It’s amazing to see how many people are growing their own produce, supporting organic growers and adopting plant-based lifestyles for the planet’s sake, but did you know that some of the healthiest plant-based foods can contain anti-nutrient compounds that inhibit nutrient absorption?
Before you toss all your vegetables out the window, they are in fact loaded with beneficial nutrients as well—it just takes a little preparation for our bodies to reap those benefits. We’ve already taken a look at how to ferment your vegetables and how to sprout your grains, so now let’s look at ways we can cook our vegetables to minimize anti-nutrients and maximize nutrient density in our food.
First, what are anti-nutrients?
Anti-nutrients are compounds that are naturally found in plants/produce that they use as a defense mechanism against bacteria and predators. Plants, unlike animals, can’t run away from their predators (birds, squirrels, people) so they pump these compounds into their cells to block the natural absorption and assimilation of nutrients in your body so that you’re deterred from eating them.
Birds, insects, and other small predators are more likely to be deterred because of their size—if they eat a lot of a certain plant, it can immediately sugar-shock them into discomfort or even death. It would take eating a lot of vegetables to cause that type of reaction in a person, but over time anti-nutrients can disrupt your digestive tract, cause kidney stones, and other long-term health inconveniences.
Types of anti-nutrients and their risks and possible benefits
Anti-nutrients aren’t all bad. Depending on your current gut health and general food tolerance level, you might not be affected by them at all. Knowing this doesn’t mean we should avoid vegetables or even raw vegetables all together; it just means minimizing raw vegetables, knowing how to prepare them, and knowing whether a certain vegetable may inflame or irritate a current condition that you have.
1. Lectins
Found in beans, lentils, peas, soybeans, peanuts, tomatoes, potatoes, and eggplant
Con: These may decrease absorption of calcium, iron, phosphorus and zinc.
Pro: May benefit cardiometabolic health, immune health and help with cancer prevention (as long as you don’t have an autoimmune condition which makes you sensitive to lectins).
2. Saponins
Found in whole grains and legumes
Con: Can cause digestive disturbances like gas or bloating.
Pro: Can help reduce cholesterol, blood sugar and protect against certain types of cancer.
3. Glucosinolates
Found in brassicas (cabbage, kale, broccoli, etc.)
Con: People with thyroid disorders should be cautious as this anti-nutrient has the ability to bind with iodine (crucial mineral for thyroid health).
Pro: Can help detoxify your body, is high in antioxidants, and calms inflammation in the body.
4. Lectins
Found in tomatoes, peppers, eggplants, potatoes, nuts, grains, and legumes
Con: Harmful effects for your digestive tract and are known to bind to vitamins, proteins, and minerals in the body, preventing you from absorbing them.
Pro: Some types of lectin exhibit anti-fungal properties, are antimicrobial and have powerful antioxidants.
5. Oxalates
Found in leafy greens, nuts, seeds, and grains
Con: High intake is associated with the production of kidney stones as oxalates bind to calcium and cause a decrease in mineral absorption.
Pro: There aren’t many pros to oxalates themselves, but they’re found in many high-nutrient foods so the goal is to eliminate the oxalates almost altogether in order to reap the pros of the vegetables without the cons of the oxalates.
6. Phytates
Found in whole grains, seeds, legumes and nuts
Cons: Inhibit the absorption of essential minerals including iron, zinc, calcium and magnesium.
Pros: Potential anti-carcinogenic substance
Cooking your vegetables effectively rids most anti-nutrients
One study found that blanching vegetables, which means even briefly cooking or boiling the vegetables and pulling them out as they change colour, significantly reduces anti-nutrients.
Blanching helps reduce tannic and phytic acid, while proper boiling can deactivate oxalates, saponins, and lectins. For vegetables like brassicas (cabbage, broccoli, etc), boiling is one of the most effective ways (along with chopping) to reduce glucosinolates.
Depending on what you’re cooking, you may want to boil your chosen plant food for a longer or shorter period of time. Leafy greens don’t need to be cooked for nearly as long as cabbage or broccoli, and those don’t need to be cooked as long as grains. You just want to make sure to cook everything to the point where the vegetable/plant-based food changes colour so that the anti-nutrients have been eliminated.
The goal here isn’t to avoid vegetables or whole grains and legumes—it’s to empower you to know how to best prepare your plant-based foods for maximum benefits (and minimal health cons). Between fermentation, sprouting, and now cooking or boiling, you’re armed with the tools to get the most out of your garden grown goods.