Are Anti-Nutrients to be Avoided at All Times?

Digesting your meal isn’t always easy. This is because many plant foods contain “anti-nutrients”. Anti-nutrients are substances that block the absorption of nutrients from your meal. They are beneficial for the plant itself as they serve to against from bacterial infections and being eaten by insects.  The concern however is whether anti-nutrients will inhibit our ability to take quality nutrition from our meal.

Are Anti-Nutrients All Bad?

The pros and cons of anti-nutrients when it comes to long term health is still under investigation. Previously, recommendations (particularly for people with a plant-heavy diet) were to reduce or avoid dietary anti-nutrients where possible. Howeve,r emerging evidence suggests we may not need to be so drastic in our approach.

The Pros and Cons of Common Anti-Nutrients

There are many compounds in foods that we classify as anti-nutrients, but the most common ones include:

1. Lectins

Lectins are a group of proteins found in legumes (beans, peanuts, and soybeans), nightshades (tomatoes, peppers and potatoes), and wholegrains.

  • The Cons: They can interfere with the absorption of zinc, calcium, iron and phosphorous. Concentrated amounts of lectins in raw legumes are known to be harmful. Animal studies suggest that they may harm the gut lining and even compromise immune function. There are also other rare possibilities such as an autoimmune response to lectins or dysbiosis in the gut related to high lectin consumption.

  • How to Reduce Them: Cooking at an appropriate temperate and for an appropriate length of time eliminates the risks of lectins. Other methods include soaking, sprouting and fermenting beans.

  • The Pros: Lectin containing foods are predominantly high in vitamins, minerals, phytonutrients, and fibre. Animal studies suggest that lectins may boost immune activity, and because of their anti-bacterial effect they may play a role in keeping our guts free from pathogens. Further benefits include blood sugar regulation, increased digestive function and even anti-tumour activity. More research is needed, but the potential for benefit is certainly present.  

2. Tannins

Tannins are a class of antioxidant found in teas such as green and black tea, coffee, wine and chocolate. The bitter flavour characteristic of these foods is usually attributed to their supply of tannins.

  • The Cons: Tannins have anti-nutritional properties in that they can hinder both digestion and metabolism, as well as negatively affect the absorption of iron from foods.

  • How to Reduce Them: Choose white wine over red wine, white beans over red beans, milk over dark chocolate and peel fruits to reduce their tannin content (as the tannins tend to concentrate in the skins). Generally, you’d need to avoid green and black tea to reduce your tannin intake from these.

  • The Pros: Tannins don’t pose a problem for most people. In fact, they have anti-cancer properties. Tannins remove harmful microbes from the body and have anti-pathogenic activity against bacteria, viruses, and fungi.

3. Phytates

Phytates (phytic acid) are mostly found in grains, seeds and legumes.

  • The Cons: Phytates reduce the absorption of minerals such as iron, zinc, magnesium and calcium from a meal.

  • How To Reduce Them: Soaking, sprouting and fermenting foods such as cereal grains, seeds and legumes help to reduce the phytate content. Combining these methods substantially reduces the phytate content.

  • The Pros: For most people, phytates are beneficial. They have antioxidant properties and may protect against kidney stones. It has been suggested that phytates may be part of the reason why wholegrains are associated with a reduced risk for colon cancer.

4. Oxalates

Oxalates are naturally occurring substances found in the highest concentration in beans, beer, beets, berries, chocolate, cranberries and dark green vegetables such as spinach.

  • The Cons: When eaten, oxalates can bind to minerals to form compounds such as calcium oxalate and iron oxalate. This mostly occurs in the gut but can also happen in the kidneys and other parts of the urinary tract. In sensitive people, high oxalate diets have been linked to increased risk for kidney stones as well as other health concerns. Because oxalates bind to minerals, this prevents the body from absorbing and utilising these minerals, which can contribute to deficiencies.

  • How to Reduce Them: Firstly, choose low oxalate foods and soak or boil oxalate-rich vegetables to reduce their content. Further strategies would be to drink plenty of water and add calcium sources to oxalate-containing meals.

What You Should Know

Anti-nutrients are abundant in plant foods. They can reduce the nutritional value of these foods which may contribute to deficiencies or other negative health outcomes in prone individuals.  As with many things in life, there is very little that is exclusively good or bad. There are times to be more drastic when it comes to dietary restrictions, for example if you already have a mineral deficiency. However for most of us these anti-nutrients may be perfectly safe to consume and even provide some benefit.

Shopping Cart
Scroll to Top
Open chat
Please message us here if you have a question.