Whole Foods vs. Processed Foods


Whole foods are foods that have not been processed or refined. In most cases, they do not contain added sugar, fat, or salt. Examples of whole foods are whole, unpolished grains (grains containing the bran, endosperm, and germ of the original grain); nonhomogenized dairy products; unprocessed meat, poultry, and fish; and fruits, nuts and seeds, legumes, and vegetables. “Whole foods” should not be confused with “organic” foods, which are foods produced without the use of pesticides, fertilizers, hormones, antibiotics, other chemicals, or genetically modified seeds. Whole foods are not necessarily organic in origin, and organic foods can include processed foods.

Fresh fruits and vegetables are examples of whole foods.

Fresh fruits and vegetables are examples of whole foods.

Processed foods include all food products that have been altered in some way to either turn them into food, extend their shelf life, or prepare them for human or animal consumption. Processed foods can include foods prepared at home as well as in commercial food processing plants. Cat or dog foods and feed mixtures for farm animals are considered processed foods, as are Meals Ready-to-Eat (MREs) for combat troops and specialized foods prepared for mountain climbers, explorers, astronauts, and others working or traveling in environments where cooking would be difficult or impossible.

Convenience foods are a specific category of processed foods, known as tertiary processed foods. They require little preparation prior to eating and are typically packaged in single-serving portions. Convenience foods may include hot ready-to-eat dishes, shelf-stable products intended to be eaten at room temperature, or refrigerated or frozen products that require only heating before consumption. Candy, packaged baked goods, processed meats and cheeses, pasta dishes, TV dinners, frozen pizzas, single-serving portions of applesauce, pudding, fruit juices, soups, flavored milk, and some types of fast food are all examples of convenience foods.


Foods are processed for many different reasons:

Food safety is an important consideration for both whole and processed foods. It is of worldwide concern due to the increased globalization of food production and processing as well as the rise in international travel and tourism. People in the food industry use the acronym FAT TOM to remember the six conditions required for the growth of foodborne disease organisms: Food, Acidity, Time, Temperature, Oxygen, and Moisture. Monitoring these conditions is essential to food safety.

The move toward international standards in safety during food processing began in the 1960s when the National Aeronautics and Space Administration (NASA) asked the Pillsbury Company to invent and manufacture processed foods for space flights. To ensure the safety of the specialized foods required, the company instituted a preventive approach known as Hazard Analysis and Critical Control Points (HACCP). The U.S. Department of Agriculture (USDA) and the Food and Drug Administration (FDA) have made HACCP programs mandatory for meat, seafood, and juice processors, as well as retail or food service companies, while they are voluntary for other food industries.

In an HACCP program, food processors look for food safety hazards, defined as any biological, chemical, or physical property that would make a food unfit for human consumption. They then identify critical control points, which are points during the processing at which a food safety hazard can be prevented, eliminated, or reduced to an acceptable level. Other steps in an HACCP program include establishing critical limits for each control point; setting up a monitoring system; establishing corrective actions to be taken when critical limits are not met; setting up recordkeeping procedures; and verifying from time to time that the HACCP system is working as intended. The HACCP system is now used by a number of developed countries worldwide and has been extended to the manufacture of pharmaceuticals and cosmetics as well as processed foods.


The origins of food processing go back to human prehistory, as early humans are known to have cooked meat and dried it to preserve it. With the development of agriculture, various methods of crushing or milling whole grains to remove the husks and produce flour were created. Such cooking methods as boiling, baking, steaming, poaching, frying, and grilling, as well as fermentation and pickling, were known to the ancient Egyptians, Chinese, Greeks, Romans, and Native Americans. Prior to the invention of modern canning methods, salting and smoking were the major methods of food preservation for ancient and medieval soldiers and sailors.

Modern canning developed in response to military demands. It grew out of the work of Nicolas Appert (1749–1841), a French confectioner who won a prize offered by Napoleon in 1800 for anyone who could devise a safe and effective method of preserving food for an army on the march. Appert won the prize in 1810 after some years of experimentation. Appert's method involved placing foods in wide-mouthed glass jars, leaving some air space at the top, sealing the jars firmly with a cork, and dunking the jars in boiling water and boiling them for as much time as Appert thought appropriate for cooking the contents thoroughly. Appert's invention was followed the next year by Peter Durand, a British merchant who used tinned cans instead of glass jars to preserve food. Durand was granted a patent by King George III.

The pasteurization of milk was discovered by microbiologist Louis Pasteur (1822–1895) in 1862. In the twentieth century, food processing grew as an industry, and new techniques developed in response to the needs of troops in World Wars I and II, the space race, and the rising standards of living in the developed countries after 1945. Such advances as freeze drying, juice concentrates, and the use of artificial flavors and preservatives were all twentieth-century inventions, as was the introduction of TV dinners, convenience foods, and fast foods.

Methods of food processing

There are a number of different methods of food processing:

In addition to the various methods of food preparation, food processing also includes the packaging of foods as well as the application of edible coatings to fresh fruits and vegetables.

Recommended intakes

Currently, there is no recommended intake of whole foods versus processed foods. An increasing proportion of the world's foods are processed rather than being served as whole foods. A study published in 2009 reported that highly processed foods made up 50%–90% of the nutrients consumed in Europe, depending on the specific country. Another study of Inuit living near the Arctic Circle reported in 2009 that whole foods accounted for less than 40% of tribal members' diets, with the proportion of store-bought processed foods steadily increasing.

Reasons given for the growing worldwide shift toward processed foods include the general perceived safety of processed foods, the speed of modern methods of food transportation, and greater awareness of and desire for the variety of foods available around the world. This awareness in turn is the result of such communications media as television and the Internet, increased tourism, and increased population mobility.

The USDA's Dietary Guidelines for Americans 2010 states that people should lower the number of calories they take in from solid fats and added sugars, as well as foods containing refined grains, and especially any refined-grain products containing solid fats, added sugars, and excess sodium (salt). Most Americans two years and older eat a diet high in sodium, consuming approximately 3,400 mg each, in comparison to the 2,400 mg recommendation. Most of the sodium in American diets comes from processed foods where salt has been added. The USDA recommends eating more fresh foods and fewer processed foods to help limit sodium intake. The guidelines advise that half of a person's daily intake of grains should be whole grains—for a person consuming a 2,000 calorie diet, this would be no more than three one-ounce equivalents of processed grains per day (one ounce being about 1/3 cup of pasta or one slice of bread).

Solid fats and added sugars, mostly from processed foods, contribute to nearly 800 calories, or 35% of total calories per day for the average person in the United States. The USDA guidelines allow for about 5%–15% of total calories to come from added fats and sugars, or 32 grams in a 2,000 calorie diet. The majority of sugars consumed in “typical” Western diets are sugars added to foods during processing, accounting for 16% of a person's total caloric intake. These added sugars are used in processed foods to sweeten the flavor of foods and beverages and improve their palatability (taste). They also assist in preservation purposes and to provide viscosity, texture, body, and browning capacity to foods that have been processed. In general, the main intake of sugar in the United States is not from whole foods such as fresh fruit but instead comes from highly processed foods such as soda, energy drinks, and sports drinks (36% of added sugar intake); grain-based desserts (13%); sugar-sweetened fruit drinks (10%); dairy-based desserts (6%); and candy (6%).

According to the USDA, 19% of the total calories in American diets comes from solid (saturated) fats, which contribute few essential nutrients and no dietary fiber. The top food sources of solid fats in the United States are foods that are processed and include grain-based desserts (11% of all solid fat intake); pizza (9%); regular (full-fat) cheese (8%); sausage, franks, bacon, and ribs (7%); and fried white potatoes (5%). The guidelines state that no more than 10% of total daily calories should come from saturated fats but emphasize trying to consume less than 7%.


Consumers deciding on food purchases need to take a number of factors into consideration when choosing between whole or processed foods:

The hard outer layer of a whole grain.
Convenience foods—
Foods that require little or no preparation before eating. They are also known as tertiary processed foods.
Empty calories—
Calories in processed foods that have the same energy content as other calories but lack nutritional value. Most empty calories come from processed carbohydrates or fats.
The starchy tissue that surrounds the germ of a whole grain and supplies it with nourishment. It is the part of the grain that remains after the whole grain has been refined.
Functional foods—
Foods that claim to have a health-promoting or disease-preventing property beyond the basic function of supplying nutrients. They may be either fresh or processed, although most are processed or fortified with vitamins or other additives.
The seed embryo in a whole grain; the reproductive portion that will grow into a whole plant.
Junk food—
An informal term to describe foods with little or no nutritional value or that contain ingredients considered unhealthy for consumption on a regular basis.
Also spelled kimchee or kim chee, a traditional Korean dish made of fermented cabbage and other vegetables.
In the context of food production, foods that have been grown, transported, or processed without the use of pesticides, antibiotics, fertilizer, or other chemicals.
A process for extending the shelf life of milk or other beverages by heating them to a temperature that destroys some (though not all) of the bacteria present. The two methods of pasteurization most commonly used involve either heating for 15–20 seconds to 161°F (72°C) or heating to 280°F (138°C) for a fraction of a second.
Raw milk—
Milk that has not been homogenized or pasteurized.
Whole grains—
Cereal grains that contain the germ, bran, and endosperm of the grain. They can usually be sprouted, whereas refined grains cannot.


There are many documented risks of eating a diet that is based on processed foods over whole foods. Research has linked an increased risk of cardiovascular disease, diabetes, and cancer with a high consumption of processed meats, especially meat processed with nitrates/nitrites. High sugar intake increases risk for dental caries, and consuming large amounts of saturated fats has a strong link to increasing both total cholesterol and low-density lipoprotein (LDL, or “bad”) cholesterol, which both increase the risk of developing cardiovascular disease. People with hypertension, diabetes, or chronic kidney disease must eat a diet low in sodium, which is difficult to achieve if eating processed foods. Much evidence has documented a link between decreased sodium intake and lowered blood pressure. The Dietary Approaches to Stop Hypertension (DASH diet) is an eating plan that is based mostly on whole foods to help reduce high blood pressure. Having elevated blood pressure above the normal range increases an individual's risk of cardiovascular disease, congestive heart failure, and kidney disease.

Risks from whole foods

Risks from whole foods include:

Risks from processed foods

The risks of consuming processed foods include:

Parental concerns

Parents may need to consult with a doctor or registered dietitian to make sure that children or other dependent people in their care are eating a variety of healthful foods, whether whole or processed; that the foods are properly stored and prepared; that the person is not purchasing or consuming foods excluded by a special diet; and that junk foods are kept to a minimum.

See also



Nestle, Marion. What to Eat. New York: North Point Press, 2007.

Novak, John S., Gerald M. Sapers, and Vijay K. Juneja, eds. Microbial Safety of Minimally Processed Foods. Boca Raton, FL: CRC Press, 2003.

Shahidi, Fereidoon, et al. Quality of Fresh and Processed Foods. Advances in Experimental Medicine and Biology. New York: Springer Science + Business Media, 2004.


Barr, Sadie B., and Jonathan C. Wright. “Postprandial Energy Expenditure in Whole-Food and Processed-Food Meals: Implications for Daily Energy Expenditure.” Food and Nutrition Research 54 (July 2, 2010). http://dx.doi.org/10.3402/fnr.v54i0.5144 (accessed April 23, 2018).

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Lucock, M., and Z. Yates. “Folic Acid Fortification: A Double-Edged Sword.” Current Opinion in Clinical Nutrition and Metabolic Care 12, no. 6 (November 2009): 555–64.

Mataragas, M., P. N. Skandamis, and E. H. Drosinos. et al. “Risk Profiles of Pork and Poultry Meat and Risk Ratings of Various Pathogen/Product Combinations.” International Journal of Food Microbiology 126, no. 1–2 (August 15, 2008): 1–12.

Oliver, S. P., et al. “Food Safety Hazards Associated with Consumption of Raw Milk.” Foodborne Pathogens and Disease 6, no. 7 (September 2009): 793–806.

Sánchez-Moreno, C., et al. “Nutritional Approaches and Health-Related Properties of Plant Foods Processed by High Pressure and Pulsed Electric Fields.” Critical Reviews in Food Science and Nutrition 49, no. 6 (June 2009): 552–76.

Santarelli, R. L., F. Pierre, and D. E. Corpet. “Processed Meat and Colorectal Cancer: A Review of Epidemiologic and Experimental Evidence.” Nutrition and Cancer 60, no. 2 (2008): 131–44.

Sathe, S. K., and G. M. Sharma. “Effects of Food Processing on Food Allergens.” Molecular Nutrition and Food Research 53, no. 8 (August 2009): 970–78.

Shewry, P. R. “Wheat.” Journal of Experimental Botany 60, no. 6 (April 2009): 1537–53.

Slimani, N., et al. “Contribution of Highly Industrially Processed Foods to the Nutrient Intakes and Patterns of Middle-Aged Populations in the European Prospective Investigation into Cancer and Nutrition Study.” European Journal of Clinical Nutrition 63, no. S4 (November 2009): S206–S225.

Todd, E. C., et al. “Outbreaks Where Food Workers Have Been Implicated in the Spread of Foodborne Disease. Part 6. Transmission and Survival of Pathogens in the Food Processing and Preparation Environment.” Journal of Food Protection 72, no. 1 (January 2009): 202–19.

Vargas, M., et al. “Recent Advances in Edible Coatings for Fresh and Minimally Processed Fruits.” Critical Reviews in Food Science and Nutrition 48, no. 6 (June 2008): 496–511.


Centers for Disease Control and Prevention (CDC). “Food Safety.” http://www.cdc.gov/foodsafety/index.html (accessed April 23, 2018).

U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th ed. December 2015. http://health.gov/dietaryguidelines/2015/guidelines/ (accessed May 1, 2018).

U.S. Food and Drug Administration (FDA). “The Dangers of Raw Milk: Unpasteurized Milk Can Pose a Serious Health Risk.” https://www.fda.gov/food/foodborneill-nesscontaminants/buystoreservesafefood/ucm079516.htm (accessed April 23, 2018).


Academy of Nutrition and Dietetics, 120 South Riverside Plz., Ste. 2000, Chicago, IL, 60606-6995, (312) 899-0040, (800) 877-1600, amacmunn@eatright.org, http://www.eatright.org .

British Nutrition Foundation, High Holborn House, 52-54 High Holborn, London, UK, WC1V 6RQ, +44 20 7404 6504, Fax: +44 20 7404 6747, postbox@nutrition.org.uk, http://www.nutrition.org.uk .

Center for Food Safety and Applied Nutrition (CFSAN), U.S. Food and Drug Administration, 5100 Paint Branch Pkwy., College Park, MD, 20740, (888) SAFEFOOD (723-3366), consumer@fda.gov, http://www.fda.gov/Food/default.htm .

Centers for Disease Control and Prevention, 1600 Clifton Rd. NE, Atlanta, GA, 30333, (800) CDC-INFO (232-4636), TTY: (888) 232-6348, cdcinfo@cdc.gov, http://www.cdc.gov .

Food Safety and Inspection Service (FSIS), U.S. Department of Agriculture (USDA), 1400 Independence Ave. SW, Washington, DC, 20250-3700, (888) 674-6854 (USDA Meat and Poultry Consumer Hotline), MPHotline.fsis@usda.gov, http://www.fsis.usda.gov .

U.S. Food and Drug Administration, 10903 New Hampshire Ave., Silver Spring, MD, 20993-0002, (888) INFO-FDA (463-6332), http://www.fda.gov .

Rebecca J. Frey, PhD
Revised by Megan Porter, RD

  This information is not a tool for self-diagnosis or a substitute for professional care.