Nutrition Through the Life Cycle - Lactation Flashcards
When does mammary tissue in the breast begin growing?
Onset of puberty
When does breast tissue, mammary glands and ducts develop?
During adolecence
What trimester in pregnanacy does the breast tissue change so milk can be produced?
3rd trimester
In order from outside in, what is the anatomy of the breast?
Nipple > areola > lactiferous sinus > milk production and storage cells > fat tissue > muscle
How many lactiferous ducts are present in each nreast?
15-20 lobes per breast
What is the purpose of lactiferous sinuses?
Limited milk storage between feeds
What cells are responsible for milk synthesis?
Alveolar cells (drain into lactiferous duct)
What triggers the production of milk?
The birth of the baby
What is colostrum? What is its purpose?
An immature milk produced in the first 2-3 days postpartum. Thick, sticky, yellow fluid produced in 100mL/day quantities.
Purpose:
- Protective. Promotes maturation of the gut
- Low fat/lactose content
- High protein content (immunoglobulins, lactoferrin and vitamin A)
What is transitional breast milk?
Produced between 3-7 days postpartum and produced in larger volumes than colostrum.
Lower protein content than colostrum.
Lactose and fat content similar to mature milk.
When is mature breast milk produced?
From 14 days postpartum
What patterns are seen in the macronutrient composition of colustrum > transitional > mature breastmilk?
Energy, fat and carbohydrate content increase from colostrum > mature milk
Protein content decreases from colostrum > mature milk
What patterns are seen in the micronutrient composition of colustrum > transitional > mature breastmilk?
Sodium, vitamin A and vitamin C all decrease from colostrum > mature milk.
Folate increased from colostrum > mature milk.
At the peak of lactation, how much milk is produced a day? What is the primary energy form in mature breastmilk?
750-850mL/day.
Fat as triglycerols (50%)
CHO as lactose (40%)
Protein as whey protein (α-lactalbumin & lactoferrin)
What is the difference between foremilk and hindlmilk?
Foremilk:
- First milk to be released during a feed
- More watery than hindmilk
- Lower fat content and richer in lactose
Hindmilk:
- Released on full milk letdown
- More nutrient and energy dense
- Thicker than foremilk
Does the composition of breastmilk change throughout the day?
Yes
The primary carbohydrate content of milk comprimises lactose (80%). What are the remaining carbohydrates and what are their purpose?
Oligosaccharides.
Act as prebiotics for the infant.
The primary fat content of milk comprimises triglycerides (98%). What are the remaining fats?
Diglycerides, monoglycerides, free FAs, cholesterol and phospholipids
What are the major proteins found in breastmilk?
α-lactalbumin & lactoferrin
What 2 hormones are produced during milk secretion and milk ? Where are these hormones produced from?
prolactin (milk secretion) - anterior pituitary gland
oxytocin (milk ejection) - posterior pituitary gland
What should the general weightloss be per month for a woman?
0.8kg lost/month
Roughly how many kcal/day are expended due to breastfeeding?
650kcal/day
What is the energy content of milk (per g)?
0.67 kcal/g
What are the additional energy requirements (kcal/day) required by a breastfeeding woman? How long for?
additional 330 kcal/day approx. for first 6 months.
What are the additional requirements/day for breastfeeding women:
Calcium?
Vit A?
Calcium: +550mg/day
Vit A: +350ug/day
*SACN
What are some advantages of breastfeeding for the mother?
- Long-term health benefits for infant
- Cost-free
- Emotional bond
- Oxytocin releases eases anxiety
- Delayed reproductive cycling
- Faster return to prepregnancy weight
- Decreased cancer risk
- Bone mineral density loss slower (increased Ca bioavailability)
What is the % decrease of cancer from each birth?
7% each birth
Extra 5% if breastfeeding
How long until bone mineral density has returned back to normal for a breastfeeding mother?
12-18 months after weaning
What are some advantages of breastfeeding for the infant?
- Main nutrient source
- Provides optimal nutrients even if maternal diet is inadequate
- Provides immunoreceptors
- Brain/mental health from DHA
- Lower resiratory tract infections
- Lower risk for diabetes
Studies have shown a what % decrease in obesity risk for those who were breastfed?
22% decrease for obesity than bottle-fed infants
What signs might suggest the infant is getting enough milk/day?
- urination 6-8 times a day
- adequate weight gain
- good skin tone
- 3-4 stools a day
Within how long should the infant be fed colostrum after birth?
Within the first hour
For how long should breastfeeding continue?
exclusively for 6 months. Up to 2 years
The UK has one of the lowest breastfeeding rates in Europe. What % of babies are breasfed in the UK?
34%
Benefits and disadvantages of infant formulas as breastfeeding alternative?
Benefits:
Convenient
Dis:
- Ensuring correct quantities
- Expensive
- No breastfeeding bond
- No hormone release (increased cancer risk)
- May not contain required nutrients
- Nutritionally less adequate (vegetable oils as fat replacement)
How long should a mother wait until breastfeeding after 1 drink of alcohol?
What are disadvantages of alcohol consumption when breastfeeding?
2-3 hours
Dis:
- Changes breasmilk taste and odour
- Infant drinks less
- Infant sleeps less after consumption
- Infant lower psychomotor development
How long should a mother wait until breastfeeding after smoking?
What are disadvantages of smoking when breastfeeding?
At least 3 hours
Dis:
- Reduce milk volume
- Second hand smoke
- Nicotine levels in breastmilk are up to 3x higher than in blood
What % of caffeine does the infant consume from the mother?
What are disadvantages of caffeine when breastfeeding?
1% from mother
Dis:
- Hyperactive, fussy infant
- Caffeine accumulates in infants <3-4months as they cannot metabolise it
