Physiology of Lactation

Lactation: production of milk by mammary gland : increase size of the breast, areola and nipple

Colustrum: First milk : milk production controlled by oxytoxin and prolactin : Acts as a laxative that initially cleans the digestive system : 2nd to 5th day after delivery

Nutritional requirement during Lactation:

Energy: 500 kcal added : 100 cc of milk requires about 85 kcal

water and other fluid: liberal water intake or 3 quarts a day: inadequate fluid reduce milk production

Protein: additional 16gm/day for 6 months and 12 gms/day for the 2nd 6 months:1.2 gms of protein is stored in 100 ml of human milk: second six months milk secretion decreases to 500 ml/day

Lipid: human milk has about 10-20 mg/ml of cholesterol Minerals= calcium: plus 400 mg / day

iodine: additional 50 mcg/dayVitamin A: increased by 325 mcg by 1st 6 months

: Increased by 275 mcg by 2nd 6 monthsFolic acid : plus 100 mcg/ day for lactationB6 increase

Advantages:1. Nutritional superior2. Bacteriological safe3. fresh and right temperature for the body 4. contains immune cells and antibodies 5. least allergenic 6. closer mother baby ties 7. convenient8. least allergenic6. closer mother baby ties 7. convenient 8. least likely to be overfed 9. promotes good tooth and jaw development

Breast feeding problems: allow BF with: DM , multiple sclerosis, systemic lupus, HPN, Hep. C without con-infection, chrohn’s disease, ulcerative colitis, hyperlipoproteinemia, cystic fibrosis, kidney transplant, benign breast cyst, galactosemia, phenylketonuria.BF Contraindicated to: breast cancer detected during pregnancy , HIV , Active tuberculosis.

Nutrition in Pregnancy

First year of life characterized by rapid physical growth and developmentwt. doubles by 4-6 months and triples by the end of 1st yearLength increase to 50% by the end of first year and double at the age of 4The stomach capacity of infants increases from 20-30 ml to 200 ml at the age of 1 year

Nutrient allowances

Factors that determine individual needs for nutrients includes: age, gender, body size , rate of growth and physical activityEnergy: from metabolism of fat, carbohydrates and protein

: energy requirement is very high per unit of body size in the first few months of life but declines as rate of growth decreases

: Higher basal metabolic demands is due to larger loss of heat because of greater body surface and larger proportion of metabolic tissue

: best evaluation of the sufficiency of the infant or child energy intake is adequacy of their growth rates in length and weightProtein: for synthesis of new tissues and nitrogen for the maturation on existing tissues

: 3.5 gm/day for first 4 months and 3.1 gm/day for the next 8 months : body protein increase from 11% to 14.6% in the first year : human milk or formula provides the major protein source during infancy: inadequate protein intake due to: poverty, excessive dilution of formula,

continuation of regimen designed to treat diarrhea after an enteric illness, multiple food allergies or extreme vegetarian food patterns

: peanut butter and whole wheat bread, sandwiches beans and rice, eggs and powdered milk are in inexpensive high quality protein sources.Fat/lipids: supplies 40-50% of energy during infancy

: provide by human milk, cow’s milk and formula (50%) : can lead to obesity

: linoliec is essential for growth and dermal health and should provide 4-5 percent of total Kcal

Human milk: 4% of linoleicInfants formula: 10% of linoleic Cow’s milk: 1% of linoleic

Carbohydrates should supply to 60% of the energy intake during the infancy: 37% in human milk and 40- 50% of energy from commercial formulas is derived from lactose and other carbohydrates Water: transport nutrients and helps to regulate body temperature• water requirement of an infants is deternmined by the amount of lost from the skin, lungs, urine and feces.• 1.5 ml/kcal/day• Infants are vulnerable to water imbalance due to insensible water loss and renal concentrating ability is less

• in hot environment infants needs more water • monitor for diarrhea and vomiting • water intoxication

Age Water requirement (ml/kg/day)10 days 125-1503 months 140-1506 months 130-1551 year 120-1352 years 115-1256 years 90-10010 years 70-85

Vitamins: milk from lactating mothers supply all the vitamin than that full term baby needs Vit. D• Humans milk contains only 40-50 lu/ l so breastfed infants need a Vit. D supplements or be exposed to sunlight for at least 30 minutes per week for those wearing only diaper or 2 hours/ week for those fully clothe without hat• evaporized and homogeniezed cow’s milk contains little Vit. C• fresh goat’s milk is deficient in Vit. C, D and folate• vegetarian mothers may have vit. B12 deficient milk• hemorrhagic disease of the newborn is more common among breastfeed infants because human milk contains only 15 ug/L of vit. K

Minerals:Calcium: during the first 2-3 days of life, the level of plasma calcium and phosphorus fall significantly• Calcium level stabilize at 10th day • serum calcium concentrations I infants on breastmilk are grater than formula fed infant • formula fed infant retains 25-30% of calcium in cow’s milk. Breastfed infants ingests less calcium but retain approximately 2/3 of intake (240 from 750 ml of milk)• Iron; signs of anemia appears after 12 months age• recommended 6 mg/day during the first 6 months to 10 mg/day until 3 years of age• breastfed infants are at risk fro negative iron balance starting at 4-6 months and may deplete their reserves by 6-9 months• Formula fed and breastfed infants should receive supplement such as iron fortified cereals by 4-6 months of ageZinc= normal infants do not have zinc reserves • human milk and infant formulas provide adequate zinc, o.3 –o.5 mg/kg body weight during the first year of life.Fluoride: 4- 1000 mg/day can cause fluorosis

: breastmilk has a very low fluoride content• powdered formula have increase concentrations than concentrated formula• powdered formula have higher concentrations than concentrated formula• commercially prepared infants cereals, wet pack cereals and fruit juice produced from fluoridated water are good sources of fluoride

• after tooth eruption fluoridated water can be offered

Nutritional assessmentAnthropometry; assess physical size and growth by wt., length and head circumference

• wt. should be measured to nearest 10g for infants • length is measured in the recumbent position on a measuring board that has a fixed head board.

• Head circumference confirms that the growth is proceeding normally

Biochemical assessment ; iron status using hemoglobin or hematocrit determination

Dietary assessment: provide information in the adequacy of an infants diet and can be used to develop plans for resolving concerns or problem about food and nutrient patterns - interview is the most important aspect of any of the tools used

Clinical examination: feeding the normal full term infant:Breastfed infant1. Its composition is designed to provide the necessary energy and nutrient in appropriate amounts - Cow’s milk is not recommended for infant feeding until 1 year of age.

Breast Milk Cow’s Milk20 kcal/oz 20 kcal/oz

Protein 6-7% of energy 20% of energy 60% whey 20% whey40% casein 80% casein

Lipids 50% of energy 50% of energy

Casein forms a tough, hard to digest curd in the infants stomachTaurine and cysteine: essential for premature infants : increase in human milk rather than cow’s milk Lactose provide 42% of energy in breastmilk and only 30% in cow’s milkLipids: provide 50% of the energy and cow’s milkArachidonic acid and docosahexaenoic acid: found in breastmilk but not in cow’s milk Human milk contains 7- 47 mg/dl of cholesterol compared to 10-35 mg/dl in cow’s milk Human and cows milk have small iron content (0.3 mg/L)Cow’s milk contains 3 times as much as calcium, 6 times as much as phosphorus and twice as much fluoride as human milk increasing the renal solute load.Sodium and potassium in human milk is 1/3 of cow’s milk reducing the renal solute load2. It contain factors that provide protection against certain bacteriologic infections, diarrhea and otitis media.3. Allergic reactions to human milk are relatively rare

4. The closeness between the mother and the infant during breastfeeding facilitates attachment and bonding.

Formula milk:Soy based formulas are available for infants that do not tolerate cow’s milk indicating of soy based formulas:1. children of vegetarian families2. Children with galactosemia and primary lactose deficiency3. allergic to cow’s milk

Mutramigen or progestimil; milk of infant itolerant of milk productsunmodified cow’s milk : not recommended during infancy because its tough, hard curd is difficult for the infants to digest and lesser fat is absorbcontains higher protein

Nutrition problem during infancyobesity: wt. above 95 percentilebaby bottle tooth decaycolic: severe abdominal pain in infants- s/s cry for several hours, draw their legs into their abdomen and pass large amount of gas-can be cause by food allergy- ttt: hypoallergenic formula, instruct mother to eliminate milk, onions , and chocolate in her diet

LBWDefinition:term infant: born between the 37 and 42 week of gestationpreterm or premature infants: born before the 37th week of gestation post term infant: born after 42nd week of gestationLBW: infant who weigh less than 2500gVery LBW: weighs less than 1500 gExtremely low birth weight infant: birthweight less than 1000g SGA: birth weight less than 10th percentileAGA: birth weight between 10th -90th percentileLGA: birth weight above 90th percentile.