Low-level cadmium toxicity and fatty liver disease
A recent study concluded that it’s more difficult for adults today to maintain the same weight as those a few decades ago, even with the same levels of food intake and exercise. However, the study authors also suggested an array of factors that might be contributing to the rise in obesity: exposure to chemicals such as pesticides and flame retardants, prescription drugs such as antidepressants, and altered microbiomes linked with antibiotic use in livestock.
The heavy metal cadmium may belong on that list of chemicals, not primarily as a booster of obesity, but instead in connection with the increase in prevalence in NAFLD (non-alcoholic fatty liver disease) over the last few decades.
Researchers in a study led by Young-Mi Go and MSP faculty member, Dean Jones exposed mice to low levels of cadmium, so that the amounts of cadmium in their livers were comparable to those present in average middle age Americans, without tobacco or occupational exposure. They observed that cadmium-treated mice had more fat accumulation in the liver and elevated liver enzymes in their blood, compared with control mice with 10 times less cadmium.
Cadmium accumulates in the body over time. Tobacco smoke and the industrial workplace can be routes for cadmium exposure, but food is the major source for most non-smokers. Until the 1990s, most batteries were made with cadmium, and much cadmium production still goes into batteries. It is also found in paint and in corrosion-resistant steel.
Jones notes that population-based cadmium exposure continues to decrease, because fewer people are smoking. It was already known that high levels of cadmium exposure can lead to weakened bones and kidney failure, and cadmium is a known carcinogen. But the effects of lower levels of cadmium, which many people are exposed to, are still unclear.