Notes 3/4/13 - 3/8/13

Monday's Notes on Calories

Tuesday's Notes on Carbohydrates

Definition – organic macromolecules that contain carbon, hydrogen, and oxygen in the ratio of C_nH_2nO_n

Role – primarily to store energy – in some cases structure

Examples – monosaccharides - glucose – seldom found in food but used as body’s fuel

Fructose – very sweet, occurs naturally in fruits/veggies

Galactose – rare in food, found in lactose (milk sugar)

Disaccharides – sucrose – table sugar (glucose + fructose)

Lactose – sugar in milk (glucose + galactose)

Maltose – product of starch breakdown (glucose + glucose)

Oligosaccharides – short chains of carbohydrates – found in dried beans, peas, lentils, human milk

Polysaccharides – long chains of carbohydrates – starch (grains (wheat, rice, corn, oats), legumes (peas, beans, lentils) and tubers (potatoes and yams)).

Glycogen – animal starch, used to store carbs in liver and muscle

Fiber – carbs from plants that cannot be digested – ex. cellulose

Excess – extra energy is stored as glycogen and then fat typically – increased weight gain is associated with a variety of maladies – type 2 diabetes, heart disease

Deficiency – without the energy from carbohydrates, your body will use your protein and fat stores for energy – your brain only runs on glucose so different sources (ex. fat) must be converted to glucose – w/o carbs your liver cannot completely break down fat and produces ketone bodies – your cells can run on these but if they build up it can lead to ketosis making your blood dangerously acidic (and you can hallucinate)

Wednesday's Notes on Proteins

Definition – organic macronutrients made of amino acids (which contain C, H, O, N, sometimes others) – proteins have a 3D shape that determines their ability to function

Roles and examples– structure – ex. collagen, keratin

movement – ex. actin, myosin

enzymes – ex. amylase, lipase

hormones – ex. insulin

immune system – ex. antibodies

fluid balance – proteins in blood help attract fluid from in between cells

energy source – 4 kcal/gram

transport – help substances move into/out of cells

Sources – plants (legumes – ex. lentils, peas, soybean, tofu, grains, veggies, nuts) and animals (chicken, beef, pork, etc.) – animal protein is typically higher quality than plant protein (more variety of amino acids in proper proportions)

Excess – kidneys excrete protein normally so more protein can strain the kidneys – can also lead to loss of minerals like calcium – higher intake is associated with higher rates of obesity, heart disease, cancer, and osteoporesis

Deficiency – kwashiorkor – lack of protein – leads to edema (fluid in limbs), decrease in height/weight, dry/flaky skin, sores, brittle hair

Marasmus – lack of calories and protein – leads to wasting (loss of muscle and fat), drops in BMR, body temp., and a halting of growth

Thursday's Notes on Fats

Definition – organic molecules that dissolve in organic solvents like alcohol or acetone (non-polar, but not water (polar) – composed of fatty acids (carbon chains of varying lengths) -

Saturated fatty acids – fully loaded with hydrogen (no double bonds) – long chains are solid at room temp. while short chains are liquid

Unsaturated fatty acids – have one double bond (C=C) – liquid at room temp.

Polyunsaturated fatty acids – have multiple double bonds – liquid at room temp.

Trans fatty acids are a type of unsaturated fatty acid

Triglycerides – three fatty acids attached to a glycerol

Roles and examples –

energy source

energy reserve – adipose tissue

insulation/protection

carry fat soluble compounds – ex. vitamins

make up cell membranes and hormones

Sources – cheeses, milk, animal proteins, oils, nuts

Excess – diets high in fat, saturated fat, and trans fat increase the risk of heart disease and several types of cancer

Deficiency – possible issues with mood (depression) and concentration – problems absorbing fat-soluble nutrients (A,D,E, and K)