Because new potatoes have more moisture and a lower starch content, they will absorb less of the cooking water, as well as less of the mayonnaise or vinaigrette dressing. Therefore, new potatoes will be less likely to break when the salad is mixed and served. Just as important, because it is not so thoroughly absorbed, the sauce has not as much opportunity to overpower the more delicate flavor of the potatoes. When less of the sauce is absorbed, we consume less calories.
** Asian Recipes