If you want your persuasive essay to actually persuade your reader to your point of view, you need a logical, coherent argument backed up by relevant, persuasive evidence. Your evidence is the data, facts, and ideas that support your position.

A photograph of a “Whole Foods Market” sign outside of the store in Austin, TX

Source: Whole Foods HQ Austin,
@MSG, Flickr

A photograph of a stack of yogurt containers

Source: yogurt, Jason McKim, Flickr

A Photograph of a woman eating yogurt. She is smiling and holding her spoon up tp the camera.

Source: YOGURT!!, Jes and Colin, Flickr

Think about the way food is marketed today. More and more food manufacturers are touting the health benefits of the foods they sell. People who care about eating healthy foods prefer to base their choices on evidence that shows that what they are eating is actually good for them.

For example, let's look at advertising for yogurt. A 2010 study by the Journal of Clinical Nutrition found that people who consumed 580 mg of dairy calcium per day lost more weight than people who consumed only 150 mg of dairy calcium. This evidence has been widely used by dairy companies who want to appeal to customers interested in losing weight. Providing evidence that suggests that yogurt is good for you is much more likely to persuade the consumer than simply saying, “Our yogurt is good for you. Trust us.”

In this lesson, we will discuss ways to review the facts and data you provide. We will also look at the sources for these facts and data.