If I could follow up on the research question, the evidence comes from three lines. The first is the association, which is not cause and effect. That is, if you actually monitor the sodium intake in a country and the average blood pressure, you can actually line them up. So there is a direct relationship.
The next level of evidence, which is more convincing, are the studies that were mentioned earlier. You take a population and actually reduce sodium in one group and keep the other group doing the same, and you can actually demonstrate that in fact there is reduction in the blood pressure.
The third aspect is the long-term consequence in terms of countries that have done this. The best example is Finland. But the challenge there is that there were many things done at the same time, so how much did the sodium reduction actually contribute to this?
The positive aspect from that is that in most of the studies that carried this out, the benefit you see in terms of heart disease is actually a lot more than you would expect from just blood pressure reduction alone. The fact that you are actually engaging the whole population in this type of effort has many other dividends that appear to pay off at the same time.
Those are the types of evidence. As we do this in Canada, we have to make sure we're actually reaching the goals we are looking for.