Food, like everything around us, is made up of chemicals.
Around 500 years ago a man named Paracelsus famously said “the dose makes the poison". Meaning for most chemicals, there is a level of exposure below which there are no harmful effects.
In foods, these levels are usually known an 'acceptable daily intake' or more simply put, ADI. An ADI is the amount that you can consume every day for your entire life – safely.
Since the first ADI was set some 60 years ago, there have been no cases of adverse effects in the general population associated with exposure below an ADI.
ADIs are set by Joint Expert Committee on Food Additives, and also by...us.
So how are they set?
From experimental studies in animals and humans.
We take the lowest dose at where no effects are seen, then apply two safety factors:
- 10-fold to account for potential differences between animals and humans; and
- an additional 10-fold to account for any differences in human sensitivity
Meaning an ADI is usually 100 times less than the maximum dose at which no effects are seen in animal studies.
And because the chemical is tested in animals at different life stages it is also protective of humans at different life stages.
However there can be some cases of extreme sensitivity in the population, such as people with genetic diseases like phenylketonuria (PKU). This is why additional protection such as mandatory labelling is sometimes required.
ADIs are highly conservative and ensure we have a safe food supply here in Australia and New Zealand.