It's already required for them to label it, but there's several problems with that solution that we've been dealing with since that was mandated.
For one, if you have less than 0.5 grams per serving in your product you can label it as 0 grams of trans fat. This is a problem because serving size is arbitrarily determined by the producer of the product, which with a small enough portion size can still leave trans fat in significant portions while labeling it at zero grams. Other tricks exist like using different types of oils (trans and regular oils) in different manufacturing plants and calculating the average amount over all locations the product is produced. The other issue with this is that even relatively small amounts (relative to how much food we consume) can be very detrimental to your health.
The other issue is related to the first and that even consumers that want to avoid trans fats can have trouble doing so if they don't realize the first point I made, and the only way to avoid that is to scan every ingredients list for partially hydrogenated oils.
Oh I agree that would definitely have a good effect for increasing knowledge of what one is actually consuming, but I think uncertainty comes into play at some point.
In any event I don't think that banning trans fat was the only way to solve the problems I listed. Though I do detest trans fat and it annoys me when I can't consume or purchase a product because I noticed there is a non-trivial amount of trans fat in it. In this way, banning trans fats is definitely a convenient solution for me and I don't see many downsides to supporting it.
For one, if you have less than 0.5 grams per serving in your product you can label it as 0 grams of trans fat. This is a problem because serving size is arbitrarily determined by the producer of the product, which with a small enough portion size can still leave trans fat in significant portions while labeling it at zero grams. Other tricks exist like using different types of oils (trans and regular oils) in different manufacturing plants and calculating the average amount over all locations the product is produced. The other issue with this is that even relatively small amounts (relative to how much food we consume) can be very detrimental to your health.
The other issue is related to the first and that even consumers that want to avoid trans fats can have trouble doing so if they don't realize the first point I made, and the only way to avoid that is to scan every ingredients list for partially hydrogenated oils.