10 Secrets of Fast Food Chains They Don't Want to Talk About

Fast-food chains are trying to sell us more food for less money. We think that this is good and profitable, but this is not entirely true.

Here are some of the secrets the fast-food industry doesn't want you to know.

10 PHOTOS

1. Fast food is meant to be eaten quickly.

It takes 20 minutes for the "I'm full" signal to travel from your belly to your brain. Thus, the faster you eat, the more food you will eat until you are full.

2. Fast food does not need to be chewed for a long time.

Another trick to make you eat more is that obese people chew their food 11.9 times before swallowing it, while thin people chew it 14.8 times, according to one study. Fast food tends to be chewed very quickly.

3. Today's food contains more calories than the food of the 1980s.

In fact, we now consume twice as many calories in cafes and restaurants as we did 30 years ago. See how much our food has changed:
Pizza: 70 percent more calories.
Cheeseburger: 75 percent more calories.
French fries: 190 percent more calories.

4. Your soda might be dirtier than the toilet.

Ice and soda machines are notoriously difficult to clean, making them real Petri dishes.

5. Your meat is chemically cleaned.

The chemicals we usually associate with cleaning are being purposefully injected into fast food meats. What for? Compounds such as ammonium hydroxide can kill E. coli and other organisms. They also reduce the acidity of meat and other foods, making it difficult for pathogens to survive. Is this practice safe? The USDA says yes. Does the idea of eating a chemically washed hamburger sound good? Not really.

6. The grill is fake.

Grill strips on fast food burgers and chicken serve to make us think the meat was cooked on a real grill. These markings were most likely already applied at the factory with dyes. Smoke and charcoal flavorings are added to complete the illusion.

7. Some fast food looks too good for its age.

In 2010, New York-based photographer Sally Davis put a McDonald's hamburger and French fries in a jar. Five months later, the food still looked edible, with no hint of mold.

8. There are more ingredients in a salad than you think.

Many fast-food chains offer salads these days. But not everything opens up to your eyes at the sight of a salad. How about propylene glycol? Many fast-food chains clean their salads with this chemical to keep the greens crispy.

9. Your coffee can ruin your mood.

Styrofoam cups can release styrene, a neurotoxin that can cause depression and loss of concentration.

10. McDonald's oatmeal is not the healthiest food on their menu.

A cereal with 32 grams of sugar is more than a bag of M&Ms. There is nothing healthy to start your day with high sugar levels.