Why It's Important to Know What Anti-Nutrients Are

It's important to know what anti-nutrients are because they're in a lot of different foods. Learn more about them in today's article!
Why It's Important to Know What Anti-Nutrients Are

Last update: 03 May, 2022

Knowing what anti-nutrients are and how they affect you is important. That’s because their presence depends on whether we absorb more or less of some key nutrients. This is the case with minerals like iron and calcium. 

This is especially interesting in the case of people who follow a vegan diet or who have to put special emphasis on one of these important nutrients. Often, people can’t easily absorb the nutrients in food. 

For example, some plant components prevent us from properly absorbing nutrients like minerals and proteins. And, some of those are found, paradoxically, in the food itself. These components are also known as anti-nutrients. 

However, and although their name may have a negative connotation, they’re not harmful. Therefore, you shouldn’t obsess over their presence. Next, we’ll look at why it’s important to know what anti-nutrients are and that they don’t always affect you in a harmful way.

What are anti-nutrients and how do they work?

Anti-nutrients are chemical compounds that can be found naturally in food. Although they’re varied, they’re able to bind to certain nutrients which makes it more difficult for the body to absorb. In addition, they can make certain nutrients more bioavailable in some foods than in others. 

However, we can’t say that anti-nutrients adversely affect health. They don’t ‘steal’ nutrients from our body nor do they end up with their reserves. However, they will make it difficult for the body to absorb all the minerals in food.

Types of food that are high in minerals.

It’s important to know what the main anti-nutrients are

There are many different anti-nutrients. Each one usually has its own field of action and they’re in certain foods. Let’s take a look.

Phytic acid or phytates

This is an organic acid present in vegetables that serves as a phosphorus reserve. It reduces the absorption of minerals like iron, calcium, zinc, and magnesium in food. You can mainly find it in legumes, seeds, and whole grains.


Tannins are a type of chemical compound belonging to the group of polyphenols. They can combine with other molecules, like minerals and vitamins. They deactivate digestive enzymes and precipitate proteins.

You can find them in a wide variety of plants, including legumes, seeds, and nuts. However, the best-known sources are cocoa, wine, tea, and coffee. 


They inhibit the absorption of iodine, which can interfere with the normal functioning of the thyroid gland. In this case, those who already have an iodine deficiency or who suffer from hypothyroidism are more susceptible to its action.

Protease inhibitors

This type of anti-nutrient doesn’t affect the absorption of minerals, but it prevents us from digesting proteins well. Protease is an enzyme that helps us break down and digest proteins in foods.

Oxalic acid

This acid is mainly in foods like potatoes, spinach, tea, berries, or beets. It binds to calcium and forms a compound that our intestines cannot absorb. It can bind to calcium in the food itself or other components in the same food. 

Can we reduce anti-nutrients in food?


As we’ve discussed, anti-nutrients reduce the absorption of some minerals.

In addition, some practices in the kitchen allow us to deactivate them or reduce their presence. You can decrease some of them, like glucosinolates and phytic acid, through soaking, cooking, and sprouting.

Because of that, it’s a good idea to soak legumes and whole grains before cooking them. Nuts and seeds should also be eaten pre-soaked or lightly toasted, not fried or salted. 
People at risk of a nutrient deficiency should pay more attention. This is the case, for example, with people who have osteoporosis due to calcium deficiency or anemia due to iron deficiency.

In these cases, it’s best to:

  • Not drink tea, coffee, or cocoa during main meals
  • Take mineral supplements outside of mealtimes
  • Take foods rich in vitamin C that will help you absorb iron

Anti-nutrients aren’t always negative

We often talk about anti-nutrients being negative for our health because they decrease our ability to absorb minerals. However, they also have positive effects on our bodies. 
The tannins in green tea appear to have protective properties against some types of cancer. Whole foods, seeds, and legumes also have other components like fiber, vitamins, and antioxidants, which are beneficial.

In fact, long-term studies show that diets rich in legumes, nuts or green leafy vegetables have a positive impact on our health. The same goes for whole grains, seeds, berries, and others. 

People who follow these diets tend to have better body weight, lower incidence of some types of cancer, lower risk of cardiovascular disease and type 2 diabetes.

For this reason, we shouldn’t be afraid of these foods even if they have anti-nutrients. Only those people who are at risk of being deficient in these minerals should pay special attention.


Completing eliminating anti-nutrients from your diet is difficult and we don’t recommend it. That’s because foods that contain a lot of anti-nutrients are very beneficial for your health.

Eating a variety of foods in the same meal helps us compensate for nutrient losses. In addition, if we consider soaking, cooking, roasting, or germinating seeds, whole grains, and legumes, we can significantly reduce the action of anti-nutrients.

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