Summary
A balanced diet supplies carbohydrates, proteins, fats, vitamins, minerals, fibre and water.
In depth
Macronutrients: carbohydrates, proteins, fats; micronutrients: vitamins and minerals; fibre and water. Energy needs depend on age, size and activity. Malnutrition includes undernutrition and obesity.
Energy needs come from macronutrients; essential amino acids and fatty acids must be eaten. Food labels give nutrient content. Overnutrition raises disease risk.
Remember: fibre aids digestion though not digested.
Energy comes from carbohydrates and proteins (about 17 kJ per gram), fats (37 kJ) and alcohol (29 kJ). Dietary guidelines recommend about 45 to 65 percent of energy from carbohydrates (mostly complex), 20 to 35 percent from fats (limit saturated and trans), and 10 to 35 percent from protein. Essential amino acids and fatty acids must be eaten. Fibre aids bowel health and may reduce risk of heart disease and some cancers.
Malnutrition includes undernutrition (kwashiorkor, marasmus, stunting) and overnutrition (obesity, type 2 diabetes). Micronutrient deficiencies such as iron, iodine, vitamin A and zinc affect billions. Body mass index is a screening tool, with limits. Food labels, portion size and processing matter.
Example: scurvy results from vitamin C deficiency, and rickets from vitamin D.
Frequently asked questions
What is Nutrition and Diet?
A balanced diet supplies carbohydrates, proteins, fats, vitamins, minerals, fibre and water.
Which area of biology covers Nutrition and Diet, and how advanced is it?
Nutrition and Diet is one of the 51 topics in Human Physiology. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Energy Balance and Metabolism, Diabetes Mellitus, Digestive Enzymes.
Can you give an example of Nutrition and Diet?
Kwashiorkor is severe protein deficiency.
What should I learn before Nutrition and Diet?
Nutrition and Diet is a Beginner topic, so no earlier topic is required. Other Beginner topics in Human Physiology that pair well with it include Homeostasis, Tissues and Organs, Skeletal System.
What topics are related to Nutrition and Diet?
The closest topics to Nutrition and Diet are Energy Balance and Metabolism, Diabetes Mellitus, Digestive Enzymes, Small Intestine Absorption. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Nutrition and Diet?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Nutrition and Diet. To practise the whole of Human Physiology, use the Human Physiology quiz.
How is Nutrition and Diet different from Energy Balance and Metabolism?
Nutrition and Diet: A balanced diet supplies carbohydrates, proteins, fats, vitamins, minerals, fibre and water. Energy Balance and Metabolism: Body weight reflects the balance of intake and expenditure, with leptin and ghrelin regulating appetite. Read both side by side and note what each one explains.
How should I study Nutrition and Diet step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Energy Balance and Metabolism and explain the difference aloud. Finally, take the Human Physiology quiz and come back to this page for any question you miss.