NUTRITION is the science of how the body uses food — the food you eat affects your body and health (Stiver, 2.1 Nutrition Note, page 1).
One of the basic needs provided by foods is NUTRIENTS — chemicals from food that your body uses to perform functions, such as building and repairing tissues (Stiver, 2.1 Nutrition Note, page 1).
Macronutrients
MACRONUTRIENTS — carbohydrates, proteins, fats, and water — are needed by the body in large quantities (Stiver, 2.1 Nutrition Note, page 3).
Carbohydrates
The body gains most of its energy using carbohydrates (Stiver, 2.3 Carbohydrates Note, slide 7). This nutrient is essential for the brain to properly function (Stiver, 2.1 Macro-nutrients Handout, page 1). Excess carbohydrates are converted and stored in the body as fat. When there are insufficient carbohydrates to support the body, other energy-providing nutrients— such as fats and protein — are used instead. (Stiver, 2.3 Carbohydrates Note)
Proteins
Proteins are used by the body to grow and repair cells and tissues. These nutrients are considered the “building blocks” of the body and are formed by folded chains — POLYPEPTIDES — of chemical building blocks called AMINO ACIDS. Proteins help fight disease and provide energy when carbohydrates and fats are insufficient. (Stiver, 2.5 Proteins Note)
Fats
Fats are useful as a source of stored energy in the body and are more concentrated sources of energy, which means one gram of fat will release more energy than one gram of carbohydrate or protein (Stiver, 2.1 Nutrition Note, page 3). Fats are made up of essential FATTY ACIDS and carry fat-soluble vitamins (Stiver, 2.4 Fats). Furthermore, they provide cushioning and insulation for body organs — like the heart and liver — against extreme temperatures (Stiver, 2.1 Macro-nutrients Handout, page 2). However, it is important to consume fats in moderation as overconsumption can increase the chances of developing illnesses like heart disease and diabetes (Stiver, 2.4 Fats).
Water
Water is extremely important for all life! 50–70% of our body weight is water! It is a standard requirement to drink 8 cups of water every day (Stiver, 2.6 Water and Micronutrients). Water serves many purposes in the body:
- Delivers nutrients to cells around the body
- Regulates body temperature
- Lubricates joints and muscles
- Acts as a shock absorber in the eyes, spine, and joints
- Helps remove waste from the body
(Stiver, 2.1 Macro-nutrients Handout, page 2)
Micronutrients
MICRONUTRIENTS — vitamins and minerals — are required by the body in smaller quantities. These nutrients do not provide energy, however, they are important because they perform hundreds of roles in the body, including:
- Supporting bones
- Healing wounds
- Boosting the immune system
- Helping repair cells
(Stiver, 2.6 Water and Micronutrients)
Vitamins
There are 13 vitamins needed for good health (Stiver, 2.1 Macro-nutrients Handout, page 3). Some vitamins are can be found in water (vitamins C and B) or fat (vitamins A, D, E, and K) as they are water- and fat-soluble (Stiver, 2.6 Water and Micronutrients).
Minerals
MAJOR minerals are needed in relatively large amounts, whereas TRACE (MICRO) minerals are needed in relatively small amounts — however, major and trace minerals are equally important. ELECTROLYTES are minerals that help maintain fluid balance in the body. (Stiver, 2.6 Water and Micronutrients)
REMEMBER: It is important to ensure you are meeting the daily values for these nutrients, as this can help achieve optimal health and well-being, and may reduce the risk of obesity, type 2 diabetes, heart disease, osteoporosis, and certain types of cancer (Stiver, 2020).
