Processed food
Processed food was invented to make food more profitable by extending its shelf life. I do not think it was intentional, but it so happen, that additives used to prolong the shelf life in many cases resulted in food being more addictive, rich in calories from bad carbs and bad fats.
Simple definition: if it does not look like natural food, it is likely processed. It is always packaged in some plastic or box. Processed food other than meat often does not require refrigeration. Some examples include chips, cereals, nutrition bars, energy drinks, sausages, and burgers.
There are a lot of healthy processed food. Lately we started to have a wide selection of healthy low calorie high fiber nutrition bars. Unfortunately, it is still often an art to find a healthy food amongst processed. I hope at one point we will be sophisticated enough to have only healthy selections amongst processed food. For the moment it appears that many of the processed food is unhealthy and strongly linked to the epidemic of obesity.
A rule of thumb: if not sure - exclude.
What is so bad about processed food? Eating such foods can stimulate appetite, promote weight gain, and increase bad cholesterol.
Most processed food has added sugars under different names other than simple “sugar" (see previous section)
Most of the time, the label is so complicated that it it takes a chemist to understand it. Most grains and legumes included in processed food are usually refined, making them essentially simple unhealthy sugars. Trans fats are often added to enhance preservation (even bacteria do not want to consume it).
Cooking food and vegetables. It is a lighter, less aggressive but still one of the forms of food processing. Food Sauces. What is the purpose? To make food taste better and easier to digest. Cooking food gives us the ability to better digest and utilise all of the present nutrients. Sauces make food taste better and, in many cases make it more addictive. Besides of spices many sauces have significant amounts of sugars and salts added. What is the primary goal of a weight loss diet? We want to be able to eat more, to have reduced appetite, and, of course, lose weight. Cooking and adding sauces accomplishes exactly opposite.
I think that food ideal for weight loss should be minimally processed, contains minimal sauces or fats, and to be as close as possible to its natural state as possible.
P.S.
Just for exercise look at the label of any packaged food. Most of the time at least one of the components on the label would be one or another sugar, unless you are looking at the bottled water. This is not a conspiracy theory, this is a reality of 21st century, we and our appetite are being poisoned.