To start with, the word diet has two different meanings:
- In the first is when one person eats a small or limited quantity of food in order to become thinner. This can be combined with miracle products whose goal is to help in the process of reducing your weight.
- The second one is the food that a person usually eats. From this point of view everybody follows a diet and the eaten food depends on your living style and your culture. That's why nutritionists usually talk about mediterranean diet, fast food and so on.
Fortunately I've never been on a diet to become thinner. I consider this type of diet dangerous for health and nobody should follow a diet without the advice of a specialised doctor.
Medical institutions consider that a healthy diet should include all type of food. Also, It has to be based in fruits, vegetables and legumes. On the contrary it has to cut down salt and sugar. Besides it has to limit the calories intake from saturate fat.
On the other hand, the diet should be combined with Physical activity and resting 8 or 9 hours a day.
As to the consequences, they are usually good if people follow the advices of a doctor when being on a diet. People reduce their weight and keep their health.
However there are lots of problems when people follow a diet they have seen on tv, or in a magazine. The problems can be physical: heart attack, malfunction of different organs of your body like the kidney, you can lose the vision and so on. And they can be emotional because you can suffer depression.
Besides, they can be worsened by the use of miracle products because they are not controlled by authorities and thereby the can include any toxic substance in their composition.
In conclusion if you put on a diet, you should follow the advices of a doctor and adopt healthy lifestyle.