Actually my dentist (Dr. el-essawy in London) told me to completely avoid during the detox any garlic/onions/leek (unless biodynamically grown), eggs and chicken meat as all these contain high concentrations of mercury from the fertilizers in the soil (yes even organic ones as the natural fertilisers are usually animal escrements that have mercury in them too).

These contain all high concentrrations as they strongly absorb it from the ground the same way they would do in our bodies.

This is not just a theory, he has a mercury vapour analyzer in his practice with which he has measured loads of samples over the years and he actively encourages his patients to bring along food samples for testing.