Human Nutrition

Nutrition

the science that studies food, beverages, etc. in biological systems, like digestion, absorption, metabolism and impact on health

Nutrient

a substance that performs a necessary function in the body

Macronutrient

various types of nutrients needed in larger amounts for the body:

1. carbohydrates

2. lipids

3. water

4. proteins

Micronutrient

types of nutrients needed in smaller amounts for the body. Just as important as macronutrients:

1. minerals

2. vitamins

Carbohydrates

Carbon + Hydrogen + Oxygen. Types of carbohydrates:

1. Monosaccharides

2. Disaccharides

3. Polysaccharides

Glucose

primary energy source. Most carbs get broken down into glucose.

Monosaccharide

also known as simple sugar, provides one unit of sugar:

1. glucose

2. fructose

3. galactose

Disaccharides

also known as double sugar, provides 2 units of sugar:

1. lactose

2. sucrose

3. maltose

Polysaccharide

also known as complex sugar, is a long chain of sugar molecules:

1. cellulose

2. starch

3. glycogen

glycogen

a stored form of glucose. When the body needs more energy, glycogen turns back into glucose to be used.

Proteins

• carbon + hydrogen + oxygen + nitrogen

• each protein is organ specific

Amino acids

organic building blocks that make proteins. There are 20 kinds that can be arranged into thousands of proteins. 11 the body can make itself, the others you get by eating food.

Protein functions in the body:

1. growing, repairing and maintaining body tissues

2. form structural components of soft tissues and hard tissues

3. regulate fluid balance

4. electrolyte transport

5. acid-bace balance

6. can provide energy but main function is structural and regulatory

Marasmus

a protein and energy deficiency resulting from starvation

Kwashiorkor

a lack of protein in the diet, usually seen in young children after weaning

deamination

the process by which excessive amino acids are converted to urea by separating the nitrogen containing amine group

Lipid

a naturally occurring chemical compound that cannot be dissolved into water. There are different kinds of lipids

Triglycerides

• most common type of fat in body/food

• glycerol + 3 fatty acids

• supplies energy, protects against temperature extremes and shock, helps the body use carbohydrates and protein efficiently

Glycerol

type of alcohol

fatty acid

an organic compound linking a fatty chain of carbon and hydrogen atoms on one end to an acid group at the other

Fats

• the form in which energy is stored in the body

• provides more than 2x the energy of carbohydrates and proteins

• provides linoleic and linolenic acids

• gives the body it’s shape and insulates it, assisting in the body temperature

Linolenic and linoleic acid

an essential polyunsaturated fatty acid you can get from plant-based oils, nuts and seeds. It assists in absorbing and transporting fat soluble vitamins A,D,E,K

Water

• made from hydrogen + oxygen

• our most urgent nutritional need

• the only macronutrient that doesn’t provide energy

Vitamins

compounds we have to get from food that are very important and help almost every chemical reaction in our bodies

Vitamin C

• helps protect cells from damage

• needed to form blood vessels, cartilage, muscle and collagen

• helps the body with healing

Collagen

a protein that’s the primary building block for skin, muscle, bones, tendons and ligaments. It provides structure, strength, support and elasticity

Vitamin K

helps your body with blood clotting and the building of bones.

Vitamin B12

helps your body in making healthy nerve cells, red blood cells and DNA

Minerals

chemicals the body needs to function properly. They come entirely from the earth and always retain their chemical identity. There are major minerals and trace minerals.

Major minerals

required in higher amounts in the body:

1. Magnesium

2. Sulfur

3. Sodium

4. Chloride

5. Calcium

6. Potassium

7. Phosphorous

Trace minerals

required in smaller amounts for the body:

1. Iron

2. Manganese

3. Zinc

4. Chromium

5. Copper

6. Molybdenum

7. Flourine

8. Iodine

9. Selenium

Calories

also known as kilocalories (kcals) Its how the amount of energy in food/drink is measured. It’s the amount of energy needed to raise 1 kg of water by 1 C.

Phytochemicals

natural compounds you can find in plants that may help protect against diseases

Functional food

a food/food ingredient that can provide benefits beyond the macro and micronutrients it contains

Epidemiology

branch of medicine which deals with the incidence, distribution and possible control of diseases and other factors relating to health. Types of epidemiological studies:

1. Cross-sectional studies

2. Case-control studies

3. Prospective cohort studies

Zoochemicals

natural compounds you can find in animal-based foods, that may help protect against diseases

Cross-sectional studies

compares different populations at the same point in time

Case-control studies

looks at a group of cases vs. controls. Most of these studies are retrospective. They try to determine if there were differences in the diets of the cases compared to controls in the past

Cases

people with a disease

Controls

people without the disease. Researchers choose a control who has similar characteristics to the case. Then they compare exposure levels between case and control.

Cohort

a group of subjects

Prospective cohort studies

initial information is collected on the intake of a cohort of people at baseline. The cohort is then followed over time to quantify health outcomes of the individual within it.These studies are more accurate than case-control studies because you do not start with diseased people and people don’'t need to remember their diet before they got a disease.

In vitro

(within glass) the simplest form of nutrition research, which is performed within a test tube, dishes or elsewhere outside of a living organism.