Small changes in diet could help you live healthier, more sustainably: Study

Eating a hot dog could shave 36 minutes off your life, while choosing to eat a serving of nuts instead could help you gain 26 minutes, according to a University of Michigan study.

The findings, published in the journal Nature Food, evaluated more than 5,800 foods, ranking them by their nutritional disease burden to humans, and their impact on the environment.

It found that substituting 10 percent of daily caloric intake from beef and processed meats for a mix of fruits, vegetables, nuts, legumes and select seafood could reduce your dietary carbon footprint by one-third and allow people to gain 48 minutes of healthy minutes each day.

“Generally, dietary recommendations lack specific and actionable direction to motivate people to change their behavior, and rarely do dietary recommendations address environmental impacts,” said Katerina Stylianou, who did the research as a doctoral candidate and postdoctoral fellow in the Department of Environmental Health Sciences at U-M’s School of Public Health. She currently works as the Director of Public Health Information and Data Strategy at the Detroit Health Department.

This work is based on a new epidemiology-based nutritional index, the Health Nutritional Index, which the investigators developed in collaboration with nutritionist Victor Fulgoni III from Nutrition Impact LLC. HENI calculates the net beneficial or detrimental health burden in minutes of healthy life associated with a serving of food consumed.

Measuring impact on health

The index is an adaptation of the Global Burden of Disease in which disease mortality and morbidity are associated with a single food choice of an individual.

For HENI, researchers used 15 dietary risk factors and disease burden estimates from the GBD and combined them with the nutrition profiles of foods consumed in the United States, based on the What We Eat in America database of the National Health and Nutrition Examination Survey.

Foods with positive scores add healthy minutes of life, while foods with negative scores are associated with health outcomes that can be detrimental for human health.

The environmental impact on what we eat

To evaluate the environmental impact of foods, the researchers utilized IMPACT World+, a method to assess the life cycle impact of foods (production, processing, manufacturing, preparation/cooking, consumption, waste), and assessments for water use and damage to health.

Finally, the researchers classified foods into three color zones: green, yellow and red, based on their combined nutritional and environmental performances.

The green zone represents foods that are recommended to increase in one’s diet and contains foods that are both nutritionally beneficial and have low environmental impacts. Foods in this zone are predominantly nuts, fruits, field-grown vegetables, legumes, whole grains and some seafood.

The red zone includes foods that have either considerable nutritional or environmental impacts and should be reduced or avoided in one’s diet. Nutritional impacts were primarily driven by processed meats, and climate and most other environmental impacts driven by beef and pork, lamb and processed meats.

The researchers acknowledge that the range of all indicators varies substantially and also point out that nutritionally beneficial foods might not always generate the lowest environmental impacts and vice versa.

“Although we find that plant-based foods generally perform better, there are considerable variations within both plant-based and animal-based foods,” Stylianou said.