What are nutrients?
Substances in food that provide energy and structure to the body and regulate body processes
What are the 6 classes of nutrients?
Carbohydrates, fats (lipids), proteins, vitamins, minerals, and water
What are essential nutrients?
Nutrients that are needed in the diet because the body cannot make them or the body can not make them in sufficient amounts
What classes of nutrients are essential?
All 6 Classes!
What are the functions of nutrients?
Energy, structure and regulation
How do nutrients provide energy?
Energy is the fuel our cells use to do work
How do nutrients provide structure?
Structure is the muscles, bones, water, tendons, etc.
How do nutrients provide regulation?
Regulation is the body temp, blood pressure, hormones, etc.
What are inorganic nutrients?
They do not contain carbon as a part of their chemical structure
What are examples of inorganic nutrients?
Water and minerals
What are organic molecules?
They contain carbon as a part of their chemical structures
What are examples of organic molecules?
Carbohydrates, proteins, fats, and vitamins
What are macronutrients?
They are nutrients found in large amounts in food and needed in larger amounts in the body. Requirements are measured in grams
What are examples of macronutrients?
Carbohydrates, proteins, fats, and water
What are micronutrients?
They are found in small amounts in food and needed in smaller amounts in the body. Requirements are measured in milligrams and micrograms
What are examples of micronutrients?
Vitamins and minerals
What are energy yielding nutrients?
Nutrients that when metabolized are converted to ATP (energy). they provide Calories = Energy
What are examples of energy yielding nutrients?
Carbohydrates, Proteins, and Fats
How many calories/gram from carbohydrates?
4 cal/gram
How many calories/gram from proteins?
4 cal/gram
How many calories/gram from fats?
9 cal/gram
What is the main role of carbohydrates?
Providing energy to the body
What is the main role of proteins?
To help make enzymes
Do vitamins provide energy?
No
What is nutrient density?
A measure of the nutrients provided by a food relative to its Caloric content.
What is an example of nutrient density?
Choosing a cup of blueberries (low cal, high nut) instead of choosing a can of soda (high cal, low nut)
What is caloric density?
A measure of the Calories a food provides relative to the amount of food (Calories per gram)
How do you make your diet healthy?
By choosing nutrient dense foods
What are foods?
Products derived from plants or animals that can be taken into the body to yield energy (ATP) and nutrients for the maintenance of life and the growth and repair of tissues
What are phytochemicals?
Substances found in plant foods that are not essential nutrients but may have health-promoting properties (i.e. flavonoids, carotenoids, and phytoestrogens)
What are zoochemicals?
Health-promoting substances found in animals (i.e. creatine)
Are phytochemicals and zoochemials nutrients?
No
What is fortification?
The addition of nutrients to foods
Why did we begin fortifying foods?
To help eliminate nutrient deficiencies in the population, with the federal government mandating that certain nutrients be added to certain foods
What are some government mandates for fortification?
Vitamin D be added to milk
B vitamins added to grains
Various vitamins added to breakfast cereals
What is Enrichment?
A form of fortification where nutrients are added back into foods that had lost them during processing
What is an example of enrichment?
Adding synthetic vitamins and minerals back into white flour after it has been processed
Why can food fortification be important?
Because lots of people suffer from vitamin and nutrient deficiencies
What is the problem with fortified foods?
Foods that are fortified are processed foods that are not healthy to begin with and adding nutrients to them doesn’t make them healthy
What helps combat micronutrient deficiency?
Fortification
What are functional foods?
Contain physiologically active compounds that provide health and benefits beyond their nutrient contributions (functional foods = foods that are fortified)
What are examples of functional foods?
Foods with added omega-3, probiotics, or calcium
Why are foods considered functional?
They contain substances such as phytochemicals that have been shown to provide benefits to our health (i.e. green tea, dark chocolate, and blueberries)
What are functional foods also called?
Neutriceuticals or super foods
What is the chemical composition of nutrients?
4 main elements: carbon, hydrogen, oxygen, and nitrogen
How many bonds can carbon form?
4
How many bonds can Nitrogen form?
3
How many bonds can Oxygen form?
2
How many bonds can hydrogen form?
1
What determines the amount of bonds an element can form?
The number of unpaired electrons each element carries
What elements are in Carbohydrates?
C, H, and O
What are the different types of carbohydrates?
Simple and complex carbohydrates
What are simple carbohydrates?
Sugars: monosaccharides and disaccharides
What are complex carbohydrates?
Starches and fibers
What are monosaccharides?
Simple sugars (carbohydrates) like glucose, galactose and fructose
Glucose
monosaccharide that is in blood sugar; also found in dextrose solutions and various sweeteners
Galactose
monosaccharide found mostly in milk and milk products
Fructose
monosaccharide that is the sweetest sugar; occurs naturally in fruits and honey
What are disaccharides?
Simple carbohydrates (sugars) made up of pairs of the 3 monosaccharides, maltose, sucrose, and lactose.Found naturally in the foods we eat.
Maltose
disaccharide composed of glucose + glucose (found in barley)
Sucrose
disaccharide composed of fructose + glucose (found in fruits, vegetables, grains, and table sugar)
Lactose
disaccharide composed of galactose + glucose (main CHO in milk)
What are complex carbohydrates?
Polysaccharides, which are made of many monosaccharides linked together
Glycogen
polysaccharide, the storage form of glucose in animals (incl humans). it is many glucose molecules linked together in highly branched chains.
Where is glycogen stored?
In the muscles and liver
Starch
polysaccharide, the storage form of glucose in plants (potatoes, bread etc)
Fiber (cellulose)
polysaccharide, structural parts of plants. Found in all plant derived foods (fruits, vegetables, grains, and legumes) not a form of storage, gives structure to plants
2 categories of fiber
Soluble and insoluble
Soluble fiber
Dissolves in water, forms gels, and is easily digested by bacteria in the colon (fermented)
What are food sources of soluble fiber?
Barley, oats, legumes, citrus fruits
What are benefits of soluble fiber?
Help protect against heart disease by lowering blood cholesterol and protect against diabetes by lowering blood glucose levels
Insoluble fibers
Do not dissolve in water, do not form gels, less readily fermented
What are food sources of insoluble fiber?
Whole gains (bran) and vegetables
What are benefits of insoluble fiber?
Promote bowel movements and alleviate constipation
What are lipids?
A group of organic substances that are insoluble in water.
What are the three main types of lipids in human nutrition?
Triglycerides, phospholipids, and sterols
What are triglycerides?
How fats occur in foods and how we store fat in the body
What is the structure of a triglyceride?
3 fatty acids attached to a glycerol (an alcohol)
What is a fatty acid?
An organic compound composed of a carbon chain with hydrogen atoms attached and an acid group (COOH) at one end and a methyl group (CH3) at the other end
How do most fatty acids naturally occur in the body?
Containing even numbers of carbons in their chains up to 24 carbons in length.
Short chain FA
Less than 6 carbons, found in dairy products
Medium chain FA
6-10 carbons, found in dairy produce and coconut oil
Long chain FA
12-24 carbons, seen in FA’s of meats, fish, and vegetable oils; are the most common in the diet
What are saturated FA’s?
FA carrying the maximum number of hydrocarbon atoms and containing only single bonds between its carbons (along the carbon chain)
What are unsaturated FA’s?
Lack hydrogen atoms and have at least one double bond between carbons. The double bond is a point of unsaturation
Monounsaturated vs. Polyunsaturated FA’s?
Mono have 1 double bond, poly have 2 or more double bonds
Omega 3 and Omega 6 FA’s?
Chemists identify PUFAs by the position of the double bond nearest the methyl (CH3) end of the carbon chain, which is described by an omega number (used to refer to the position of the first double bond)
What two FA’s can the body not make but needs?
Alpha-linolenic acid (omega-3) and linoleic acid (omega-6)
Why can’t cells make omega-6 or omega-3 FA’s?
The cells don’t have the enzymes to make any because the body cannot insert double bonds before the 9th carbon from the omega (methyl) end. The body cannot convert omega-6 to omega-3 or vice versa