A documentary by Lee Fulkerson. Rated G.

Its superheroes are septuagenarian doctors and it’s filled with animated arterial plaque and statistical graphs, but Forks Over Knives is so persuasive that it somehow overcomes its occasional artlessness.

Put another way: when scientists have known for decades that a plant-based diet can pretty much prevent humankind’s biggest ailments—heart disease and cancer—but people continue to wolf back Quarter Pounders, can you really blame a movie for not being subtle?

The title refers to the concept that you can eat good food to avoid the knives of surgery. It’s pretty much the flip side to Morgan Spurlock’s more amusing Super Size Me: instead of focusing on how much damage fast food does to your body, Forks shows how much good a whole-foods, plant-based diet can do for it.

To make its case, the film centres on veteran scientists T. Colin Campbell and Caldwell Esselstyn Jr. and the mountains of research they’ve accumulated to back up their claim that meat and dairy are basically toxic.

Forks methodically takes on target after target, refuting ideas about osteoporosis and dispelling stereotypes of vegetarian weaklings.

Fulkerson spices things up with funky archival footage. And it’s telling when he tracks efforts by the U.S. Food and Drug Administration, the same agency that regulates and advocates for livestock and dairy farmers, to tell us what to eat.

Where the film falters is in interspersing case study after case study of sick, overweight Americans who reverse their conditions by taking on a diet that’s plant-only.

Still, the sheer quantity of information is hugely convincing. Watching it is like eating your spinach: not totally enjoyable but essential to your health.

Watch the trailer for Forks Over Knives.