Manipulation of serving sizes is a serious problem. At the end of the day consumers need to use common sense and look for nutritionally rich foods and not hide in ’100 calorie’ claims of products with empty calories – ie chips, soda, etc. But it would help society if reasonable standards were enforced so that unscrupulous food companies wouldn’t post silly claims about calorie count or sodium content in the front of the labels, that only a careful observer would realize assumes consumption of a fraction of the product.
This article describes the FDA’s efforts to zero in on the problem. But it doesn’t mention what most of the world – except the US – does. They require every product to list nutritional impact per 100 grams. I used to think that is confusing because you don’t necessarily consume 100 grams of that product. But it creates a benchmark that is easy to compare. And it doesn’t have to exclude an additional column for nutritional facts per portion.