Right now, Post explains, the agency’s main message to Americans is to limit overall calorie intake, irrespective of the source. “We’re finding that messages to consumers need to be short and simple and to the point,” he says. Another issue facing regulatory agencies, notes Harvard’s Stampfer, is that “the sugared beverage industry is lobbying very hard and trying to cast doubt on all these studies.”
The medical studies about what food to eat to remain healthy can be confusing  but some details are not really in doubt. So while the exact dangers of processed carbohydrates, fat, excess calories and high fructose corn syrup may be in question their is no doubt we, in the USA, are not as healthy as we should be . And food is a significant part of the problem. Eat food, not too much, mostly plants  and get enough exercise is good advice.
Related: Statistical Errors in Medical Studies  – Researchers Find High-Fructose Corn Syrup Results in More Weight Gain  – The Calorie Delusion  – Obesity Epidemic Explained, Kind Of  – Active Amish Avoid Obesity