June 22, 2016 | 3 minute read

What do you think is a moderate amount of pizza? I would say 1-2 slices, but I can bet that my 20-year-old brother would say the whole pizza. Eating food in moderation has become a common piece of advice for weight-maintenance and weight-loss. Being a healthy weight is the most important thing you can do to prevent cancer, after not smoking, according to AICR research.

But, there is no set definition of moderation. It can vary from person to person, including the amount of food and how often to eat it. New research published in the journal Appetite looked at just that – how people define moderation and how that affects their eating habits.

Do you know the standard serving size of ice cream? Click to find out.

Three separate studies were completed to get to the bottom of this. First, a group of 89 female college students were shown a plate of 24 chocolate chip cookies. The majority of students defined a moderate amount as 3 cookies, which was more than the 2 cookies they believed they should eat.

The second study showed similar results, but used pictures of gummy candies instead of cookies. A moderate amount was about 11 gummy candies, whereas people think you should only eat 9 gummy candies. Initial findings also showed that how much you like a food would influence the amount you consider to be moderate. These participants were more varied than the first study, with 294 men and women and an average age of 37 years.

To further explore people’s food and drink preferences, a third study was carried out. Half of these participants were overweight or obese. An in-depth breakdown of participants’ intake of foods like ice cream and fast food showed that preference did affect their definition of moderation. In other words, if you really like pizza and eat a lot of it, your definition of moderation would generally be larger. And, the amount considered moderate would usually be bigger than the amount actually eaten. Importantly, these findings were the same no matter the persons’ weight.

These studies have a few limitations, including using self-reported intake and participants that differ from the general public. Also, these are done in a lab setting – it’s not real life. Nonetheless, the results suggest that moderation messages are unclear and personally defined amounts may actually lead to overeating.

Knowing the serving size can be really useful for weight-loss and weight-maintenance. This can be tricky, especially when it comes to foods that you really like. Use the Nutrition Facts label on food packages to help guide your choices. And take our quiz — below — to see how much you know about serving sizes, from broccoli to pizza.

Kaila Schoenberger is an Education & Communication Intern at AICR. She is an MPH/RD candidate from the University of Minnesota School of Public Health. She believes in preventing cancer by encouraging simple ways for people to eat well and be active.