Minimizing overly processed foods in your diet is a crucial step in preventing chronic inflammation and various inflammation-related chronic diseases. However, discerning which foods qualify as “processed” can be tricky. After all, certain processing methods can actually enhance food’s health benefits.
“When done correctly, processing can preserve the nutritional value of foods or increase their availability, especially during off-seasons when local produce is scarce. Processing can also improve food safety, as seen with pasteurized milk, which eliminates harmful bacteria. Furthermore, fermentation can enhance the healthfulness of foods like yogurt,” explains Dr. Walter Willett, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health.
So, when does processing become detrimental, and which processed foods should we avoid? Here’s what you need to know about How Do You Know If Food Is Processed.
Understanding Processed Foods
Processed foods are defined as those that have been altered from their original, natural state. This can range from simple chopping and freezing (like vegetables) to removing inedible parts (like nut shells). These minimal changes are considered minimal processing.
The next level involves adding a few ingredients. Examples include simple crackers made with wheat, oil, and salt, freshly baked bread, or canned vegetables preserved in water and salt.
Foods subjected to more extensive processing are categorized as “ultra-processed.” According to Dr. Willett, “Ultra-processing often obscures the original ingredients, and these foods frequently contain additives such as preservatives, oil, sugar, salt, coloring, and flavoring. This is essentially what we consider junk food.”
Common examples of ultra-processed foods include hot dogs, deli meats (see “The Dangers of Processed Meat”), cheese puffs, doughnuts, frozen pizza, white bread, cookies, microwaveable dinners, and soda.
photo of a woman in a supermarket standing behind her shopping cart looking at a food label in the refrigerated section, checking if the food is processed
The Dangers of Processed Meat
Processed meats rank among the least healthy food choices. Examples include bacon, sausage, ham, hot dogs, salami, and deli meats like roast beef or turkey. These products are typically high in salt, unhealthy saturated fats, nitrates, nitrites, and various chemical additives like coloring, flavoring, and preservatives.
Consuming large quantities of processed meat is linked to increased risks of cardiovascular disease and colorectal cancer. For instance, a 2019 study published in the International Journal of Epidemiology, involving nearly 500,000 participants, revealed that individuals consuming red or processed meat four or more times weekly had a 20% higher risk of developing colorectal cancer over a five-year period compared to those consuming it less than twice a week.
The International Agency for Research on Cancer, a division of the World Health Organization, classifies processed meat as a carcinogen (a substance capable of causing cancer) for colorectal cancer in humans.
Health Risks Associated with Ultra-Processed Foods
When health experts caution against processed foods, they generally refer to ultra-processed options. These foods pose several health risks.
“Processing often diminishes the nutritional value of foods, such as when refining whole grains,” notes Dr. Willett. “It can also generate harmful molecules like trans fats or introduce excessive amounts of salt and sugar, which are detrimental.”
High consumption of ultra-processed foods is associated with an increased risk of chronic inflammation, various chronic diseases (including heart disease, diabetes, inflammatory bowel disease, obesity, and cancer), and premature death.
For example, a 2019 study in The BMJ, which tracked over 105,000 individuals for five years, found that for every 10% increase in ultra-processed food consumption, the risk of heart attack or stroke increased by 12%. Another 2019 BMJ study, involving nearly 20,000 participants followed for an average of 10 years, showed that those consuming more than four servings of ultra-processed foods daily had a 62% higher risk of death during the study (from any cause) compared to those consuming two servings per day.
Identifying Ultra-Processed Foods: How Do You Know If Food Is Processed?
Generally, ultra-processed foods are easy to identify – they typically have lengthy ingredient lists. They are commonly found on store shelves, in freezers, refrigerated sections, delis, or bakeries. Common examples include packaged, ready-to-eat entrees or meals, prepared side dishes, snacks, and sweets like cookies and cakes.
However, some ultra-processed foods may deceptively appear healthy. This is often the case with ultra-processed versions of fruit-flavored yogurts, refrigerated soups, refrigerated pastas (like chicken tortellini), granola bars, juices, breakfast cereals, frozen yogurt, low-fat salad dressings, condiments, butter substitutes, low-salt crackers, or nut butters.
So, how can you tell if something is ultra-processed? The key is to scrutinize the ingredient list on the food label. If you encounter numerous ingredients, including chemicals and unfamiliar terms, the product is likely ultra-processed. It’s best to choose alternatives with the shortest, most recognizable ingredient lists.
Occasional Indulgence: Is It Ever Okay to “Cheat”?
Avoiding ultra-processed foods entirely can seem challenging, particularly when you’re on the go or craving a ready-to-eat muffin, a deli sandwich, or a homemade ragù with chicken sausage. Is it acceptable to occasionally bend the rules if you maintain a generally healthy diet?
“Almost anything is okay if you break the rules just once a month,” says Dr. Willett. “But keep an eye on the other ingredients. For example, the ragù could be fine if the salt is kept below 200 milligrams [mg] per serving.”
Other guidelines to consider: Maintain a total daily salt intake below 2,300 mg, unless your doctor advises a lower limit. Limit saturated fat to no more than 10% of your daily calories, and restrict added sugars to no more than 24 grams per day for women and 36 grams per day for men.
Whenever possible, prioritize whole, unprocessed foods as part of a plant-based diet that includes vegetables, legumes, fruits, whole grains, nuts, and seeds.
And remember, “Just because foods are unprocessed, it does not mean that they’re healthy,” Dr. Willett emphasizes. “A diet based on red meat, milk, and potatoes is unprocessed but far from optimal.” A balanced and informed approach is key to a healthy diet.
