A lot of people believe that Japanese food is healthier than other food, but I don't necessarily believe that is true. I think that Japanese people tend to eat less than people in other countries and that they make better food choices with an eye toward a good nutritional balance, but looking at the overall options for eating, Japanese cuisine doesn't really stack up better than many other countries food. That's okay. No food culture needs to be a paragon and they all have strengths and weaknesses. One of the strengths is that there is less sugar. On the other hand, there is generally more fat in food that contains fats (such as processed food, but also tempura, tonkatsu, pasta sauces, and even certain stews and soups). (And if you think that Japanese folks are sitting down to nosh on sushi, sashimi and broiled fish every night, then you clearly haven't been paying attention.) The high fat content would make the calorie content of something which seemed pretty innocuous and bland into a gut expander. A lot of foreigners eat the food thinking it's probably not so fattening because it's not so sweet. They are often wrong.
Japanese tastes run toward things which are creamy and that carries a calorie price tag that I won't miss.