Although absorption from food is low (3-5%), retention in the kidney and liver is significant, with a very long half-life of between 10-30 years. Cadmium is listed as a human carcinogen by the International Agency for Research on Cancer (IARC).

Recently, a systematic review and meta-analysis has been published, which summarizes the results of publications regarding the positive association between elevated cadmium concentrations and both type 2 diabetes and prediabetes from 1992 to 2022. They included studies that assessed cadmium exposure through biomarker levels; examined type 2 diabetes or prediabetes among outcomes; reported effect estimates for cadmium exposure for meta-analysis only.

The dose-response meta-analysis showed a linear positive association with diabetes risk for increasing levels of urinary cadmium, a positive association for the highest cadmium blood concentrations (above 2 µg/L), and a monotonic linear increase in risk in studies that measured urinary cadmium concentrations. 

Regarding prediabetes, a positive association has been found for cadmium concentrations in both urine and blood when comparing the highest versus lowest exposure categories. They also found consistent epidemiological evidence that higher cadmium exposure was associated with increased risks of both diabetes and prediabetes. Diabetes risk increased linearly in studies measuring urinary cadmium concentrations, while disease risk increased only at the highest exposure levels when assessed measuring blood concentrations.