As a chronic kidney disease (CKD) patient, have you been told by a healthcare professional to “eat less processed food?” It is often said but hard to follow as most of our foods are at least minimally, if not moderately, processed. Learn what researchers have discovered about the effects of processed foods on CKD.*

What are processed foods?

Processing is anything that changes food from its natural state. Processed food is divided into three categories: 

• Minimally-processed foods are still whole foods, where the vitamins and nutrients are still intact. Minimal processing can include drying, crushing, roasting, boiling, freezing, and pasteurization.
• Processed foods are created by adding salt, oil, sugar, and/or other substances
• Ultra-processed or highly processed foods have many added ingredients, including artificial colors and preservatives

Some examples of minimally-processed, processed, and ultra-processed foods include:

• Minimally-processed: shucked corn, dehydrated apples, freeze-dried potatoes
• Processed: canned corn, salted nuts, apple juice with added sugar, baked potato
• Ultra-processed: corn chips, apple pie, french fries, bread, donuts, potato chips

Oftentimes, when doctors and other healthcare professionals say to “avoid processed foods,” they are actually referring to ultra-processed foods. Research has linked ultra-processed food to some long-term diseases including CKD.

What has research discovered?

Between 1987-1989, researchers recruited 14,679 adults without CKD in the Atherosclerosis Risk in Communities Study, a long-term study that followed participants for decades. After participants completed a food frequency questionnaire twice during this time period, researchers assessed their intake of ultra-processed foods. 

In 2018, participants completed their final follow-up. Researchers compared all the participants’ food intake to the incidence and risk of CKD. Their findings include:

• Incidence for CKD was higher among participants who ate more ultra-processed foods compared to those who ate fewer ultra-processed foods
• Participants who ate more ultra-processed foods had a 24% higher risk of developing CKD 
• Participants who replaced one serving of ultra-processed food with a minimally- processed food reduced their risk of CKD by 6%. 

With the increased risk that ultra-processed foods pose to the kidneys and the body, replacing ultra-processed foods with minimally-processed foods may help to delay kidney disease and preserve overall health.

*Keenan, J. S. (2022, June 17). Higher ultra-processed food consumption correlates with higher risk for incident CKD. Healio. https://www.healio.com/news/nephrology/20220617/higher-ultraprocessed-food-consumption-correlates-with-higher-risk-for-incident-ckd