calorie diet menu

Can You Find Some Language Mistakes In The Following Text?

I’m not a native speaker, so I need help. This is very important assignmetn, and i shouldn,t have any mistake!!! Help please!!!!!!!!!
The text:
There are three important steps to follow in order to have a healthy organism: have a good dietary regiment, do physical activities, and allow enough time to rest.
The first and most popular step that assure a good health is choosing an appropriate diet. Dieticians reveal that the core guideline in our diet is choosing the proper food. Some people rely on calorie constraint. But this won’t refine their health conditions. Contrary to what people may think, low-calorie diet isn’t so beneficial, because it slows the metabolism. Moreover, insufficient food intake can cause weakness and collapse. You just have to be careful of what and when you eat. Many people in the Orient are used to eat late at night. However, this is not a good practice. Another important rule in our diet is to divide our daily amount of food into smaller and frequent portions. Integral bread is preferable. Finally, many people believe that supplements can improve their health. However, they don’t have to forget that nutrition supplements can’t substitute food.
In the modern world few people have time to walk in the mountain and most people don’t work in physical jobs. Thus, they need some kind of artificial physical activity like fitness. The government should make more investments into sport and subsidy sport clubs for young people. People who play some sport are usually healthier and have stronger immune system and this is not a coincidence. The statistics denote that sport can restrain the risk of heart diseases and diabetes. They are two opposite kind of people. Some people feel reluctance to engage in sports, but they don’t have any notion of the importance of sport for health. There are also other people that exaggerate in their dedication to sport and overpass the healthy limits. This is the case of young teenagers trying to bulk up muscle mass with steroids. Their external beauty, however, covers many health problems.
The last step is to allow enough time to rest. Some people are subordinated to their jobs and they work late at night, many students also stay after midnight to prepare for a forthcoming exam, for example. If they don’t finish their job, they can’t sleep. This is their philosophy of life. However, our minds have finite capacity. Sleep should be always priority.
To summarize, a good health requires a compilation of a good diet, a lot of sport, and enough time for rest. If only one of these things is missing, you’ll hardly survive!