Lesson 2 Understanding the components of food

Why these nutrients are important for the human body?

Nutrients are important for proper health and development.

  • They provide energy
  • They’re Needed for Body Structures
  • They Regulate Body Functions

There are 6 Major Categories of Nutrients

  1. Carbohydrates
  2. Fats
  3. Minerals
  4. Proteins
  5. Vitamins
  6. Water

Bodies are made of bones, blood, muscle, fat, and water. Water is a nutrient that makes up 60% of our body weight. It is important in many functions; it is part of every cell in every tissue in the body. Water carries other nutrients to all parts of the body; it carries waste out of the body, and it helps to regulate body temperature.

Protein is a nutrient used to make and repair our body cells (like blood and muscle cells). About 1/2 of your dry body weight is protein. If you do not eat enough carbohydrates, protein will be changed to carbohydrates so that you can get energy. If you eat too much protein, the extra amount will be changed into fat and stored in your muscles to use later. Your body cannot store protein as protein, so you need to eat some every day. Your muscles need some protein every day especially if you play sports, run or exercise.

Carbohydrates are the primary (number one) source of energy for our bodies. With enough carbohydrates, the protein and fat that we eat can do their jobs. If you remember our study of the food guide pyramid, you’ll remember that the carbohydrates were the largest group on the bottom of the pyramid. There are 2 types of carbohydrates, SIMPLE and COMPLEX. COMPLEX carbohydrates we were talking about have another benefit. They are high in fiber. Fiber is the plant material that cannot be digested by your body but is important for the good functioning of the digestive system.

Fat is a nutrient that is the most concentrated source of energy for the body. One of the reasons is so it can be used for energy later. The fat we store in our body protects our vital organs. Fat gets deposited under the skin where it works to keep our bodies warm by insulating and preventing heat loss.

Vitamins are a category of nutrients that include: Fat-soluble vitamins A,D,E,and K Water-soluble vitamins B and C. Vitamins keep us healthy, prevent disease, help us grow properly, use energy, have good vision and keep us in proper condition. As with calories, children need more vitamins every day because they are growing, and their bodies are developing.

Minerals are another nutrient category that, like vitamins, include a number of different forms. When we talk about minerals, we are referring to calcium, iodide, phosphorous, fluorine, potassium, zinc and iron. Minerals help you have strong bones and teeth and healthy blood. They also help your body stay regulated in many ways. Calcium and iron are two of the important minerals

Food Chemistry | The Science of Food Components

This will shortly explain what food is made of and how nutrients are used by the body. It is important to have a balanced nutrition to ensure you give your cells energy. Energy can be generated by different types of food, but it is important to receive energy from nutritious food to gain all the benefits and do less damage.

How a diet high in refined and added sugars it can be bad for you?

  • Consuming free sugars increases the risk of dental caries (tooth decay). Excess calories from foods and drinks high in refined and added sugars also contribute to unhealthy weight gain, which can lead to excess weight, obesity and diabetes.
  • Recent evidence also shows that free sugars influence blood pressure and serum lipids, and suggests that a reduction in refined and added sugars intake reduces the risk for cardiovascular diseases.

How excess consumption of salt can be bad for you?

  • High sodium intake and insufficient potassium intake contribute to high blood pressure, which in turn increases the risk of heart disease and stroke.

How excess consumption of saturated fats can be bad for you?

  • Eating foods high in saturated fats (e.g., fried foods, red meat, processed meat) increases the risk of cardiovascular disease, stroke and cancer.

The Healthy Eating Pyramid is a simple visual guide to the types and proportion of foods that we should eat every day for good health. It contains the five core food groups, plus healthy fats, according to how much they contribute to a balanced diet.

The bottom-two layers include the three plant-based food groups:

  • Vegetables and legumes
  • Fruits
  • Grains (Choose mostly wholegrains over highly processed, refined varieties)

These layers make up the largest portion of the Pyramid because plant foods should make up the largest portion of our diet – around 70% of what we eat!


  • Older children, teens and adults should aim to have at least 2 serves of fruit and 5 serves of vegetables or legumes each day.
  • The top layers of the pyramid (healthy fats, milk, yoghurt, cheese & alternatives, meat, poultry, fish, eggs) should be consumed but in smaller proportions (30%) than the above. 

The health eating plate visual guide can help you understand portions without worrying about grams or if you don’t have a scale. Use the Healthy Eating Plate as a guide for creating healthy, balanced meals.

You can find the healthy eating plate in various languages here: https://www.hsph.harvard.edu/nutritionsource/ healthy-eating-plate/translations/