others at 212°F/ 100°C for a minimum of 10
minutes reduces lectins to negligible amounts.
4. Ferment
Fermenting foods is the act of allowing good bacteria to grow in the food. The
new good bacteria break down and convert would-be harmful proteins including
lectins. This is an ancient and common approach across many cultures to
consuming foods that are otherwise difficult to digest. In fact, fermented
foods are great for you for many reasons because that good bacteria is also
known as probiotics - one of the most important factors in overall gut health.
Just think of tofu, tempeh, miso, kefir, and natto as great examples of
fermented foods that would contain high levels of lectins prior to fermentation
and you can see why this technique is so far-reaching!
Dr. Amita Sachdev ND wants to see you and your family on a path towards your
optimal health, and we have the tools to help make that journey clearer and
easier. If you’re curious to learn more about how reducing or removing lectins
from your diet could be beneficial to you, please visit me at www.DrSachdevND.com and we will be happy
to have a detailed consultation with you.
Yours in good health,
Dr. Amita Sachdev ND
416 – 497 – CARE (2273)
References:
Rhodes, Jonathan M. Genetically modified foods and the Pusztai affair. BMJ. 1999 May 8; 318(7193): 1284.
Miyake K, Tanaka T, McNeil PL, 2007 Lectin-Based Food Poisoning: A New Mechanism of Protein Toxicity. PLoS ONE 2(8): e687. doi:10.1371/journal.pone.0000687
DeMarco, Vincent G., et al. Glutamine and Barrier Function in Cultured Caco-2 Epithelial Cell Monolayers. J. Nutr. July 1, 2003 vol. 133 no. 7 2176-2179.
http://gundrymd.com/remove-lectins/
http://www.greenmedinfo.com/blog/lectins-phytates-autoimmune-disease-separating-fact-fiction