Phytates

What are phytates?

Phytates or phytic acid are compounds found in whole grains, legumes, seeds and nuts. These compounds accumulate in plants as a way to store phosphorus, a mineral essential for growth. During seed germination, plants release enzymes that break down phytic acid, thereby releasing phosphorus that aids in plant growth.

For humans, phytic acid is considered an “antinutrient” due to its ability to bind with essential minerals such as iron, zinc, magnesium and calcium, forming compounds that our digestive system cannot easily absorb. Consequently, a diet rich in phytates could, in theory, cause mineral deficiencies in people who do not have varied access to other foods rich in these nutrients.

Phytates: friends or enemies?

The term “antinutrient” has caused many people to perceive phytates as something negative, but recent studies have shown that phytic acid may offer some health benefits. Below are some of its possible positive and negative effects on the human body.

Negative effects: binding with minerals

The main argument against phytates is their ability to bind to minerals and reduce their absorption. This phenomenon is especially relevant in vegetarian or vegan diets, since phytates are abundant in plant foods. The impact on mineral absorption may vary depending on the type of mineral and the characteristics of each person’s diet:

• Iron and zinc: Phytates can reduce the bioavailability of non-heme iron (found in vegetables), which is problematic in people with anemia or in those who depend on plant sources for these nutrients. The same goes for zinc, an essential mineral for the immune system.

• Calcium and magnesium: While phytates also bind to calcium and magnesium, the effects of this binding are less clear and, in many cases, the impact is not as severe.

In general, the negative effects of phytic acid on mineral absorption are more worrying in populations that have a poorly varied diet and limited mineral intake, such as in certain areas of Africa or Asia where diets are based on cereals and legumes without a wide availability of other foods.

Positive effects: antioxidants and disease prevention

Despite their reputation as antinutrients, phytates also have beneficial properties, especially in terms of preventing chronic diseases. Some of the most notable beneficial effects are:

1. Antioxidant properties: Phytates have the ability to neutralize free radicals, compounds that can damage cells and contribute to the development of diseases such as cancer and premature aging. As antioxidants, phytates may play a protective role in preventing these conditions.

2. Cancer prevention: Several studies suggest that phytic acid could reduce the risk of certain types of cancer, such as colon cancer. Their ability to inhibit the proliferation of cancer cells and stimulate the activity of the immune system means that phytates are considered potentially beneficial in cancer prevention.

3. Blood glucose control: Some studies indicate that phytic acid can help regulate glucose levels and reduce the glycemic index of foods, which is especially relevant for people with type 2 diabetes or those at risk of developing it.

4. Prevention of kidney stones: Because phytates can reduce calcium absorption in the intestine, some researchers have hypothesized that they could prevent the formation of calcium oxalate kidney stones, which is the most common type of kidney stones.

How does food preparation affect phytates?

There are methods to reduce the phytate content in foods, allowing better absorption of minerals and taking advantage of their benefits. These preparation methods have been traditionally practiced in many cultures:

1. Soaking: Soaking legumes and grains for several hours (even overnight) significantly reduces phytate content. Soaking activates enzymes that break down phytic acid.

2. Germination: Germination or sprouting is another way to reduce the phytate content, since the natural growth process of the plant decreases its concentration.

3. Fermentation: Fermentation of foods like sourdough bread also breaks down phytates. This process is especially beneficial in whole wheat breads, allowing better absorption of minerals such as iron and zinc.

4. Long cooking: Although not as effective as soaking or sprouting, prolonged cooking can slightly reduce phytate content.

Should we avoid phytates?

The answer to this question depends on each person’s dietary and health context. In general, for healthy people with a varied and balanced diet, phytates should not represent a significant problem. Those who consume a largely vegetarian or vegan diet should be more aware of how to get enough minerals, incorporating food preparation techniques that reduce phytate content and opting for plant sources rich in iron and zinc, such as legumes, nuts and whole grains, which are often consumed with vegetables rich in vitamin C (which increases iron absorption).

In populations where intake of essential minerals is low or access to varied nutrient sources is limited, phytates may represent an increased risk of mineral deficiency. In these cases, strategies to reduce dietary phytates or to increase mineral bioavailability become more critical.

Conclusion

Phytates, far from being a simple “antinutrient”, are multifunctional compounds with both positive and negative effects on human health. While their ability to bind to minerals may reduce their bioavailability, they also offer antioxidant properties and may contribute to the prevention of diseases such as cancer, diabetes, and kidney stones. The key to reaping the benefits of phytates while minimizing their negative effects lies in proper food preparation and maintaining a balanced diet.

It is important that the focus on nutrition evolves to recognize the value of phytates in a broad context and that the reductionist view of considering them solely as antinutrients is abandoned. In the end, as with many aspects of nutrition, balance and variety are essential for optimal health.