What is Nutrition

Nutrition is the science that interprets the interaction of nutrients and other substances in food about the maintenance, growth, reproduction, health, and disease of an organism. Includes intake, absorption, assimilation, biosynthesis, catabolism and food excretion.

Our bodies depend on six essential nutrients found in food: carbohydrates, fats, proteins, vitamins, minerals, and water.


Carbohydrates are the most major source of energy in the body. Carbohydrates are organic compounds that are simple or complex. Simple carbohydrates are sugars found in fruit (fructose), milk (lactose) and table sugar (sucrose). Complex carbohydrates are commonly known as vegetable starches found in bread, beans, rice, potatoes, vegetables, fruits and pasta.

Most of the calories you consume every day should come from complex carbohydrates. Simple carbohydrates are sugars. Complex carbohydrates are usually whole foods (grains, vegetables, legumes) with valuable nutrients and fiber.


The fat (lipids) provides insulation for the body and filling around the internal organs. Some fat in the diet is needed as a source of essential fatty acids for fat-soluble vitamins. Several nutrients are found in fat, including vitamins A, D, E, K and necessary fatty acids. Fats are essential in our diet, mainly triglycerides, and cholesterol. Triglycerides are the main way fats store in the body.

Fats are saturated or unsaturated. Saturated fats have been linked to heart disease and raise the level of cholesterol in the blood. This is the kind of fat you do not want to eat. Some plant foods contain saturated fats such as nuts, coconut oil and chocolate. Saturated fats and cholesterol are found in foods of animal origin such as butter, cheese, red meat and animal fat. The combination of too many saturated fats and cholesterol is bad for you. Cholesterol is produced in the liver of animals and is found only in foods of animal origin.

Unsaturated fats in small amounts are better for you than saturated fats. Unsaturated fats are found mainly in oils such as corn, cottonseed, olive, peanut, safflower, sesame, soybean, and sunflower.


Proteins help muscle tissue development and function. The protein is necessary to produce hair, skin, nails, muscles, organs, blood cells, nervous, bone and brain tissues, enzymes, hormones, and antibodies. Proteins and amino acids are found in both plant and animal foods. Amino acids are the building blocks for proteins.


Vitamins are complex organic compounds that are found in small amounts in most foods. Vitamins do not include calories and therefore do not provide energy. However, vitamins are important for metabolism and for our organs to work properly. Vitamins C, folic acid, and all B vitamins are soluble in water. Water-soluble vitamins leave the body in the urine. They do not accumulate and damage the body. Vitamins A, D, E, K are liposoluble. They are stored in fat cells. Too many of these vitamins in our system can lead to toxic buildup.


Minerals do not contain calories, but they are important for many bodily functions. There are two groups of minerals: main minerals and trace minerals. The main minerals include calcium, phosphorus, magnesium, potassium, sulphur, and sodium. Those minerals found in a variety of foods that include milk, meat, poultry, fish and green leafy vegetables. Trace minerals are needed in small amounts: they include iron, zinc, manganese, copper, iodine, and cobalt. Trace minerals are found in seafood, shellfish, whole grains, and legumes. Minerals often work together. Too much of a mineral can alter the balance of other minerals.


All food provides calories. All calories produce energy. However, calories that do not occur with vitamins, minerals, fatty acids, amino acids, and fiber.Empty calories give you energy without nutrients. Table sugar and alcohol are examples of empty calories. Eating too many foods with empty calories can cause health obstacles.

That is why it is essential to learn to choose foods that provide nutrients and calories. All calories, no matter where they come from, give you energy. If you eat more energy than you spend (burning during exercise) you gain weight. If you consume less energy than you spend, lose weight.

Which foods have the most calories?

– One gram of protein has four calories

– One gram of carbohydrates has four calories

– One gram of alcohol has seven calories

– One gram of fat has nine calories

Carbohydrates and proteins are better sources of nutrients and have less than half the fat calories. That’s why high-fat foods are also high in calories.


Water is important for other nutrients to work. We can survive for weeks without food, but we only live a few days without water. Water has no calories and does not provide energy. However, it has a key role in metabolism, particularly in the regulation of body temperature. Our main source of water comes from fluids. Water, soda, milk, coffee, juice, and tea provide inorganic sources of water. Solid foods, such as lettuce, celery, melons, and most fruits contain organic sources of water.For more information visit this site