Nowadays it has not been easy to have a healthy and adequate diet that meets nutritional needs due to the change in eating habits, characterized by the excess consumption of foods that are very energetic and rich in saturated fat. This change is closely associated with obesity, hypertension and cardiovascular disease.
One of the biggest problems we notice is in the school environment. How can a student choose healthier foods in a canteen, or how to prepare a snack that is practical or even healthy at the same time?
Below, we will give some tips on choosing healthy snacks that students can make to promote health. A healthy snack needs to have colorful, beautiful, pleasant and nutritious foods made with hygiene, in addition to presenting balanced amounts of: proteins, fats, carbohydrates, vitamins, minerals and fiber. Taking all these aspects into consideration, a mother and child can choose, for example, a natural sandwich, preferably with wholemeal bread and topped with tomatoes, lettuce and carrots, and natural yogurt and fruit as a drink. Today, there are thermal lunch boxes that make it possible to carry more perishable foods safely.
If the child prefers to eat snacks from the school canteen, parents need to advise on how to make the healthiest choice when purchasing, giving preference to foods such as natural snacks (avoid those containing mayonnaise), baked snacks, natural juices and avoid processed foods, fried foods, soft drinks, stuffed cookies and chocolates. These foods are high in calories and contain a lot of salt. For example, see the comparison between natural orange juice and a regular soda.
Studies have shown that the foods most consumed by teenagers in high school canteens are sweets, snacks and soft drinks instead of juices and milk and their derivatives. Given that teenagers need calcium to prevent osteoporosis in their adult face, it is advisable to choose snacks such as yogurt and low-fat cheeses. In the canteen you can prefer roasts, simple cake without filling and fruit salad.
For young university students, a snack option is to take dried fruits such as: apricots, grapes, which do not spoil quickly and cereal bars (preferably without chocolate). Fresh fruits like apples are convenient to take and help with satiety. Nuts and chestnuts have a considerable amount of protein and lipid, thus constituting good sources of energy. Furthermore, they are also known for their antioxidant power and improved memory and mood. 
Sources:
FREITAS, Jullyana Borges; NAVES, Maria Margareth Veloso. Composition and chemistry of edible nuts and seeds and their relationship to nutrition.
MARINA MARQUART FELICE ET AL. Analysis of School Snacks Consumed by Adolescents, 2007 Secretary of Agriculture and Supply of the State of São Paulo. Play and learn, 2011.