Proteins Flashcards
From Encyclopedia of Healing Foods
Most plentiful component in body after water
Protein
Proteins make up
hair, muscles, nails, tendons, ligaments, and other body structures
Proteins also function as
enzymes, hormones, and components of other cells such as genes
Human body contains between ____ and ______ unique proteins
30000 and 50000
Building blocks of proteins
amino acids
during a single day, how much protein is broken down into amino acids and reassembled into new proteins
about a pound of an adult’s body protein
Protein turnover allows us to
grow, heal, remodel, internally defend ourselves on a continual basis
Amino acids our body can’t make
Essential amino acids
RDA for protein is based on
bodyweight
RDA requirement for protein is
.36g per lb
Conditions that require more protein
childhood/adolesence, pregnancy, lactation, intense strength and endurance training, elderly, and some diseases such as AIDS and cancer
High protein diet requirements
.8g per lb
Negative effects of high protein
excess protein can become burden for kidney and liver
increases use of amino acids as a daily energy source, which decreases the breakdown and utilization of fat for energy = increased body fat
Two most common forms of protein deficiency
marasmus & kwashiorkor
Marasmus
mainly in infants under 1 yr old who are weaned off breastfeeding into a diet that is too few calories or too little protein
Child becomes severely underweight, weak, lethargic
Kwashiorkor
often in older children who have been weaned onto a diet high in starchy foods but a diet still too low in calories and protein
severely underweight, edema = face moon-shaped and arms and legs plump, thin discolored hair, patches of scaly skin and variable pigmentation
Amino acids compounds
compounds containing carbon, hydrogen, oxygen, nitrogen, and in some cases sulfur
All amino acids are made up of…
an acid group and an amino group attached to a carbon atom
Essential amino acids
9-10
- arginine, *histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine
- only essential during growth
Quality of a protein source depends on
level of essential amino acids, digestibility, and ability to be utilized by the body
Nonessential amino acids
Amino acids the body can produce itself
nonessential = not needed from foods
Peptide bond
link that connects amino group of one amino acid to the acid group or carboxyl end of another amino acid
forms a chain
Types of peptide bonds
Dipeptide- 2 amino acids
Tripeptide- 3 amino acids
Peptides- 4 to 10 amino acids
Polypeptids- greater than 10 amino acids
Proteins- very long links of amino acids (>100) and/or more than one linkage complexed together
Protein- peptide bonds
a typical protein may contain 500 or more amino acids joined by peptide bonds
each protein has its own specific number and sequence of amino acids
some smaller proteins exist as almost straight chain amino acids, but most are complex 3D pattern
Individual amino acids can also…
make certain hormones and neurotransmitters
Ex: epinephrine, serotonin, norepinephrine, thyroid hormone
can also make other substances like choline, carnitine, & nucleic acids in DNA
complete protein source
one that provides all 9 essential amino acids in adequate amounts
Ex: meat, fish, dairy, poultry
Incomplete plant sources
most plant foods, especially grains and legumes, lack one or more essential amino acids
can be combined to create complete
Plant based combinations for complete proteins
grains and legumes
grains and nuts/seeds
nuts/seeds and legumes
Biological value
the proportion of the amino acids that are absorbed, retained, and used in the body
Highest biological value protein
whey- natural byproduct of the cheese making process
second highest is egg
Whey protein
highest biological value protein
whey protein concentrate/isolate: 110-159
Whey protein: 104
made by filtering off lactose, fats, and minerals
contains all essential and nonessential amino acids
highest concentration of glutamine and BCAAs found in nature
mostly used by bodybuilders and athletes, also used to support recovery from surgery, prevent wasting syndrome of AIDS and cancer, offset neg effects of radiation, therapy, chemotherapy
Glutamine & BCAAs
critical to cellular health, muscle growth, and protein synthesis
Eggs
second highest biological value protein at 100
egg protein is often the standard by which all other proteins are judged
considered to be a nearly perfect food
Percent of protein from animal products in US vs plant sources
72% from animal sources, 28% from plant
of 72%- 40% from meat, fish, poultry, 18% from dairy, 4% eggs
of 28%- 18% grains, 8% fruits & veggies, 3% legumes
Risks of high amounts of animal protein
linked to *heart disease, cancers, *high blood pressure, kidney disease, osteoporosis, kidney stones
*associated with increased intake of animal fats as well as animal protein
Animal protein & cancer
cancer can be caused by proteins that are altered in some cooking processes such as grilling and blackening, and by action of gut bacteria on undigested protein
Animal protein & kidneys
too much protein can have damaging effect
Animal protein & osteoporosis and kidney stones
deal with calcium metabolism- a high protein diet increases the excretion of calcium in the urine
high protein diet a significant factor in increased number of people suffering from osteoporosis and kidney stones
Special amino acids
special interest in regard to growth and development, metabolism, protection from environmental chemicals as well as variety of diseases
Types of special amino acids
arginine, BCAAs, glutamine, lysine, methionine & cysteine, and taurine
Arginine
role in wound healing, detoxification reactions, immune functions, and promoting secretion of several hormones including insulin and growth hormone
has a relaxing effect on blood vessels, improving blood flow
body can usually make enough even when diet is lacking, but sometimes might need supplementation
Arginine foods
chocolate, peanuts, seeds, nuts like almonds & walnuts
Arginine & cardiovascular disease
beneficial for angina pectoris, congestive heart failure, high blood pressure, peripheral vascular insufficiency (decreased blood flow to legs or arms) because increases nitric oxide levels
Arginine and nitric oxide levels
increases
nitric oxide plays central role in regulating blood flow
arginine supplementation = increased nitric oxide = improved blood flow, reduced blood clot formation, improve blood fluidity
Arginine & interstitial cystitis
symptoms similar to UTI but no infection
since nitric oxide plays role in bladder function, studies have shown arginine can be helpful, but needs more research
Arginine and male infertility
effective to improve male fertility
If sperm count is less than 20 million per milliliter, arginine supplementation is less likely to be helpful
dosage of 4g a day for 3 months
Arginine of growth hormone secretion
promote secretion of growth hormone by pituitary gland, responsible for stimulating muscle and skeletal growth
generally accepted as true
used to gauge whether a child or adult is releasing enough growth hormone
not effective over age 65
BCAAs
leucine, isoleucine, valine
essential amino acids
maintenance of muscle tissue, preserve muscle stores of glycogen (storage form of carbs that can be converted into energy)
research on BCAA supplementation to enhance endurance performance are inconclusive
found in most high protein foods- dairy & red meat have highest amounts
Glutamine
most abundant amino acid in the body
involved in more metabolic processes than any other amino acid
most abundant amino acid in the blood and free amino acid pool of skeletal muscle
stimulates the synthesis and in habits the degradation of proteins and is an energy source for muscle cell division
precursor for synthesis of amino acids, proteins, nucleotides, glutathione, and other molecules
anabolic effect on skeletal muscle
source of fuel for cells lining the intestines
proper functioning of white blood cells
high protein foods generally = high glutamine; whey & eggs are very good sources
Glutamine & athletic performance
doesn’t improve performance but aids in recovery time of plasma glutamine levels
low glutamine = detrimental effect on athletic performance and muscle growth
supplements can boost levels and promote muscle protein synthesis
biggest benefit is prevention of infections
Glutamine & immune function
boost immune function & fight infection
shown in endurance athletes (extreme exercise suppresses immune system) and critically ill subjects- can dramatically increase survival in very ill patients
unknown if glutamine supplementation enhances immune function in healthy people
Glutamine & peptic ulcers
promotes healing of ulcers
more effective than conventional treatments such as antacids and antispasmodics
cabbage juice is high in glutamine and helps heal ulcers
Glutamine & chemo side effects
help prevent mouth ulcers (stomatitis), muscle and joint pain, and suppression of the immune system in cancer patients receiving some types of chemotherapy, most notable 5-fluorouracil and paclitaxel (taxol)
Lysine
essential
growth & bone development in children
calcium absorption and maintenance of the correct nitrogen balance in body
maintenance of lean body mass
production of antibodies, hormones, and enzymes
collagen formation and repair of tissue
Lysine benefits
high amounts useful for patients recovering from injuries or operations
help maintain healthy blood vessels
fighting herpes infections and cold sores
*arginine triggers herpesviruses and lysine blocks effects of arginine = antiviral activity
Lysine foods
high in lysine = most vegetables, legumes, fish, turkey, chicken
Methionine and Cysteine
interconvertible sulfur-containing amino acids
methionine = essential
cysteine = nonessential
health of connective tissue, joints, hair, skin, nails
detoxification reactions to excrete heavy metals
reduce bladder irritation by regulating formation of ammonia in urine
Foods = meat, fish, eggs, dairy
Methionine & SAMe
converted to S-adenosyl-L-methionine (SAM or SAMe)
compound involved in more than 40 biochemical reactions in body
works closely with folic acid & B12 in methylation reactions
Methylation
process of adding a single carbon unit (a methyl group) to another molecule
methylation reactions critical in manufacture of brain chemicals and detox reactions
SAMe
SAMe much more effective in transferring metal groups to other methyl donors
supplementation has positive results for depression, osteoarthritis, fibromyalgia, liver disorders, and migraine headaches
Taurine
sulfur-containing amino acid
produced from diet (nonessential) or produced from methionine and cysteine
Different because:
1. not utilized in protein synthesis, found unbound or existing in small peptide chains
- structure is different because a sulfur group replaces the carboxylic acid element found in other amino acids
regulator of cellular charge, maintaining cell membrane stability
regulates heartbeat, prevent brain cell overactivity, essential to visual process
Taurine supplementation
1-4g supplement per day = improve heart function in congestive heart failure, lower blood pressure, reduce seizures in people with epilepsy where drugs aren’t controlling it
Foods= highest in animal products
Tryptophan
essential
starting point in creation of serotonin and melatonin
serotonin
master control chemical
muscle movement, state of alertness, mental activity, ability to sleep depend on this
melatonin
primary hormone in sleep regulation
determines sleep-wake cycle/circadian rhythm
secreted from pineal gland as daylight begins to decline
potent antioxidant with protective effects against many types of cancer
adults tend to produce less as age
Tryptophan & serotonin/melatonin deficiency
poor diet, lack of exercise, caffeine, alcohol, stress = brain doesn’t make enough serotonin and melatonin to meet body demands
Tryptophan metabolism
main determinant is balance of other amino acids in the blood stream, which is determined by food in diet
found in foods in small amounts compared to other amino acids
Tryptophan and protein meal vs carb meal
high-protein meal= few hrs after, high levels of many different amino acids will compete for entry into the brain on few available transport molecules
high-carb meal= higher levels of tryptophan and lower levels of other amino acids, so tryptophan enters brain quickly and serotonin rises
same thing happens as in high-carb as when you eat foods high in tryptophan- turkey, milk, cottage cheese, chicken, eggs, red meats, soybeans, tofu, nuts (especially almonds)
