There is a difference between claims and logos. One on hand, you have logos, which should be regulated, in my opinion. For example, the “Health Check” logo is currently overseen by the Heart and Stroke Foundation of Canada, an independent organization that authorizes companies to put the logo on their products. I think when you have a situation like this, with an independent body authorizing the use of the logo, that is the way to go. Where problems arise is when companies are the ones putting the logo on their products, because each of them can establish an arbitrary set of criteria for using that logo. We should do more to control the use of logos and favour those issued by independent companies and organizations.
On the other hand, you have claims, which should be made based on the composition of the product as a whole, as is the case when something is labelled as “trans fat free”, a declaration requiring manufacturers to take into account the saturated fat content, as well. So a number of factors related to the composition of the food product need to be taken into account before any claim can be made about the product.