An interesting article on the subject:
Nutri-Score, a boon for the food industry
Far from compelling manufacturers to offer less processed products, the Nutri-Score labeling reinforces them in their bad practices.
Promoters of Nutri-Score present their labeling by letter and traffic light as a way to direct the consumer towards better products and at the same time, to force manufacturers to formulate healthier products.
But if you look closely, you may be afraid that none of these objectives will be achieved.
As researcher Anthony Fardet says, the criteria on which Nutri-Score is based belong to the "old world": the food is reduced to a sum of nutrients - calorie content, saturated fat, sugar, salt ... - which alone would decide his interest or not for health. This seemingly rational approach has failed everywhere it has been implemented.
To transpose it in the form of green, orange, red colored pellets on the food is doomed to the same failure.
https://www.thierrysouccar.com/blog/le-nutri-score-une-aubaine-pour-lindustrie-agro-alimentaire
Or how to turn a good idea into a non-event ...