is called pernicious anemia due to lack of cobalamin (b12)
parasitic - fish tapeworms
bugs make these in guts, so never primary disorder
What causes B6 (pyridoxine) deficiency?
associated with alcoholism
In blood, smear, how would megaloblastic anemia cells look different from normal cell?
cells are larger
cells have segmented nuclei
in addition to folate, B6, or B12 deficiency megaloblastic anemia is also associated with what 4 things?
ethanol (most common)
How are the tissues of oral cavity a sensitive indicator of adequate nutritional status?
these soft tissues have epithelial cells that have rapid rates of replication, metabolism and differentiation
requires steady supply to nutrients
cell turnover every 3-7 days
What is Vitamin A necessary for?
necessary to form retinal, part of the rhodopsin
What happens in deficiency of Vitamin A?
Deficiency causes night blindness (mild)
to total loss of sight (severe)
skin lesions in the eye causes keratomalacia (cornea thinning, cell taking over) and appearance of Bitot's spots (reversible)
What is the advantages of Vitamin A?
decreased resistance to infections
What is Vitamin D needed for?
required for bone mineralization
What disease is associated with deficiency of Vitamin D?
Rickets - deficiency in children that results in a failure to mineralize osteoid matrix (in young)
osteomalacia - deficiency in adutls that results in decreased appositional bone growth (in adults)
can cause increased incidence of colon and prostate cancer
What is vitamin E also known as?
What does Vitamin E do?
tocopherols act as anti-oxidants and decrease the peroxidation of fatty acids
Deficiency of Vitamin E leads to what? and how does that occur?
deficiency is associated with mild anemia and spinocerebellar ataxia (hard time coording arm and leg movement)
mutations in the gene encoding vitamin E binding protein-tocopherol transfer protein (TTP) -> ataxia
Vitamin E is most commonly as secondary disorder associated with what?
a fat malabsorption syndrome
What is Vitamin K also known as?
What is Vitamin K needed for?
required for production of specific clotting factors (factors II, VII, IX, and X)
Deficiency in Vitamin K is characterized by what?
by elevated clotting times principally due to low prothrombin
How does deficiency in Vitamin K occurs in adult vs. newborns?
adults - occur as 2ndary disorder since Vit K is produced by normal intestinal bacteria. associated with use of some disease
newborns - occur because placental transfer is poor, breast milk is low in vit K, and the GI tract is nearly sterile. Normal platelet count, elevated prothrombin time (PT) and elevated partial thromboplastin time (PTT)
What is thiamine also known as?
Classic deficiency of thiamine is know as what? What are the subclasses for that and what is it?
1. "dry" - involves nervous system damage
2. "wet" - associated with cardiomyopathy
what is the characteristic of deficiency in thiamine/B1?
by peripheral neuropathy that affects sensation particularly in legs (associated with demyelination of peripheral nerves)
what is the syndrome in severe cases of Thiamine/B1 deficiency?
Korsakoff syndrome - edema and cardiomyopathy can occur
characterized by impaired ocular motility, ataxia, mental confusion
When thiamine deficiency is suspected, what does that patient take?
usually all soluble vitamins because if one B vitamin is missing, most likely the others are too
What is another name for niacin?
What is the classic deficiency of niacin?
pellagra = rough skins
What is niacin most commonly associated with?
What are the symptoms for Niacin deficiency?
3 D's - dermatitis, diarrhea, and dementia
hyperkeratosis and vesiculation of skin (skin on neck, chest and back of hands can become brown and scaly)
nausea, vomitting, and diarrhea
insomnia, depression, confusion, and rapid mood change
What is vitamin B12 also known as?
where is B12/cobalamin found?
widely distributed in foods
also produced by intestinal bacteria
Deficiency in Vit B12/cobalamin results in what?
spinal cord sclerosis - thickening of spinal chord
atrophy of mucous tissues
How is Vit B12/cobalamin taken up?
taken up from GI tract by proteinc alled intrinsic factor
associtead with gastric atrophy and decrease in intrinsic factor mediated uptake
decreased absorption in elderly ppl -> reduced tissue B12 levels
What is Vit C also known as?
What is the classic deficiency of Vit C/ascorbic acid?
what is Vit C/ascorbic acid required for?
for maturation of collagen
Deficiency in Vit C/ascorbic acid leads to what?
in an inability to produce mature collagen -> Connective Tissue disorder
inability to synthesize osteoid and dentin
decreased wound healing and loss of blood vessel wall integrity
fatigue, purpura, dermatitis - in severe cases oral lesions
What is B6 also known as?
What is a deficiency that is associated with B6/pyridoxine?
Severe case of B6/pyridoxine deficiency lead to what?
to a peripheral neuropathy
For B6/pyridoxine, are primary deficiency rare? If it is, what is more common?
subclinical deficiencies more common
Other vitamins, such as B2 and biotin are associated with deficiencies but they less likely to have important roles in overt clinical deficiency syndromes.
other major minerals are what?
What happens when there's too little of iodine?
hypothyroidism and goiter
What is calcium needed for? too much calcium causes what? too little calcium causes what?
needed for: bone mineralization
too much: bone loss observed in elderly
too little: increased risk of periodontal disease
Deficiency in iron causes what?
trace elements are required for...
normal development and metabolism
What are the trace elements?
deficiency in zinc originally described in pts receiving....
total parenteral nutrition
Zinc deficiency can be secondary effect of what 2 things?
zinc deficiency is characterized by?
Copper deficiencies are associated with what?
severe malabsorption syndromes or total parenteral nutrition
Copper deficiency resembles what?
iron deficiency anemia
Fluoride levels in drinking water great than ____ can cause _____.
chronic fluorosis can produce what?
abnormal calcification of tendons and ligaments
What is the dilemma regarding RDA?
RDA is the recommended amount
many adults in US receive less than RDA for variety of vitamins and minerals but do not exhibit over deficiency symptoms
research have shown that vitamine supplements don't harm and don't help
what is hypervitaminosis?
too much a certain vitamin
Too much of vitamin A causes what?
both acute and chronic effects
intake 6-7 times the RDA
decreased growth, bone pain, liver damage (fatty change)
too much of Vitamin D causes what?
chronic effects include abnormal calcification in heart and kidney
too much vit E causes what?
elevated serum lipids and depressed thyroxine (rare)
main effect: antagonize vitamin K (increased bleeding times)
What are the water soluble vitamins?
folic acid pyridoxine
*can just go out in urine
what happens with too much nicotinic acid?
itching & skin rashes
some altered liver function
too much thiamine causes...
when injected, causes hypersensitivity rxn at site of injection
Too much vit C causes what?
GI disturbances & skin rash (very rare)
too much folic acid causes what?
too much pyridoxine causes what?
Second leading actual causes of death in US is what?
Diet/activity - 28% (after tobacoo 39%)
What are the problems associated with determing the contribution of specific dietary constituents to a disease?
1. control - in most nutritional studies, there are no unexposed controls.
2. multiple variables - some nutrients are highly correlated (co-correlated)
3. animal studies a. rarely duplicate the nutritional status of humans b. are real physiological differences between species c. must compress what happens in years to weeks or months
4. accurate reporting - human diets are complex and constantly changing. we can't remember what we eat to have meaningful details
What kind of study is helpful for nutritional studies?
What are main known environmental causes of human cancers?
dietary imbalances (excess fat and calories)
An increased risk of what type of cancers is related to obesity and/or dietary fat ?
There does NOT appear to be a clear and simple relationship between dietary fiber and colon cancer
There is a general relationship between fat intake and overall age-adjusted death rates in different cultures. take home message is...
reduce fat in your diet!!!
Differences between carcinogens and mutagens
carcinogens - causes cancer and takes a long time to tests w/ lots of $$$
mutagens - can become agents that causes cancer. quicker and cheaper
Humans use lots of additives. Nitrates are used as preservatives in meat. How can that be carcinogenic?
can be converted to nitrosoamines -> carcinogenic
Where do we see carcinogens and mutagens in food?
1. food additives
2. naturally occuring
3. resulting from storage, processing, or cooking
Improperly stored grains and nuts can accumulate mold metabolites known as what?
aflatoxins - 1 of the most potent carcinogens
high temp during cooking can convert natural metabolites into what?
heterocyclic amines (HCAs) = mutagenic
co-correlation between meat consumption and what?
colon cancer risk
epidemiological evidence for relationship btw intake of highly salted foods and what?
high in Japan
What is the relationship between vitamins and chemoprevention?
The rationale of using vitamins as anti-oxidant and anti-carcinogens
however, most shows no beneficial effect on cancer risk
phytochemicals as dietary factors in chemoprevention?
yes, relationship between plant constituents and decreased cancer risk
some specific compounds - carotenoids, terpenes, indoles, soy isofalvones, polyphenols, organosulphur compounds
what is the equation on how to calculate body mass index (BMI)? Does not work for those who are...
value of 25-27 - increase health risk
more than 30 - obese
overestimates fatness in muscular or athletic ppl
not good for adolescents or children
statistical relationship between being overweight and decreased longevity. what is obesity?
men: >25% body fat
women: >30% body fat
what are the diseases associated with obesity (7) ?
High fat diets are risk factor in atherosclerosis. Recommended amount of dietary fat is what?
no more than 30% of total caloric intake
what is clearly a risk factor in atherosclerosis?
high serum cholesterol levels
relationship between dietary cholesterol intake and serum cholestero is not direct cuz of hepatic cholesterol
What is the relationship between alcohol and chronic heart disease?
drinking too much alcohol increases heart disease risk
moderal - lowers risk
does not recommend nondrinkers start using alcohol or that drinkers increase amount they drink
Evidence of high carb diets are associated with increased risk of heart disease. The most important factor is what?
low carb diet consume fewer total calories in recent study
dietary sucrose is directly related to incidence of what?
dental caries but apparently not periodontal disease
Is there validity to Halloween effect?
no, in controlled studies, there's no direct effect of sugar high in children
What is the effects of TFAs or trans fatty acids?
increases LDL cholesterol levels and decrease HDL cholesterol levesl
responsbile for lots of premature coronary deaths each year
Very high levels of niacin supplements have been shown to do what?
reduce serum cholesterol and triglycerides in many ppl
What is the effects of n-3 PUFA - omega 3(n-3) fatty acids?
increase HDL cholesterol
decrease plasma triglycerides
reduce reactivity of platelets, monocytes, and neutrophils
reduce blood pressure
have antiarrhythmic properties
Too much dietary sodium can be bad. There is a direct relationship between sodium and what?
In Japan, what is the leading cause of death and why?
average daily intake of sodium of 20gm/day (compared to recommended of 6 gms/day)
What is the genetic factor of sodium and hypertension?
about 30% of ppl in US is sensitive to dietary sodium so they are recommended to take less
Who should NOT be on low sodium diets?
those who do not produce enough ADH - adrenal insufficency