Nutrition of development Flashcards
When is peak growth and requirements for nutrition per kilogram?
Infancy
(growth charts are best to measure growth and therefore assess nutrition)
What is “channel jumping”?
When a child skips rapidly between percentiles on their growth chart (e.g. born at 90th percentile and drops down to 5th)
What is rickets?
- A vitamin D deficiency in kids resulting in inadequate bone development
- widened growth plates/”cupping” observed on x ray
Describe the major functions of vitamin D in development
- primary function is to maintain calcium and phosphorus levels (promotes absorption in the GI tract
- supports bone calcification and neuromuscular function
What will the results of inadequate vitamin D be?
- lead to decreased calcium absorption
- prevent osteoblast action
- result in the failure of the bones to mineralize (**Rickets)
Describe the ways your body gets vitamin D
- oral intake
- absorption requires nromal fat metabolism (including pancreatic secretions, bile acid, adequate small intestine length, normal lymphatics)
- stored in the liver and activated in the kidney
- internal synthesis
- can be made from UV light by converting cholesterol form to a pre-vitamin D3
- high sun exposure does not guarantee adequate vitamin D
What are the fat soluble vitamins?
ADEK
What puts patients at risk for vitamin D deficiency?
- inadequate intake (e.g. picky eaters, solely breastfed infants, vegan diets)
- malabsorption (e.g. pancreatic insufficiency, CF, celiac)
- dark skin (melanin protects against UV rays; preventing vitamin D activation)
- inadequate sun exposure
What are the most common sources of vitamin D?
- dietary (most commonly animal forms)
- fatty fish (tuna, salmon, trout, mackerel)
- dairy products
- sun exposure
What are some functions of calcium throughout the body?
- primary function is to maintain bone structure
- also aids in…
- coagulation
- endocrine/exocrine function
- neuromuscular activity
- electrophysiology of heart and smooth muscle
**calcium absorption is highly dependent on vitamin D
Describe the sequence of events that elevates a low serum calcium
- low serum calcium activated parathyroid glands
-
PTH secreted which affects the intestines, bones and kidneys
- increased Ca absorption in the intestines
- osteoclasts activated in bone to release Ca
- Ca reabsorption increases in the kidneys
- all of these act together to increase serum Ca
What are some risk factors for calcium deficiency?
- preterm infants
- glucocorticoid therapy
- impairs bone mineralization
- decreases absorption and increases renal secretion
- inadequate intake
- lactose intolerance
- high fiber intake/low vitamin D intake
- malabsorption (fat malabsorption leads to calcium deficiency secondary to vit D deficiency)
- advanced age (less absorption)
What does albumin have to do with calcium levels?
- important in the calculation of corrected calcium
- corrected Ca= [0.8 x (4.0 - albumin)] + serum Ca
- low albumin levels may cause serum calcium levels to appear falsely low
What ages are the most important to have high calcium intake?
need ~1300 mg/day during pregnancy/lactation and in the teenage years (9-18 yo)
What are the best sources of dietary calcium?
- best= dairy (highest bioavailability)
- broccoli
- legumes
- oysters
**be sure to consume adequate vitamin D
What is the function of folic acid? When is deficiency a major issue?
- acts as a coenzyme in the metabolism of nucleic and amino acids by converting homocysteine to methionine
- B12 is essential part of this conversion
- deficiencies…
- during pregnancy causes congenital abnormalities due to altered metabolism (closure of the neural tube occurs 19-28 days after conception)
- in adulthood leads to macrocytic anemia
What patients are at risk for deficiency of folic acid?
- low intakes of fruits and vegetables in normal populations
- malnourished individuals
- under-supplementation during pregnancy
What are the best sources of dietary folic acid?
- fortified grains
- have decreased neural tube defects since fortification began in the late 90s!
- dark green vegetables
- beans/legumes
