One. issue we’ve not discussed much around here is the fact that the Wheat Belly lifestyle in which we eliminate wheat and grains is also a reduced cadmium lifestyle.
Cadmium is a naturally-occurring heavy metal found in the earth’s crust. Industrialization with practices such as mining, coal-burning, smelting, etc. have mobilized cadmium in the environment, thereby exposing us to higher levels through water and air. Smokers have an especially high exposure, as the tobacco plant concentrates cadmium that is, in turn, inhaled by cigarette smoking. (This may be one of the factors causing coronary heart disease in smokers.)
We know that cadmium is concentrated in the kidney where it exerts toxic effects and, at sufficiently high levels, can cause kidney damage. Observational evidence also suggests that there is increased risk for cancers of the lung, breast, prostate, pancreas, urinary bladder, uterus, nasopharynx, and non-Hodgkin’s lymphoma, as well as osteoporosis and learning disabilities in children. Cadmium is cleared very slowly over many decades. It means that ongoing exposure causes cadmium to accumulate as we age.
Cadmium is surprisingly ubiquitous in the food supply occurring at higher levels in common foods such as sunflower seeds, iceberg lettuce, and cocoa powder. But, for most people, wheat and grains are the dominant source of dietary cadmium:
The Wheat Belly lifestyle in which we banish all wheat and grains is therefore a big step towards reducing your exposure to this toxic metal. Thankfully, the average intake of cadmium nowadays is around 5 mcg per day, a reduction compared to prior decades, a decline that likely derives from legislation reducing industrial air and water pollution, less reliance on phosphate fertilizers, and the decline in cigarette smoking. So cutting back on wheat and grains makes a considerable dent in your cadmium intake.
The benefits of eliminating wheat and grains derive from two factors:
- Wheat and grain products, including corn and rice, are dominant sources of dietary cadmium.
- Elimination of wheat and grains eliminates a major source of phytates. Recall that phytates bind positively-charged minerals such as iron, zinc, magnesium, and calcium. These minerals, when present, block the intestinal absorption of cadmium. When phytates are in the vicinity, they bind these minerals, making them unavailable to compete with cadmium, instead just lost in the toilet. If there is a lack of iron, zinc, or magnesium, cadmium absorption can increase as much as ten-fold.
Surely, there are other sources of cadmium. Smokers have 3- to 5-fold greater levels of cadmium in blood and urine due to inhalation of cigarette smoke. People who work in certain industries such as mining, paint manufacturing, farm work, plastics and others (See OSHA for a full listing.) can also experience occupational exposure. For us non-smokers who are not involved in a high-risk industry, however, cadmium exposure comes through food. Vegetarians are at special risk for cadmium accumulation, since their diet typically contains three-fold greater cadmium, while also lacking zinc and heme iron (both lacking in a vegetarian diet), as well as the phytate mineral-binding effect. (The USDA has performed an exhaustive analysis of the cadmium content of various foods, available to review here.)
But just by engaging in a wheat/grain-free lifestyle, you have gained substantial advantage in managing your cadmium status.