By Carol Chuang, MS, CNS, CMTA, FDN

Americans love peanuts, from peanut butter sandwiches to peanut butter cookies, energy bars, and desserts. Americans consume over 1.5 billion pounds of peanut products annually. Peanut butter is consumed in 90 percent of US households. The average American eats more than 6 pounds of peanuts per year.

While this all-American "nut" (it is actually a legume) has been touted as healthy and an affordable source of protein, vitamin E, folate, manganese, niacin, and even resveratrol (antioxidant found in red grapes), peanuts may not be the health food it has been proclaimed to be.

Many people have chosen to avoid peanuts and peanut butter due to:

• Food allergies. The rate of peanut allergies among American children have more than tripled in the last decade.
• High omega-6 fat content. Compared to other nuts such as almonds, macadamia nuts, or cashews, peanuts have a relatively high omega-6 content. Without enough omega-3 to balance it off, omega-6 becomes inflammatory in the body. Also, roasting peanuts in high temperature damages the fragile omega-6 fat, turning it into oxidized fat which is a source of free radicals that can cause DNA damage.
• Phytic acid. Present in all nuts, seeds, grains, beans, and legumes, it binds to nutrients in food and prevents the body from absorbing such nutrients. Roasting does not remove the phytic acid, however, soaking, sprouting, and fermentation will eliminate most of it.
• Lectins. These are carbohydrate-binding proteins universally present in plants and animals. Lectins can damage your small intestinal lining if you are sensitive to the particular lectins. Some lectins are destroyed by soaking, sprouting, and fermentation, but peanut lectins are more difficult to destroy. They are also heat resistant, so roasting the nuts will not help.
• Galaco-ligosaccharides. They are a type of carbohydrates that can cause unpleasant digestive issues for certain people, especially those with irritable bowel syndrome (IBS). 
• Pesticides. Peanuts are generally a heavily sprayed crop, therefore, you should always purchase organic peanut products.

But there is another important reason to be wary about peanuts: Aflatoxins.

What Are Aflatoxins?

Aflatoxins are toxins produced by a mold called Aspergillus that thrives in the soil around crops grown in a hot, humid environment. Some crops are particularly vulnerable to aflatoxins, including:

• Peanuts 
• Corn
• Oil seeds such as cottonseed
• Wheat
• Tree nuts such as pecans

Peanuts favor warm weather and plenty of rain water or irrigation. Due to their thin, porous shells, peanuts are prime candidates for fungal invasion during growth and storage. A crop can be infested by aflatoxins as a result of improper storage in a high-humidity environment. Both organic and regular peanuts are equally susceptible to aflatoxins.

Aflatoxins Are Toxic

Aflatoxins are carcinogenic and have been shown to cause liver cancer in lab animals by reacting with DNA, resulting in mutations of the p53 gene, also known as the tumor suppressor gene. Without p53, the immune system is suppressed and the ability to halt tumor formation is gone.

In humans, there are studies linking aflatoxin ingestion with higher liver cancer rates in a number of developing countries where consumption of aflatoxin-contaminated foods is high. Scientists believe that aflatoxin causes liver cells to die and reduces the liver's ability to produce glutathione. Glutathione is a powerful cancer-fighting antioxidant as well as a detoxifying agent that helps the body eliminate heavy metals and toxins.

The US Food and Drug Administration (FDA) is well aware of the toxic effects of aflatoxin and has set a limit of 20 parts per billion (ppb). Limits in Canada and Europe, however, are substantially lower. 

Aflatoxins are very stable and are not easily destroyed by high heat, such as cooking, baking, or roasting. Presently, there are no long-term studies showing that low exposure over extended periods of time is safe and that it will not accumulate to a significant toxic load on the body. Therefore, to be prudent, those who have cancer or whose cancer is in remission should not be eating peanuts on a regular basis.

How To Reduce Your Aflatoxin Exposure?

First and foremost, eat less of the foods that are most frequently contaminated with aflatoxin, including peanuts, corn, oil seeds such as cottonseed, wheat, and tree nuts like pecans.

Buy quality. Never buy nuts that look moldy, discolored, or shriveled. Always buy from companies who take aflatoxin contamination seriously. For example, MaraNatha asserts that its peanut butter is virtually aflatoxin free. Similarly, Whole Foods claims that the aflatoxin level of its 365 brand peanut butter ranges between 0-10 ppb, well below the FDA level.

Never buy in bulk. The do-it-yourself nut butters found in health food stores typically have higher levels of aflatoxin as these nuts are often stored in the grinding chamber for weeks or months. Also, national brands are regularly checked for aflatoxin levels, the bulk ones are   not.

Buy quality meats and dairy. Since aflatoxin is found in the milk and meat of animals given contaminated feed (such as corn), it is always preferable to choose grass-fed beef and dairy products from a reputable farm.

Provide your body with the antidote. Eat more of these foods that have been found to reduce the carcinogenic effects of aflatoxin - carrots, celery, garlic, onions, parsnips, parsley, chlorophyll (found in green vegetables), chlorella, and spirulina.

© Carol Chuang 2014

About the Author 

Carol Chuang earned a Master of Science degree in Nutrition from Huntington College of Health Sciences. She is a Certified Nutrition Specialist from the American College of Nutrition, a Certified Health Counselor from the Institute for Integrative Nutrition, a Certified Metabolic Typing Advisor, a Certified Functional Diagnostic Nutritionist, and a Certified Gluten Practitioner. She is also board certified by the American Association of Drugless Practitioners.

Carol is a Professional Member of the American College of Nutrition and the Price-Pottenger Nutrition Foundation. Apart from having her private practice counseling individual clients, she writes a monthly nutrition newsletter, and conducts regular seminars on various topics of nutrition and wellness.