1. They are high in sugar and/or high fructose corn syrup, which programs your body to consume more calories and store fat.
2. You tend to overeat when you eat processed foods. Junk foods “override” your body’s natural intrinsic regulator, and as a result, can stimulate a strong rewards response in your brain that causes you to overeat.    
3. They are loaded with artificial ingredients. The artificial colors, flavors, preservatives, and texturants in these unhealthy foods are touted to be “safe,” but can actually lead to many health problems, according to numerous studies
4. Processed foods are typically high in refined carbohydrates that break down to sugar in your body, and are low in nutrients including fiber. 
5. Processed foods are often high in trans fats and processed vegetable oils. These are known to promote inflammation, which is a hallmark of most chronic and/or serious diseases.
6. You digest processed foods with less energy and time. Not only can you eat processed foods faster (think of the difference between chewing a piece of broccoli and munching on a potato chip), but your body also digests them quicker.
7. These unhealthy foods are ADDICTING. Processed foods stimulate dopamine, a neurotransmitter that makes you feel good even though the food lacks fiber and nutrients. This can lead to excessive food cravings and, ultimately, food addiction.

These reasons should be more than enough to convince you to stop gorging on unhealthy junk foods – instead, I recommend swapping them for real whole foods that can do wonders for your health.

Cancer-Causing Acrylamide Is Another Major Processed Food Risk

If you’re looking for motivation to stop eating processed foods, remember that this is about more than eating empty calories or even too much sugar. Processed foods contain many substances that are contrary to health, and acrylamide is one of them. Acrylamide can form in many foods cooked or processed at temperatures above 212°F (100°C), but carbohydrate-rich foods are the most vulnerable to this heat-induced byproduct. As a general rule, the chemical is formed when food is heated enough to produce a fairly dry and “browned” surface. Hence, it can be found in high amounts in many processed foods, especially:

Potatoes: chips, French fries, and other roasted or fried potato foods

Grains: bread crust, toast, crisp bread, roasted breakfast cereals, and various processed snacks

Animal studies have shown that exposure to acrylamide increases the risk of several types of cancer, and the International Agency for Research on Cancer considers acrylamide a “probable human carcinogen.” Potato chips in particular are notoriously high in this dangerous chemical. So high, in fact, that in 2005 the state of California actually sued potato chip makers for failing to warn California consumers about the health risks of acrylamide in their products. A settlement was reached in 20087 when Frito-Lay and several other potato chip makers agreed to reduce the acrylamide levels in their chips to 275 parts per billion (ppb) by 2011, which is low enough to avoid needing a cancer warning label.