Most of the health problems that arise from fast-food consumption are a result of high levels of saturated fat, trans fat, sugar and sodium. Fast-food restaurants often use portions of these ingredients that exceed recommended levels, in an attempt to add flavor to their food and make it more desirable. Many major health conditions are associated with fast-food consumption, including heart disease, stroke, diabetes and hypertension.
Fat for Cardiovascular Disease
Many foods use trans fats to bring costs down, preserve foods and add desirable flavors and textures. Fast-food restaurants often deep-fry foods using trans fats. These unhealthy, man-made fats can both lower your good cholesterol while increasing bad cholesterol. This, in turn, raises the risk of developing heart disease, stroke and type-2 diabetes. A 2010 study published in the "Journal of the American Dietetic Association" notes that when 2 percent of total caloric intake is composed of trans fat, the risk for cardiovascular disease rises by a whopping 23 percent. The American Heart Association notes that saturated fats, when consumed in excess, also increase the risk for heart disease and stroke.
Sugar for Diabetes
Fast foods are typically served with soft drinks, milk shakes and other beverages that contain high levels of sugar. These added sugars contain no nutritional value and can promote weight gain, thereby negatively affecting heart health. A 2013 study published in "Current Opinion in Clinical Nutrition and Metabolic Care" notes that high-sugar diets increase insulin resistance, promote weight gain and are a major risk factor for Alzheimer's disease and type-2 diabetes. The study concluded that reducing added-sugar consumption could increase longevity and quality of life.
Sodium for Hypertension
Sodium's flavor-enhancing properties make it a favorite ingredient among fast-food restaurants. The U.S. Food and Drug Administration notes that over 75 percent of dietary sodium comes from restaurant foods and packaged foods. When high levels of sodium are consumed, blood pressure rises, and the risk for hypertension and heart disease increases. A 2012 study published in the "American Journal of Medicine" notes that a high sodium intake is not only linked to hypertension but stroke, ventricular hypertrophy (the thickening of the heart's walls) and proteinuria -- a condition that indicates kidney damage.
The American Heart Association recommends no more than 2 grams of trans fat per day and no more than 16 grams of saturated fat per day. The U.S. government's dietary guidelines recommend a limit of 2,300 milligrams of sodium per day -- an amount equal to 1 teaspoon of salt. The American Heart Association recommends no more than 25 grams of added sugar per day for women and no more than 38 grams for men. By only eating fast food on special occasions and choosing healthier options -- such as salads, sugar-free beverages and foods that are not fried -- you can avoid the dangerous health consequences of fast food.