New research published in Neurology suggests that there is a link between cadmium exposure and memory problems, with a higher impact on cognitive ability in white individuals. Cadmium is a toxic heavy metal found in polluted air, cigarette smoke, and food. The study examined the urine of 2,172 people, finding a significant positive association of cadmium in the urine of white participants with cognitive issues. Over a 10-year period, 195 people developed cognitive impairment, with white participants with higher concentrations of cadmium in their urine having a doubled risk of cognitive impairment compared to those with lower concentrations. There was no such association found in Black participants.
Cadmium, a known carcinogen that can contribute to the development of dementia, is released into the environment through industrial and agricultural activities. Its effects on the brain and central nervous system are widespread, disrupting calcium levels in the brain and activating pathways associated with inflammation and neural cell death. It can accumulate in the brain over time, causing oxidative stress, interfering with metabolic pathways, and leading to neuronal damage and cell death. Smoking appears to provide the most exposure to cadmium for white individuals, potentially explaining the racial discrepancy in cognitive decline observed in the study.
Even in small amounts, cadmium is toxic for humans, as it can penetrate the blood-brain barrier and stay in the brain, accumulating over a person’s lifetime. The properties of cadmium make it particularly insidious, causing oxidative stress, interfering with metabolic pathways, and potentially leading to reduced neurogenesis. Exposure to cadmium primarily occurs through the food supply, with socioeconomic factors playing a role in determining which populations are exposed to higher levels. In the U.S., exposure tends to be higher in industrialized regions, areas with historical heavy metal contamination, and regions with higher pollution levels.
Further research is needed to establish a more solid cause-and-effect relationship between cadmium exposure and cognitive impairment in different populations. While regions with higher environmental cadmium levels have shown higher rates of dementia, establishing a direct causal link requires more data. It is possible that communities with higher cadmium exposure, such as those near industrial areas or with higher smoking rates, may have an increased risk of cognitive problems over time. More research is needed to definitively establish a clear connection between cadmium exposure and dementia rates in specific regions.
