Processed foods are foods that have been altered from their natural state, either for added taste, texture, convenience, safety reasons, or to extend their shelf life. Often these foods have had preparation steps incorporated into their processing, or in cases of frozen meals have been completely prepared during processing. 
The methods used for processing foods include: dehydrating, freezing, refrigeration, canning and aseptic processing. Quite simply, if the food is boxed, bagged, canned or jarred and has a list of ingredients on the label, it's processed.
Added Processed Food Ingredients
The primary benefit of processed food is convenience. However, convenience isn’t the only thing that one gets when they consume these types of foods.
Following is a list of frequently used food additives in processed foods: 
- Bleach This chemical is often used to disinfect and deodorize e.g. packaged chicken
- Emulsifiers, thickeners and stabilizers are designed to add viscosity to liquids and bind or stabilize other ingredients and commonly found in dressings, sauces and desserts.
- Many have natural sources, such as guar gum (from the guar bean), xanthium gum (from glucose), carrageen (from seaweed) and pectin (from fruit). Mono and di-glycerides of fatty acids are sometimes derived from genetically modified soybeans.
- Disodium inosate, disodium 5-ribonucleotide, or disodium guanylate, are food flavourings used to make foods taste more savoury.
- Maltodextrin is a sweet polysaccharide made from corn and is as rapidly absorbed as glucose. It is used primarily to give body, flavour, texture and viscosity to foods like packaged desserts and potato chips.
- Phosphates are antioxidants and acidity regulators (raising agents).
- Potassium nitrate (saltpeter) is a food preservative that is also used in fertilizers and fireworks.
- Potassium sorbate is an antifungal which helps to increase shelf life.
- Sodium acetate is a chemical used in the paper industry and in heating pads however, in food processing it is used as a preservative.
- Sodium nitrite is a colour-fixative and preservative that is only currently used in EU countries in minute quantities, as it is toxic to mammals. This substance is banned in the EU in foods for children under three years of age.
- Taurine, glucuronolactone and caffeine are stimulants that are present in some carbonated and energy drinks.
Potential Benefits of Processed Foods
Following are the potential benefits of processed food products: 
- Processing has allowed for increased seasonal availability of many foods
- Ability to transport delicate perishable foods across long distances
- Deactivation of pathogenic micro-organisms and reduction of food-borne diseases (e.g. salmonella)
- Less susceptibility to early spoilage
- Increased variety in food choices
- Enhancement of food flavour and texture
Potential Health Risks of Processed Foods
Following are the health risks associated with the consumption of processed foods:
- The use of equipment in the mechanical process of mixing, grinding, chopping and emulsifying introduces a number of contaminate risks 
- The preservatives, chemicals, colourings and additives in processed foods can increase the toxic burden on the liver
- Consumption of processed foods can engender silent inflammation, which underlies many chronic degenerative diseases like diabetes, cancer, osteoarthritis, and cardiovascular disease. 
- Many processed foods are high in sugar and require more immediate insulin release for their digestion.
- Chronic excess insulin release due to high sugar consumption can lead to diabetes and metabolic syndrome
- Ultra-processed foods often contain hydrogenated (trans) fats which increase the shelf-life but cause cellular damage due to oxidative stress 
- Trans fats decrease HDL cholesterol and increase LDL cholesterol, triglycerides and levels of artery-clogging lipoproteins which increases the risk of heart disease
- Ultra-processed foods lack the minerals, vitamins, healthy fats, phytochemicals, and insoluble fiber found in whole foods which nourish our bodies and protect against disease
- Long-term dietary consumption of processed foods can be a prescription for weight gain and obesity
- Processed foods have been chemically manipulated to taste good without bringing on a feeling of satiety which can lead to over-eating
- Processed foods such as cookies, potato chips and white bread, are more calorically dense than whole foods because they have had water removed to help decrease transportation costs and extend their shelf life
- Increased risk of depression has been linked to the consumption of processed foods
- A 2009 study found that diet high in processed food had a 58% higher risk of depression than those who ate very few processed foods. 
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