What Exactly Is Phytic Acid?
Phytic acid, or phytate, is a natural compound present in the seeds, grains, and nuts of plants. Its primary purpose is to store phosphorus, which the seed uses for energy during germination. For this reason, it is sometimes called an "anti-nutrient" because when humans consume it, it can bind to essential minerals like zinc, iron, calcium, and magnesium in the digestive tract, hindering their absorption. The human body lacks the necessary enzyme, phytase, to effectively break down phytic acid on its own.
Phytic Acid Content in Cashews
Cashews are in the category of nuts containing phytic acid, though they are not the highest. Research indicates that the phytic acid content in cashews can range, but they are generally considered to have a moderate amount compared to some other tree nuts. The exact concentration can vary based on factors like the cashew variety and processing methods. A scientific review shows that cashew nuts can contain approximately 0.19 to 4.98 grams of phytic acid per 100 grams of dry weight. For most people eating a balanced diet, the phytic acid in cashews and other nuts is not a major concern. However, individuals on heavily plant-based diets or those with existing mineral deficiencies may want to take steps to reduce their intake.
How to Reduce Phytic Acid in Cashews
Fortunately, several simple kitchen techniques can help reduce the phytic acid content in cashews and other nuts, making their nutrients more accessible and improving digestibility.
Method 1: Soaking
Soaking is one of the most common and effective ways to neutralize phytic acid. This process activates the natural enzymes in the nut, which helps to break down the compound.
Steps for Soaking:
- Place raw cashews in a bowl and cover them completely with filtered water.
- Soak cashews for a shorter duration than harder nuts. A soaking time of 2-4 hours is often recommended to avoid them becoming too soft or slimy. Soaking overnight is also an option, but keep them in the refrigerator and be mindful of potential texture changes.
- Drain the cashews and rinse them thoroughly with fresh water to wash away the phytic acid that has been released.
- After soaking, they can be used immediately in recipes for a creamy texture, or they can be dried and roasted for a crispier feel.
Method 2: Roasting
Cooking cashews through roasting can also reduce their phytic acid content. The heat helps to break down the anti-nutrient. It is important to note that the degree of reduction can vary depending on the temperature and duration of the roasting process. This is one of the reasons store-bought roasted cashews often have a lower phytate level than their raw counterparts, as the commercial preparation process (which includes steaming or roasting to remove a caustic shell resin) also reduces phytic acid.
Phytic Acid Comparison: Cashews vs. Other Nuts
To put the phytic acid content of cashews into perspective, the table below compares them to other common nuts. This data highlights that while cashews contain phytic acid, their levels are often lower than nuts like almonds and walnuts, though there is still a significant range.
| Food (per 100g dry weight) | Phytic Acid Content (grams) | Notes |
|---|---|---|
| Almonds | 0.35–9.42 | One of the highest levels among nuts. |
| Walnuts | 0.20–6.69 | Also contains significant phytic acid. |
| Cashews | 0.19–4.98 | Moderate levels, with a wide range. |
| Brazil Nuts | 0.29–6.34 | Generally high. |
| Macadamia Nuts | Lower than most nuts | One of the lowest phytic acid contents. |
The Dual Nature of Phytic Acid: Potential Benefits
It is important to remember that phytic acid is not entirely negative. Like many substances in whole foods, it can have both positive and negative effects depending on the context of your diet and overall health. For instance, phytic acid has been shown to possess antioxidant properties that may protect against oxidative damage. Researchers have also explored its potential role in managing insulin resistance and its protective effects against certain types of cancer, like colon cancer. For individuals with a balanced diet and no underlying mineral deficiencies, the benefits of the minerals and healthy fats in cashews generally outweigh the mild inhibitory effects of the phytic acid.
Conclusion
In summary, cashews do contain phytic acid, but this should not deter you from enjoying their numerous health benefits. By utilizing simple, traditional preparation methods such as soaking and roasting, you can effectively reduce the phytic acid content and improve the bioavailability of their minerals. For most people, a handful of cashews as part of a varied diet poses no risk of mineral deficiency. Understanding the balance of anti-nutrients and beneficial compounds in whole foods like cashews empowers you to make more informed choices about your nutrition. For more information on the science behind nutrient absorption, you can consult research from reliable sources such as the National Institutes of Health.(https://pmc.ncbi.nlm.nih.gov/articles/PMC4325021/)
