First came An Inconvenient Truth. Then Fast Food Nation. Then Blackfish.
Each showed the power of critically acclaimed, successful documentaries to alter perceptions about controversial issues ranging from global warming to mistreatment of animals in captivity and the behaviour of food industry giants.
Now comes Fed Up, a film that looks at the global problem of surging human obesity rates and obesity-related diseases.
The film, produced by Laurie David and narrated by TV journalist Katie Couric, seeks to challenge decades of misconception and food industry-sponsored misinformation about diet and exercise, good and bad calories, fat genes and lifestyle.
When it comes to obesity, fat may not be our friend but it's not the enemy that sugar is, says the film's scientific consultant Robert Lustig, a neuroendocrinologist, author and president of the Institute for Responsible Nutrition.
It is a view that is gathering support from doctors.
A US Government study recently found that 17 per cent of children and young people aged between 2 and 19 are considered obese. Another predicted that today's American children will lead shorter lives than their parents.
Laurie David, who made the climate change film An Inconvenient Truth, calls that statistic "sobering and tragic".
According to Lustig, however, neither obesity nor fat is the issue.
"The food industry wants you to focus on three falsehoods that keep it from facing issues of culpability. One, it's about obesity. Two, a calorie is a calorie. Three, it's about personal responsibility," he said.
"If obesity was the issue, metabolic illnesses that typically show up in the obese would not be showing up at rates found in the normal-weight population.
"More than half the populations of the US and UK are experiencing effects normally associated with obesity. If more than half the population has problems, it can't be a behaviour issue. It must be an exposure problem. And that exposure is to sugar."
The film claims fast-food chains and the makers of processed foods have added more sugar to "low fat" foods to make them more palatable. It says big business is poisoning us with food marketed under the guise of health benefits. Early-onset diabetes, a condition associated with exposure to cane sugar and corn syrup, was virtually unknown a few years ago. If current rates continue, one in three Americans will have diabetes by 2050.
Efforts to curb the sugar industry have largely failed. In 2003 the Bush Administration threatened to withhold funding to the World Health Organisation if it published nutritional guidelines advocating that no more than 10 per cent of calories daily should come from sugar.
Moreover, Washington has sweetened the profits of the manufacturers of corn-based sweeteners by awarding billions of dollars in trade subsidies.
The film-makers say it is not in the interest of food, beverage or pharmaceutical companies to reduce sugar content. "It's too profitable," says Lustig.
The pharmaceutical industry talks of diabetes treatment, not prevention. "The food industry makes a disease and the pharmaceutical industry treats it.
"They make out like bandits while the rest of us are being taken to the cleaners."