Fast food breaks down quickly, causing a rapid rise in blood sugar due to refined carbohydrates and added sugar. In turn, this causes an abnormally large increase in insulin, resulting in a drop in blood sugar. This can make people feel tired. Insulin increases hunger a short time after a meal.
In the short term, fast food affects blood sugar and blood pressure, increases inflammation and may mean that a person is not getting the necessary nutrients. In the long term, a diet rich in fast food could lead to problems with digestion, immunity, inflammation, heart health, obesity, and more. When choosing between a healthier option and junk food, keep in mind that including just one healthy meal a day in the typical American diet could reduce the body's overall stress and inflammation. If you want to enjoy junk food from time to time but are concerned about the impact on your health, take a look at your general health habits.
Following a poor quality diet high in junk food is linked to an increased risk of obesity, depression, digestive problems, heart disease and stroke, type 2 diabetes, cancer and premature death. In addition, the rapid rise in blood sugar from eating junk food that is high in refined carbohydrates and added sugars can cause an increase in insulin and cause a rapid drop in blood sugar. The amount of inflammation and oxidative stress your body will experience after eating junk food from time to time seems to depend on the “big picture” of your choices over time. While there are a growing number of healthier fast food options, most fast food can still be classified as junk food.
A small study of 12 healthy young men found that eating junk food for just five days reduced the muscles' ability to convert glucose into energy, even though they didn't consume more calories as part of the study.
