Junk foods, which are high in "empty calories," provide a lot of calories while supplying very few nutrients. These additional calories can lead to weight gain, which can increase the risk for serious chronic diseases.
Junk food often contains additional calories in the form of solid fat or sugar. Solid fat is found in ingredients such as butter, beef fat and shortening, which are often added to processed foods. Added sugar refers to sugars and syrups that are added to processed foods. Because solid fat and sugar are calorie dense, junk food contains a lot of calories while providing few healthy nutrients. These extra calories can lead to obesity, which increases a person's risk for several serious chronic diseases, such as coronary heart disease, cancer, stroke, liver and gallbladder disease and respiratory problems.
When a person consumes junk food instead of healthy choices, he might not consume enough vitamins and minerals. This can lead to nutrient deficiencies, which can have even more negative effects on the body. One of these negative effects is a decrease in immune function.
Some people are also concerned with the potential consequences that the additives in junk food may have on the body. Examples of additives in junk food are dyes, high fructose corn syrup and aspartame.