- Cobalamin (B12) - lack of intrinsic factor (PERNICIOUS ANEMIA), malabsorption, parasitic - fish tapeworms
B6 (pyridoxine) - alcoholism
In addition to folate, B6, or B12 deficiencies, megaloblastic anemia is also associated w:
ethanol (most common)
What are 2 other types of anemias NOT associated w nutritional disease?
hemolytic anemia (decreased RBC lifespan)
aplastic anemia (failure of marrow to produce new cells)
Describe the integrity of the oral mucosa
soft tissues of the oral cavity are made up of epithelial cells that have rapid rates of replication, metabolism, and differentiation which require a steady supply of nutrients
typically these cells turn over every 3-7 days
makes tissues of oral cavity a sensitive indicator of adequate nutritional status
T/F: In developed countries, primary dietary vitamin deficiencies are common and are probably under diagnosed.
False. In developed countries acute or primary vitamin deficiencies are rare and probably over diagnosed. Vitamin deficiencies are more commonly secondary disorders associated w malabsorption conditions and chronic alcoholism.
Describe Vitamin A deficiency
Vit A: retinoids; fat soluble compounds derived from B-carotene
- deficiency causes night blindness due to decreased rhodopsin. Also skin lesions (rash on extremities w punctate erythematous lesions) & Bitot's spots on eye
also decreased resistance to infections
Vit D deficiency
required for bone mineralization
Rickets- deficiency in children --> failure to mineralize osteoid matrix
Osteomalacia - deficiency in adults that results in decreased appositional bone growth
Increased incidence of colon and prostate ca
Vit E deficiency
Tocopherols - act as anti-oxidants and decrease the peroxidation of fatty acids
Occurs as secondary disorder in conditions w fat malabsorption (CF, pancreatitis, cholestasis (bile-flow obstruction))
causes neurological disorder characterized by sensory loss, spinocerebellar ataxia, and retinitis pigmentosa (due to free radical mediated neuronal damage)
mutations in gene encoding Vit E binding protein- tocopherol transfer protein (TTP) result in ataxia
Vit K deficiency
Phylloquinone - required for production of clotting factors (II, VII, IX, X)
characterized by elevated clotting times (impaired coagulation), principally due to low prothrombin
*Normal platelet count, elevated prothrombin time (PT), elevated Partial thromboplasin time (PTT)
In adults occurs as 2ndary disorder (associated w use of anti-coagulants, liver disease, celiac disease, pancreatic disease, obstructive jaundice)
Vit K produced by normal intestinal bact
In newborns deficiency can occur b/c placental transfer is poor, breast milk low in Vit K, GI tract is nearly sterile
peripheral neuropathy that affects sensation in legs (demylination of peripheral nerves)
in more severe cases of Korsakoff syndrome (impaired ocular motility, ataxia, mental confusion), edema and cardiomyopathy can occur
Nicotinamide, Vit B3
PELLAGRA- "rough skin"
Most commonly associated w alcoholism
Primary deficiencies associated w diets of a single, low quality protein source (ie corn)
In developed countries, associated w alcoholism
*3 D's: dermatitis, diarrhea, dementia -->
- hyperketosis & vesiculation of skin (skin on neck, chest, and back of hands become brown and scaly)
- nausea, vomitting, diarrhea
- insomnia, depression, confusion, and rapid mood change
widely distributed in foods & produced by intestinal bact, so deficiencies almost always secondary disorders associated w gastric atrophy (and decreased uptake via intrinsic factor), microbial proliferation (AIDS), long-term antacids, chronic alcoholism, idiopathic (age-related)
Primary clinical symptoms: pernicious anemia, polyneuropathy, sclerosis of spinal cord, atrophy of some mucous tissues (ie tongue papillae)
Ascorbic acid deficiency
required for maturation of collagen --> deficiency results in inability to produce mature collagen (CT disorder)
Inability to synthesize osteoid & dentin
decreased wound healing and loss of blood vessel wall integrity
fatigue, purpura, dermatitis --> in severe oral lesions
associated w megaloblastic anemia
severe cases lead to peripheral neuropathy
primary deficiencies rare, but sub-clinical deficiencies may be more common
*most commonly associated w Multivitamin B deficiencies in malnutrition and alcoholism
Name 4 elements that are required for life but dietary deficiencies do not develop
Hypothyroidism & goiter
essential for synthesis of thyroid hormones
required for bone mineralization
RDA for adults is 800 mg/day
doses above RDA in elderly delay bone loss
low dietary calcium associated w increased risk of periodontal disease
List 3 trace elements with overt deficiency syndromes and respective clinical symptoms
Zinc - deficiency in total parenteral nutrition; can be secondary to acrodermatitis enteropathica (autosomal recessive trait). Characterized by alopecia, dermatitis, diarrhea
Copper - deficiency associated w severe malabsorption syndromes or total parenteral nutrition. Resembles iron deficiency anemia and osteoporosis
Fluoride - levels greater than 1 ppm can cause mottling of teeth; chronic fluorosis can produce abnormal calcification of tendons and ligaments
What's the "RDA Dilemma"?
•Many adults in the US receive less than the RDA for a variety of vitamins and minerals but do not exhibit overt deficiency symptoms.
• Hundreds of retrospective studies have indicated some value for vitamin supplements, however.........
• Recent large prospective studies have so far not shown any health benefit for healthy individuals who take vitamin supplements.
Name 3 vitamins and their associated symptoms/impacts that are due to HYPERvitaminosis.
Vit A: acute & chronic effects; intake 6-7x RDA can produce decreased bone growth, bone pain, liver damage (hepatotoxicity) & vision changes
Vit D: hypercalcemia; severe cases - cardiomyopathy & renal damage associated abnormal calcification
Vit E: daily doses +800 IU cause elevated serum lipids (hypertriglyceridemia) and depressed thyroxine (rare). *main effect: antagonize Vit K (increased bleeding times)
What are some water soluble vitamins that may contribute to HYPERvitaminosis?
• Nicotinic acid - used in large doses to treat hypercholesterolemia; skin flushing, itching & skin rashes. Some altered liver function (requires hundreds of mgs)
• Thiamine - when injected, hypersensitivity reaction at site of injection
• Vitamin C - G.I. disturbances & skin rash (very rare); ppl w pre-existing cystinuria, oxalosis, or hyperuricemia can develop kidney stones
• Folic acid - may cause birth defects
• Pyridoxine - sensory neuropathy
Data suggests 30-50% of all human cancers are related to nutritional factors. Which cancers appear to be related to dietary fat and/or obesity?
** there does NOT appear to be a clear and simple relationship between dietary fiber and colon cancer**
What are some problems associated w determining the contribution of specific dietary constituents to a disease?
• Controls- epidemiologists have usually tried to associate exposure of a single variable compared with unexposed controls. However, in most nutritional studies there are no unexposed controls.
• Multiple variables- some nutrients are highly correlated (so- called co-correlates).
• Animal studies-
-rarely duplicate the nutritional status of humans
-are real physiological differences between species
-must compress what happens in years to weeks or
• Accurate reporting- human diets are complex and constantly changing. Most individuals cannot accurately recall meaningful details for any reasonable period of time – limits the usefulness of “controlled case studies”.
What is the association with additives in food and human cancers?
The only clear association between these substances and human cancer is the conversion of nitrates to nitrosamines (known carcinogens).
T/F: 99.9% or more of the chemicals we eat are natural. A wide variety of natural substances are known mutagens or can cause cancer in rodent tests.
Improperly stored grains and nutes can accumulate mold metabolites known as this.
Aflatoxins are among the most potent carcinogens that have been tested. Peanut butter can contain an average of 2 ppb aflatoxin.
High temps during cooking can convert natural metabolites into these, which are mutagenic.
Heterocyclic amines (HCAs)
Is there any evidence for a role of meat consumption in increasing cancer risk?
Yes, especially of colon, rectum, and prostate, although mechanism is unclear (could be unrelated factors like SES as well)
T/F: Incidence of stomach cancer in Japan is relatively low, while US rates are high and increasing.
False. • Incidence of stomach cancer in Japan is high while stomach cancer rates in US are low and declining (has decreased 4-fold since 1930).
• There is epidemiological evidence for a relationship between the intake of highly salted foods and stomach cancer
There appears to be a correlation between the decline in stomach cancer and decline in use of salt-pickling to preserve food.
What types of cancers is there an association between alcohol consumption?
Aerodigestive cancers: (oral cavity, pharynx, esophagus, larynx) & liver cancer
Weak association w breast ca, colorectal, and lung ca
What are phytochemicals and which ones are being tested as chemopreventive agents?
plant derived foods (veggies, fruits, whole grains) that contain 1000s of chemically diverse phytochemicals
• Carotenoids – carotene, lycopene, lutein
• Terpenes – perillyl alcohol
• Indoles – indole-3-carbinol
• Soy isoflavones – genestein, daidzein
• Polyphenols – curcumin
• Organosulphur compounds – diallyl sulphide
What is considered "obese" in men and women? How do you calculate a BMI?
• There is a statistical relationship between being overweight and decreased longevity.
• What is obesity? >/= 25% body fat in men, >/= 30% body fat in women
• Body Mass Index (BMI) Wt (kg)/ ht2 (m)
OR Wt in lbs x 0.454 / (ht in inches x 0.0253)^2
Values greater than 25-27 indicate increased health risk
Values of 30 or more are considered obese
Overestimates fatness in muscular or athletic people
Not a good index for adolescents or children
What are some diseases associated w obesity?
• cardiovascular disease - leading cause of death in US
• type II diabetes (maturity-onset)
• cholelithiasis (gall bladder disease)
• thrombosis (abnormal clotting & obstruction of blood supply)
While anemia may be the most common nutritional disorder, obesity is the most serious (in U.S.).
High serum cholesterol levels are clearly a risk factor in atherosclerosis. What values of TOTAL cholesterol are desirable, borderline, or high? LDL? HDL?
Less than 200 mg/dL ‘desirable' level that puts you at lower risk for heart disease. A cholesterol level of 200 mg/dL or greater increases your risk.
200 to 239 mg/dL ‘borderline-high.'
240 mg/dL and above ‘high' blood cholesterol. A person with this level has more than twice the risk of heart disease compared to someone whose cholesterol is below 200 mg/dL.
Recommended goal is 100 mg/dL (new recommendation 70 mg/dL ?)
Less than 40 mg/dL A major risk factor for heart disease
40 to 59 mg/dL The higher your HDL, the better
60 mg/dL and above is considered protective against heart disease.
What's the relationship between alcohol and heart disease?
Drinking too much alcohol can raise blood pressure, cause heart failure and lead to stroke. It can contribute to high triglycerides, cancer and other diseases.
The risk of heart disease in people who drink moderate amounts of alcohol (an average of one drink for women or two drinks for men per day) is 30-50% lower than in nondrinkers.
One drink is defined as 1-1/2 fluid ounces (fl oz) of 80-proof spirits (such as bourbon, Scotch, vodka, gin, etc.), 1 fl oz of 100-proof spirits, 4 fl oz of wine, or 12 fl oz of beer.
AHA does not recommended that nondrinkers start using alcohol or that drinkers increase the amount they drink.
What's the relationship between carbs, sucrose, and disease?
- some evidence that carb diets are associated w increased risk of CV disease --> CALORIES are MOST IMPORTANT
- sucrose is important factor in growth of plaque forming microorganisms (dietary sucrose is directly related to incidence of caries but NOT to periodontal disease)
- "Halloween effect" --> controlled experiments haven't been able to demonstrate a direct effect between dietary sucrose and hyperactivity in children
Are trans fats good or bad for you? What's their effect on LDL and HDL? What disease are they linked to?
Partially hydrogenated oils (trans fats or TFAs) are linked to coronary artery disease
they increase LDL cholesterol and decrease HDL cholesterol levels (markers for CAD)
Little is known about the mechanism of TFA action
What are some dietary supplements that may DECREASE the risk of heart disease?
Niacin: can decrease serum cholesterol and triglycerides, increase HDL and decrease LDL. Contra-indicated for ppl w abnormal liver fnctn or HBP. May experience skin flushing rxn
Omega-3 fatty acids: increase HDL cholesterol, decrease plasma triglycerides, reduce reactivity of platelets, monocytes, and neutrophils, reduce blood pressure, and have antiarrhythmic properties
Is there a direct relationship between dietary sodium and HTN?
Yes! •There is a direct relationship between sodium intake and blood pressure but it isn’t as clear how much salt is required to produce a clinically significant increase. This relationship is more acute in renal dialysis patients.
Human requirement is 4 gms NaCl/day
In Japan, daily intake is >400 meq/day and CV disease is 2nd most common cause of death
For whom is a low sodium diet risky?
• Individuals who do not produce enough ADH (adrenal insufficiency) should not be on low sodium diets.