[GUEST BLOG] Deep Dive into Research on the Power of Customizable Portions to Reduce Plate Waste

In a study published earlier this year—”Customizable Portions: A Cost-Conscious Approach to Reducing Plate Waste”—researchers found that portion customization is a largely untapped yet extremely effective way to address the number one cause of food waste in restaurants and foodservice settings: plate waste (food that’s sold but not actually eaten). The study was supported by ReFED and conducted by Georgetown University’s Portion Balance Coalition, the Earth Commons Institute, Georgetown’s Business for Impact School, and the Menus of Change University Research Collaborative (MCURC), which is co-founded and jointly led by R&DE Stanford Dining, Hospitality & Auxiliaries, Stanford Prevention Research Center, and the Culinary Institute of America. In this project, researchers studied front-of-house (FOH) food waste through expert interviews and industry surveys, waste audits, plate-level measurement, and menu analysis. Despite few operators embracing flexible portions as a menu strategy, consumer data indicates a strong desire for greater control over portion sizes when eating away from home. This stems from a convergence of trends: heightened cost-consciousness amid a widespread affordability crisis, growing interest in GLP-1 medications, a continued preference for snacking, and the evolving meaning of “customization” in the consumer’s mind—truly optimizing their food experiences whenever and however possible. This means that customizable portions offer untapped potential for foodservice operators to enhance profitability, support sustainability goals, and improve customer satisfaction.

We at the Menus of Change University Research Collaborative (MCURC) have been studying food waste reduction for years. The MCURC is a global network of over 600 members across nearly 100 colleges and universities that work together to advance healthy, sustainable, delicious food choices by using campus dining halls as living laboratories for behavior change. Food waste reduction and prevention is one of three focus areas of our research agenda, which also includes plant-forward menus and food literacy.

The extraordinary collaboration of the “Customizable Portions” project built upon other research conducted with ReFED in recent years. In 2025, the R&DE Stanford Food Institute, a signatory of the U.S. Food Waste Pact (USFWP), partnered with the MCURC, the Pacific Coast Food Waste Commitment, and the USFWP (which is led by ReFED and the World Wildlife Fund) on "Empowering Staff in Foodservice: A FoodWISE Approach to Reducing Food Waste,” a project that engaged over 200 employees across 10 foodservice sites to demonstrate the power of engaging frontline staff in reducing back-of-house food waste. In 2023-2024, MCURC partnered with ReFED on “Repurpose with a Purpose,” a multi-pronged research project, operational toolkit, and recipe collection that illustrated the cost savings, positive environmental impacts, and benefits for employee job satisfaction of repurposing surplus food in campus dining settings.

“This is exactly the kind of research we aim to put into practice through MCURC, and in collaboration with ReFED, to support the broader industry: actionable insights that help foodservice businesses thrive while advancing healthy, sustainable menus and operations,” said Abby Fammartino, Director of Health & Sustainability Programs and Research at The Center for Food & Beverage Leadership at the Culinary Institute of America, and Co-Director of the MCURC. “Giving guests more choice in portion size can help operators reduce costs, make better use of food and resources, and meet growing demand for meals that fit individual appetites—potentially giving customers more reasons to return.”

Our ideal projects are those that look at the intersection of both human and planetary health, and there are few topics that hit that bullseye as much as portion size does. This most recent study on portion sizes represented a particularly exciting step in our 14-year research journey because it’s one of the first times we closely investigated operational strategies to reduce front-of-house food waste, and it became clear from the research that oversized portions, complex menus, and diner behavior are among the greatest places to intervene. One thing that really surprised the research team was that most operators surveyed did not think front-of-house waste was a problem, making it hard to recruit sites for a portion customization trial. Instead, we pivoted our research to make plate waste visible in order to build the case for customizable portions. We hope to test portion options in the next phase of this research, building on the findings thus far and going further into the benefits of customization as a food waste and cost-saving solution.

Based on expert interviews, analysis of dozens of menus, a survey, and in-house food waste audits at four foodservice locations, these were the key takeaways and top recommendations for foodservice operators across both noncommercial segments (institutional settings like campus dining, corporate dining, and hospital foodservice) and commercial segments (fast-casual, quick-serve, and full-service restaurants):

• Set food waste reduction targets. These were found to be critical to successful waste reduction.

• Track FOH food waste. Integrating food-waste data into portion decisions can help understand consumer behavior and provide operational insights and saving opportunities.

• Adapt menus to appeal to evolving customer preferences. ReFED’s “2026 From Plate to Profit” report found that 59% of consumers say they would be more likely to frequent restaurants offering flexible portion sizes, and nearly half are willing to pay a little more for right-sized meals that better fit their appetite.

• Understand what menu items end up in the trash. More indulgent menu items, starches, and default sides were found to dominate plate waste, showing the opportunity to adjust menus to reflect these signals from diners.

• Embed food waste reduction in employee-customer interactions. Train staff to engage diners and gather valuable feedback that can reduce waste and costs, and improve diner satisfaction.

• Market portion and meal changes to highlight customer satisfaction. Offering flexible portions won’t be a one-size-fits-all strategy, so tailored approaches are essential, and ultimately it comes down to knowing your audience and your operation, but regardless, frame the menu structure as an opportunity and a win-win for everyone involved: doing so can drive repeat customers and ensure that both operations and businesses are sustainable over the long run.

Where we go from here

Going forward, we aim to raise awareness about the value of measuring plate waste and conduct future research that builds upon these findings through more waste audits across a wider range of restaurant types and customer demographics, continuing to test portion options in real-world settings, and pairing these pilots with customer satisfaction surveys. Armed with those insights, operators will be able to refine and highly target their portion optimization strategies to the greatest outcomes.

But there’s no time to waste, and this report provides more than a starting point—it offers a roadmap for operators across the industry. We were stunned to learn that only 1 in 5 surveyed restaurants measure plate waste. Operators shouldn’t merely accept front-of-house waste as a given—they should take matters into their own hands, to understand it, recognize its greatest drivers, and reap the rewards of being able to predict and therefore minimize it over time. The cost savings can be tremendous. And there has never been a more ripe time for industry leaders to leverage portion design as a smart business strategy: Food costs are a pressing stresspoint for most every operation, at the same moment that consumer demand is shifting to greater control over portions due to evolving definitions of “value” and health trends such as GLP-1 use. Restaurants that get ahead by offering flexible portions stand to take the upper hand on profitability, customer satisfaction, and environmental impact.

For more information, please visit moccollaborative.org.

The views and opinions expressed in this guest blog are those of the author and do not necessarily reflect those of ReFED.

Author Bio: Sophie Egan, MPH is an internationally recognized leader at the intersection of food, health, and climate. Her work accelerates solutions for food systems change, which she does through a portfolio of leadership roles: Senior Advisor to the R&DE Stanford Food Institute, Co-Director of the Menus of Change University Research Collaborative, Director of Strategy for BITE: Building Impact Through Eaters, and Strategic Advisor for Nutrition and Health to the International Fresh Produce Association and Foundation for Fresh Produce. She is also a contributor to The New York Times Health section and Co-Founder of Climate Kitchen. Previously, Sophie served as Director of Health and Sustainability Leadership for The Culinary Institute of America’s Strategic Initiatives Group.