Did you know that mold in peanuts or other nuts/seeds can produce harmful toxins? Symptoms of mold sickness can be debilitating, so protect yourself and your loved ones by understanding the risks of mold in your food and what to do about it! (This post is all based on peer-reviewed evidence-based research and backed by science.)
This content is for informational purposes only and not intended as medical advice.
- Is mold on food dangerous?
- Which Foods Can Grow Mold?
- Mold And Toxins in Food
- Toxins in Mold Can Cause Mold Sickness
- Mycotoxin Risk In Nuts?
- Are Moldy Nuts Avoidable?
- What is Mold Sickness?
- Mold Exposure Symptoms: What to Look Out For
- How Quickly Will Symptoms of Mold Exposure Occur?
- The Solution to Your Moldy Nuts
- How to Remove Mold From Nuts
- Is Roasting Enough?
- Final Thoughts: Do We Eat Nuts, Seeds, and Grain?
- Almond Milk Recipe
Is mold on food dangerous?
Mold can grow on a variety of foods, including peanuts. But did you know that under the right condition, mold can produce harmful toxins? Understanding the risks associated with eating moldy peanuts or other nuts or seeds is important for protecting your health. Keep reading to learn more about mold in peanuts and how to stay safe.
THE SKINNY: If you are here just for the solution and not the info about why mold may be present on your nuts and seeds and why that can make you sick, let us save you the trouble and give you the solution.
Mold on peanuts or other nuts and seeds is a very likely possibility. And the symptoms of mold sickness are not super pleasant. While toxins in the mold are not always present, the handling and storing of nuts, seeds, and grains can play a big role in minimizing your exposure.
- Make sure they are not old and PICK them over. Remove the ones that look old or spoiled, Fresh nuts/seeds are your friend so buy small amounts at a time.
- Rinse, rinse, and then rinse again
- Heat them, preferably in a dehydrator, or slow roast them in the oven
- Store them in an airtight clean container
Which Foods Can Grow Mold?
The truth is most foods are susceptible to mold. Fresh food with higher water content is more vulnerable to mold spores because of the nature of how these fungi grow. In addition, mold generally needs oxygen to thrive. That's why packaging and storage are so important. Finally, mold can also grow on food at any point in the journey from farm to table. In fact, much of the mold on peanuts or walnuts, for example, grows during the harvesting and transportation of these nuts.
Mold And Toxins in Food
Mold spores are microscopic fungi that require moisture and organic material to grow and produce energy. Unfortunately, some of these spores will produce mycotoxins when the right conditions are met. If fungi, or mold spores, are allowed to grow unchecked, the mycotoxin levels can become very high. While mold can have detrimental effects, it's the mycotoxins they produce that can lead to symptoms of mold exposure and toxicity.
There are two groups of fungi that produce mycotoxins to be aware of: field fungi which can be controlled with careful harvesting and storage fungi which are a risk once the food is in storage. Mold spores grow in high humidity, elevated temperatures, and when food is left exposed to damage. To prevent storage fungi from forming, we need to consider factors such as moisture, temperature, and damage. Mycotoxins can cause serious health risks, so understanding and controlling these fungi is essential.
Toxins in Mold Can Cause Mold Sickness
Moldy peanuts can produce harmful toxins called mycotoxins. There are 5 main groups of mycotoxins found in moldy nuts, seeds, or grains. These include aflatoxin, ochratoxin, fumonisin, zearalenone, and deoxynivalenol/nivalenol. The table below summarizes some of the places they are found and their effects on our health (it is not a complete summary by any means and is missing many nuts and grains but you get the idea).
Fumonisins and aflatoxins are of the greatest concern to our health and are the most present in grains and nuts (1). Aflatoxins were classified as a class 1 carcinogen by WHO, and interact with the function of the immune system, disrupt the digestive and urinary system, the reproductive systems, and the nervous system, and are mutagenic in bacteria (affect DNA).. pretty much they suck!!
Don't be fooled into thinking mycotoxins are rare. Shockingly, many research papers report that Aspergillus, the mold that produces mycotoxins, is often found in the nuts you eat every day. Meaning, if you're not careful, your favorite snack may have the potential to make you sick, or worse yet cause symptoms of mold sickness.
Mycotoxin Risk In Nuts?
As parents, the potential threat of mycotoxins in our food can be worrying. Research shows that contamination most often occurs prior to food going to market, with contaminated food often getting discarded. However, because aflatoxins are not evenly distributed throughout a bulk shipment, contaminated food is not always easy to detect. In fact, a study conducted by Tournes et al., (2015) found Aspergillus (the mold capable of producing the mycotoxin aflatoxin) in all nut samples tested.
The U.S. Department of Agriculture considers aflatoxins an unavoidable contaminant, even when good manufacturing practices are followed. To avoid potential health risks, it is important to recognize the risk factors for mold proliferation and take steps to prevent it. Mold spores grow in high humidity, elevated temperatures, and when food is left exposed to damage. To prevent mold growth, it is essential that all food producers, manufacturers, and consumers take proper storage and handling precautions.
Another way to reduce exposure to mycotoxins is to reduce animal product consumption and instead rely more on plant-based foods. This is because the prevalence of mycotoxins in animal feed has been a widely reported ongoing issue (2). So this is just another way you can help reduce your exposure and the potential risks.
Are Moldy Nuts Avoidable?
Despite the varying levels of contamination, research has shown that mold is virtually always present in nuts, seeds, and grains. Of these, walnuts, peanuts, pine nuts, almonds, and cashews seem to contain the highest levels of mold and yeast. And thus may have the greatest risk of causing symptoms of mold sickness.
These frightening reports of mold in grains, nuts, and seeds, and the mycotoxins they can produce, can cause alarm. But fear not - mycotoxins are not a guaranteed outcome of mold. They need the right conditions first! In fact, according to one study (3), positive mycotoxin levels were much less common than positive mold samples (1, 3, 4).
For parents looking to keep their family safe, the best way to reduce the risk of encountering mycotoxins is to eliminate the possibility that their food 'may' contain them. The answer? Remove the mold. If there's no mold, there's no chance of encountering mycotoxins.
What is Mold Sickness?
Exposure to mycotoxins from moldy nuts can cause symptoms of mold sickness. Mold sickness, also known as mold exposure or mycotoxicosis, is a condition that occurs when a person inhales or ingests mold spores (5). While most people will not experience any significant health issues, some may experience mycotoxicosis which can result in an acute or chronic disease episode. Acute toxicity can result in gastrointestinal symptoms or even respiratory problems, headaches, and fatigue.
It has been estimated that 25% of the world's crops are affected by mold or fungal growth. This has a significant impact on the cost of food production and on our health. In this post, we'll explore the causes of mold sickness and its potential impact on your well-being.
Mold Exposure Symptoms: What to Look Out For
Symptoms of mold sickness can vary from person to person depending on the severity of exposure and individual factors such as age, immune system strength, existing health conditions, and sensitivity to allergens. Common symptoms include (6,7):
- nasal irritation
- red eyes
- Shortness of breath
- Respiratory problems like wheezing
- Chest tightness.
- Skin irritation
If you suspect that you have been exposed to mold and are experiencing any of these symptoms, consult a medical professional promptly for diagnosis and treatment.
How Quickly Will Symptoms of Mold Exposure Occur?
How quickly mold sickness symptoms appear is not straightforward and depends on many factors (7). These include:
- Allergies and sensitivities
- Amount of mold you are exposed to
- Duration of mold exposure
- If there are mycotoxins present
The Solution to Your Moldy Nuts
As parents, protecting our families from potential hazards can be a daunting task. It's important to know that fungi can't grow or produce mycotoxins in dry foods, so proper storage and limiting moisture is your first line of defense. In addition, heating can also be a great option to effectively kill mold and helps with storage. When buying food products, it's best to check for any physical damage as deep-seated moisture can allow fungi to grow.
Additionally, look for dry-roasted nuts and seeds or pasteurized products to further reduce the likelihood of mycotoxins. Here are a few simple strategies to help keep your family safe: rinse, heat, dry, and check for any physical damage before buying.
How to Remove Mold From Nuts
1. Handpicking to reduce mold in nuts:
Carefully inspect your nuts for signs of mold and discard any that look moldy, discolored, or shriveled. For an extra level of assurance, buy from local, trusted brands. Don't be afraid to reach out to the company and ask them about their procedures for testing for mycotoxins, and their preparation and selection methods - including pasteurization.
2. Rinse and soak to reduce mold in nuts
You can reduce mold and water-soluble mycotoxins by up to 65% in some foods just by rinsing and soaking. This simple step can make a huge difference so it is worth a try. According to researchers, the best way to wash these foods is:
- 24-72 hour soak in a solution of water and sodium carbonate (the gold standard).
- The best ratio is to add 1 teaspoon for every 3 cups of water.
- Rinse with a solution of 1 cup of vinegar and 1 gallon of water.
- A simple water rinse
Since the research on this is scarce, recommendations of soaking times per nut or grain just don't exist yet. And while there are many blogs on the recommended soaking times, I believe these guidelines are based on increasing the nutrient bioavailable and reducing phytic acid and not on mold reduction.
3. Dehydrate to reduce mold in nuts
Despite mycotoxins being heat resistant, heat is an important step in reducing mold spores.To minimize the chances of mold proliferation, it's important to eliminate moisture. Procedures for dehydrating nuts, seeds, and whole grains are well documented (like here). Although exact methods may vary, 12 hours at 150°F is recommended as the gold standard.
- Salton's dehydrator, available on Amazon, is the perfect size and budget for families like ours who don't consume excessive amounts of nuts. It's simple to use and of great quality; a great value for money.
4. Proper storage to reduce mold in nuts
Buying quality nuts, seeds, and grains is the first step but, don't stop there. During storage, make sure they are kept away from moisture, temperature fluctuations, and potential damage. For the most effective storage, store them in an airtight glass jar in the freezer or in a cool, dark place. So the biggest takeaway to avoid mold in peanuts, and the potential symptoms of mold sickness, is to rinse (or soak), dry, and store them properly!
PICK OVER, RINSE, HEAT, AND STORE
Is Roasting Enough?
Despite heat being effective against mold spores, mycotoxins are resistant to heat treatment. Studies of food preparation have confirmed this - frying, cooking, and roasting are unsuccessful at removing mycotoxins from food.
But why? Because Aflatoxins have a decomposition temperature of 237 to 306 degrees Celsius. Though some methods may be more effective than others (such as pressure cooking rice which can reduce mycotoxins by 78-88 percent), it is extremely hard to completely remove mycotoxins.
That's why prevention is key. Buying fresh nuts, seeds, and grains from a trusted company and storing them properly can help avoid Mold and the symptoms of mold sickness. It is important to remember, however, that trace exposure to mycotoxins may not be an issue if you have a healthy, balanced diet and functioning detox pathways. If you are concerned, however, then limit these foods in your diet.
Final Thoughts: Do We Eat Nuts, Seeds, and Grain?
Vegan and gluten-free diets rely heavily on nuts, seeds, and grains. And with the current rise in plant-based milk, it is becoming increasingly important to understand the role mold can play in food. What I learned while researching this topic is that it is essential to understand the risks of mishandling and improper storage of our food. After all, you don't want to unknowingly put your family at risk of consuming moldy products.
Almond Milk Recipe
Nuts and seeds make the best plant-based milk. For a great recipe on making creamy almond milk check out this post, Creamy Almond Milk.
Anyhoo thank you for reading! We are working on more evidence-based research to commonly asked questions so be sure to comment down below if you would like something reviewed. Oh and come check me out on Instagram and say hello!
And if you want more now be sure to check out these:
- 15 minute no bake healthy bliss balls
- Benefits of a whole food balanced diet
- Quick and Easy Creamy Almond Milk Recipe
- Navigating Picky Eaters: Tips, Tricks & Meal Ideas
- Tournas, V., Niazi, N., & Kohn, J. (2015). Fungal Presence in Selected Tree Nuts and Dried Fruits. Microbiology Insights, 8, 1-6.
- Pereira C., S. Cunha S. C., Fernandes J., O. (2019) Prevalent Mycotoxins in Animal Feed: Occurrence and Analytical Methods Toxin. Basal. 11(5): 290.
- Abdel-Gawad KM1, Zohri AA.(1993) Fungal flora and mycotoxins of six kinds of nut seeds for human consumption in Saudi Arabia. Mycopathologia. Oct;124(1):55-64.
- Jimenez, M., Mateo, R., Querol, A., Huerta, T., Hernandez, E..(1991) Mycotoxins and mycotoxigenic moulds in nuts and sunflower seeds for human consumption.
- Bryden, W. L. (2007) Mycotoxins in the food chain: human health implications. Asia Pac J Clin Nutr 2007;16 Suppl 1:95-101.
- Mayo Clinic. (2023). Mold allergy: Symptoms and causes. Retrieved from [URL]
- Healthline. (2023.). How Long Does It Take to Get Sick from Mold Exposure? Retrieved from [URL]
- World Health Organization (2018) Department of food safety and zooness. Foodsafety Digest (http://www.who.int/foodsafety/FSDigest_Aflatoxins_EN.pdf)