Imagine you’re a plant out in the wild. You’re soaking up sunshine and getting taller and greener by the day. You’re full of nutrients. Life is pretty good.
The only trouble is these damn herbivores. Insects, deer, small woodland animals - they keep strolling in and eating your neighbors. If you aren’t careful, you’ll end up as lunch.
What’s a smart plant to do?
Plants go to great lengths to avoid getting eaten. Some turn to poison, although that doesn’t always work out; caffeine is a poison that happens to be very beneficial to humans. The coffee plant screwed up. And while poison is often effective, making it takes a lot of resources. For that reason, many plants opt for a gentler defense system. Instead of poison, they make antinutrients.
Antinutrients are a plant’s way of warding off predators. Many are insecticides that flat-out kill hungry insects, but antinutrients also impact larger animals. In mammals, antinutrients either prevent nutrient absorption or cause digestive damage. The idea is that the animal will eat the plant, feel sick or unsatisfied, and move on in search of better food sources.
A lot of common foods have antinutrients in them. At best, antinutrients decrease the nutritional value of your food a little bit. At worst, they disrupt your digestive tract or make you sick.
Fortunately, most antinutrients are easy to either deactivate or avoid. In fact, some are actively good for you, provided you get them in the right doses.
The three most common antinutrients are lectins, oxalates, and phytic acid. Let’s take a look at what each one does, which foods have them, and how to approach them in your diet.
Lectins: bad for some people, fine for others
Lectins can damage your gut and cause digestive issues...if you’re sensitive to them. If you’re not, lectins are no big deal.
As food passes through your gut, it drags against your intestinal wall and causes minor tears. Sounds bad, but it’s not a big deal; you repair your intestinal wall pretty quickly.
Lectins slow down the repair process, which can cause irritation and poor digestion . You can see why a plant would want to make lectins: predator eats plant, predator gets a stomach ache from lectins, predator leaves plant alone next time.
Legumes (beans, lentils, peanuts, and especially soy), whole grains, nightshade vegetables (potatoes, peppers, eggplant, tomatoes), nuts, and dairy all contain higher levels of lectins .
However, cooking or fermenting deactivates the vast majority of lectins. If you’re lectin-sensitive, you may want to avoid uncooked peppers, tomatoes, nuts, and dairy. But for the vast majority of folks, the above foods are fine as long as you cook the lectins out of them. It’s worth noting that lectins withstand dry heat pretty well, but the vast majority (>95%) fall apart in wet heat (boiling, steaming, pressure cooking, etc.).
How do you know if you’re sensitive to lectins? Eat some raw peppers or a handful of nuts and see if they cause digestive issues. If you feel fine, you’re probably okay with lectins.
Oxalates: a reason to skip raw veggies?
Again, not for most people.
Oxalates (also called oxalic acids) are in some raw veggies, including cruciferous vegetables like cauliflower and kale, spinach, beets, chard, and rhubarb . They get a lot of heat for being damaging antinutrients, and they sound scary, but they’re actually pretty harmless as long as you’re in reasonably good health.
Oxalates aren't that big a deal because your gut bacteria deactivate 85-98% of the oxalate you eat . The small amount of remaining oxalate binds to minerals (particularly calcium, magnesium, and iron) and forms tiny crystals that you pee out.
If your gut biome is imbalanced or your digestive enzymes are weak, however, you may not be deactivating enough oxalate; in that case, oxalate can builds up and cause kidney stones. About 80% of kidney stones are made of calcium oxalate .
So if your gut is in rough shape, maybe you should cook higher-oxalate veggies while you focus on building a stronger gut. Try taking a probiotic with Lactobacilli and Bifidobacteria - they’re both great at breaking down oxalates (and they’re both in Ample, by the way). Or, if your family has a history of kidney stones or gout, you may want to avoid high-oxalate raw veggies altogether.
But if you’re generally pretty healthy, go ahead and eat your dark, leafy greens, raw or otherwise. Your body will handle the oxalates just fine.
Phytic acid: good in small doses, bad in large ones
Of the three compounds we’ve talked about, phytic acid (also called phytate) is the biggest antinutrient, and the truest example of the term. Phytic acid prevents absorption of nutrients by binding to them so you can't use them. Phytic acid latches onto zinc , calcium, magnesium, iron , and a couple more minor micronutrients as they pass through your small intestine. Eating a lot of phytic acid decreases the health benefits of common foods and can lead to nutrient deficiencies , and cooking doesn’t deactivate phytic acid.
What’s a nutritionally savvy person like you to do?
First, make note of plant foods that have a high phytate content:
- Whole grains (wheat, whole-grain rice, quinoa). Note that many gluten-free grains still have phytic acid
- Legumes (beans, peanuts, soy)
- Nuts (very high in phytic acid, although you usually don't eat a lot of them)
- Cocoa powder (again, very high in phytic acid, but you usually use a small amount)
Keep in mind that in order for phytic acid to bind to nutrients, it has to actually come into contact with them. Of the above foods, grains and legumes tend to be the most commonly eaten. You probably aren’t eating fistfuls of nuts or cocoa powder at every meal. So if you do eat a lot of grains and legumes at every meal (say, as beans and rice), try skipping them now and then, or have them a couple hours before/after other meals. You’ll get more minerals out of your food. You can also try sprouting your foods to get rid of phytic acid and improve the foods' digestibility.
That said, don’t worry too much about eliminating all phytic acid. While large amounts can be harmful, a small amount of it is actually good for you - phytic acid is a surprisingly promising way to kill cancer cells . It also prevents oxalate - the last antinutrient you read about - from forming kidney stones . And besides, if you’re eating a varied diet with plenty of greens and protein, you probably have some minerals to spare. Giving a few of them up to phytic acid isn’t the end of the world.
All in all, antinutrients aren’t that big a concern for most folks. They’re a minor part in a much bigger nutritional picture. If you’re particularly sensitive to lectins or you’re working your way through an imbalanced gut, now you know how to deal with antinutrients until you’re feeling good again. If you’re reasonably healthy, don’t worry about them. Keep thriving. Thanks for reading!