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Diet & Nutrition

Are You Eating Foods High in Heavy Metals?

It’s very possible that the answer to this question is yes.

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UNSAFE AT ANY MEAL: What the FDA Does Not Want You to Know About the Foods You Eat

Adapted Book Excerpt: UNSAFE AT ANY MEAL: What the FDA Does Not Want You to Know About the Foods You Eat by Dr. Renee Joy Dufault (c) 2017. Used by permission. Square One Publishers (

Some of the most common food ingredients may be depositing toxic heavy metals into your body, contributing to the development of disease. Vegetable oils, food colors, corn syrups, and preservatives are the top sources of these ingredients—found mostly in processed food products—that will contribute to your body’s burden of heavy metal exposure. Although few studies have been conducted to determine the concentrations of heavy metals in food products, there seems to be some evidence to suggest the most common toxic heavy metals found in the food supply are inorganic mercury, lead, cadmium, and arsenic.

Measuring Heavy Metals in Food

Whether or not contaminants are found depends on the analytical method used to measure the heavy metal being studied. In the case of mercury, the monitoring results for the years 2008 and 2009 were omitted by FDA due to “issues in methodology.” The food samples collected by the total diet study during the years 2010 and 2011 were not analyzed for mercury. Some food samples collected after 2011 have been analyzed for mercury, but the new methodology is not stated in the updated FDA report. According to the 2016 publication, FDA reports finding mercury only in products containing fish. Since the methodology is not known and mercury was found only in products containing fish, we must assume the new methodology focuses exclusively on detecting the organic form of mercury.

It is interesting to note that in 2009, two studies published by two different research groups determined there were detectable levels of mercury in a variety of foods found in American grocery stores.

Organic vs. Inorganic Mercury

Why would FDA only look for organic mercury and not inorganic mercury, when the evidence suggests inorganic mercury is a widespread contaminant in the food supply? Organic methylmercury in fish is a known and accepted contaminant. Mercury exposure from fish consumption is an easy problem to address. The FDA simply advises consumers to limit their fish intake to reduce their mercury exposures. Inorganic mercury in the food supply is a controversial contaminant because it permeates the processed food supply. I cannot imagine the FDA advising consumers to avoid eating processed foods.

Inorganic mercury in the food supply is an inconvenient truth. Fixing exposure to inorganic mercury is harder than simply reducing your intake of certain foods; however, reducing your exposure is still extremely important.

There are certain amounts of heavy metals, such as arsenic, lead, and mercury, that are allowed in these food ingredients. This does not eliminate the significant risk of heavy metal exposure—these metals are able to displace zinc from the metal carrier protein metallothionein (MT), and this can lead to zinc losses from the body. Zinc losses adversely impact health by creating inflammation and stress. Heavy metal exposures and/or low zinc status are associated with Alzheimer’s disease, autism, hyperactivity, pica, type 2 diabetes, insulin resistance, and heart disease conditions. [Editor’s note: learn more at]

Spotlight on Sodium Benzoate

Sodium benzoate is not found naturally in the environment. It’s manufactured in three different ways. One of these methods involves using sodium hydroxide (which may contain mercury residue) in the neutralization of benzoic acid. Sodium benzoate is the end product of this neutralization. The chemical is used as a food additive (preservative) to control microbial, or bacterial, growth, and as a flavoring agent. It is most commonly found in soft drinks and cough syrup. In soft drinks, the chemical can combine with ascorbic acid (vitamin C) to form benzene, a chemical compound that may cause cancer. When used as a preservative, sodium benzoate must not legally contain more than the allowable level of 2 ppm lead. Manufacturing product specification sheets indicate food-grade sodium benzoate may contain up to 1 ppm mercury.