Ultra-processed foods are a double threat: they damage your body and accelerate climate change. More than half of the calories adults consume daily come from ultra-processed products, yet these heavily modified foods contribute significantly to both the obesity epidemic and environmental degradation . The problem isn't just individual eating habits; it's a systemic issue rooted in food access inequality and how modern food systems operate.

How Do Food Systems Contribute to Climate Change?

The connection between what you eat and planetary health is more direct than most people realize. Food systems produce approximately 30% of global greenhouse gas emissions, according to nutrition experts at George Mason University . These emissions come from multiple stages of food production and distribution.

• Land Use: Agricultural expansion requires clearing forests and natural habitats, reducing the planet's ability to absorb carbon dioxide.
• Livestock Production: Raising animals for food generates methane and other potent greenhouse gases, though the issue is overconsumption rather than the inclusion of animal foods themselves.
• Agricultural Practices: Conventional farming methods, including pesticide and fertilizer use, release emissions and degrade soil health.
• Transportation: Moving food from farms to processing facilities to stores requires fuel-intensive logistics.
• Modern Food Processing: The industrial processing that creates ultra-processed foods requires significant energy and generates waste.

"Food systems produce approximately 30% of global greenhouse gas emissions, which experts agree are responsible for climate change. Land use, livestock production, agricultural practices, transportation, and modern food processing systems all contribute broad adverse effects on the environment," explained Lawrence J. Cheskin, MD, a physician specializing in dietary behavior change at George Mason University.

Lawrence J. Cheskin, MD, George Mason University College of Public Health

Why Is Food Access, Not Just Personal Choice, the Real Problem?

The obesity epidemic isn't simply a matter of willpower or individual eating decisions. Overweight and obesity are strongly linked to social vulnerability factors, including lower socioeconomic status, lower educational attainment, and limited access to nutritious foods . Many communities are food deserts, where fresh fruits and vegetables are either unavailable or unaffordable for low-income families. Ultra-processed foods, which are cheap and shelf-stable, often become the only realistic option.

This creates a vicious cycle: people in vulnerable communities consume more ultra-processed foods because that's what's available and affordable, which drives demand for these products. Manufacturers continue producing them in massive quantities, which requires intensive agricultural and processing systems that emit more greenhouse gases. Meanwhile, the health consequences of ultra-processed food consumption accumulate in the same communities with the least access to healthcare.

"Overweight and obesity are influenced by more than individual eating behaviors. Indicators of social vulnerability, including lower socioeconomic status, lower educational attainment, and younger age are strongly linked with unhealthy food consumption. Many communities are food deserts, where access to nutritious foods is limited," noted Cheskin.

Lawrence J. Cheskin, MD, George Mason University College of Public Health

What Exactly Are Ultra-Processed Foods?

Ultra-processed foods are products that have been heavily altered from their natural state and typically contain ingredients you wouldn't find in a home kitchen . These foods are usually high in sodium, added sugars, and unhealthy fats, and they contain long lists of additives like colorings, emulsifiers, and stabilizers. Common examples include soda, energy drinks, breakfast cereals, hot dogs, candy bars, chips, and canned soup.

The key difference between ultra-processed and minimally processed foods matters for both health and the environment. Minimally processed foods like frozen vegetables, prepared salad greens, milk, and eggs have been cleaned, cut, frozen, or cooked with little to no additives. Processed foods start as whole foods but have only a few added ingredients such as salt, oil, or sugar. These categories are still recognizable as the original food, whereas ultra-processed products often bear little resemblance to their source ingredients.

How to Reduce Ultra-Processed Food Consumption

• Read Ingredient Lists Carefully: Choose foods with fewer than five ingredients on the label, and avoid products with unfamiliar additives. If you can't recognize an ingredient, it's likely a sign the food is ultra-processed.
• Shop the Perimeter: Focus your grocery shopping on the outer edges of the store where fresh produce, lean proteins, nuts, seeds, and whole grains are typically located. Avoid the center aisles where ultra-processed products dominate.
• Make Simple Swaps: Replace soda with flavored water, chips with popcorn, or processed cereal bars with single-ingredient peanut butter on whole wheat bread. These substitutions reduce ultra-processed food intake without requiring dramatic dietary overhauls.
• Cook from Scratch or Batch Cook: Preparing meals at home minimizes impulsive, convenient choices and gives you control over ingredients. Batch cooking on weekends can make healthy eating more convenient during busy weekdays.
• Introduce Changes Gradually: Sustainable dietary change happens incrementally, not overnight. Start with one or two swaps and build from there as new habits solidify.

What About Plant-Based Alternatives?

Many people assume that switching to plant-based diets automatically solves both health and environmental problems. However, the reality is more nuanced. The issue isn't animal-based foods themselves, but their overconsumption, which drives intensive production systems that harm the environment . Many plant-based products, including plant milks, plant-based meat alternatives, energy bars, and snack foods, are highly processed and can be more energy-dense than animal-sourced foods.

"The issue is not the inclusion of animal-based foods in the diet per se, but their overconsumption, which drives intensive production systems that degrade the environment," explained Raedeh Basiri, PhD, RDN, a registered dietitian and assistant professor at George Mason University.

Raedeh Basiri, PhD, RDN, George Mason University College of Public Health

Basiri also cautioned that major dietary shifts toward plant-based eating carry potential risks for vulnerable populations. Children, older adults, pregnant and lactating women, and individuals with chronic diseases may struggle to meet their nutritional needs if animal-sourced foods are substantially reduced or eliminated, since plants are limited sources of certain essential nutrients. Until stronger evidence exists about large-scale dietary transitions, experts recommend emphasizing minimally processed options across all food categories rather than assuming climate benefits automatically translate to health benefits.

What Solutions Address Both Obesity and Climate Change?

Fixing these interconnected crises requires systemic change, not just individual behavior modification. Efforts to reduce ultra-processed food consumption must be accompanied by strategies that increase the availability and affordability of healthy foods, particularly for low-income populations . Programs like Food is Medicine, which emphasize access to and education about nutritious foods, demonstrate how multi-approach strategies can benefit at-risk communities.

Emerging technologies also show promise. Continuous glucose monitoring, which allows individuals to see the immediate effects of their food choices on blood sugar levels, may motivate healthier eating decisions. Expanding these approaches to include broader lifestyle supports, such as mental health services and opportunities for physical activity, could further strengthen obesity prevention efforts while also reducing the environmental impact of food systems.

The bottom line is clear: your grocery choices matter not just for your personal health, but for the health of the planet and vulnerable communities. By understanding what's in the foods you eat and choosing less processed options whenever possible, you contribute to solutions for both the obesity epidemic and climate change.