Breastfeeding Lecture Notes PDF

BIOCHEM-LEC: LE 4 | TRANS 1 Breastfeeding KYLE S. GONZALES, M.D. | January 7, 2025 OUTLINE I. PHYSIOLOGY OF LACTATION I. Physiology of F....

BIOCHEM-LEC: LE 4 | TRANS 1 Breastfeeding KYLE S. GONZALES, M.D. | January 7, 2025 OUTLINE I. PHYSIOLOGY OF LACTATION I. Physiology of F. Goat’s Milk A. PLASMA HORMONE LEVELS DURING PREGNANCY Lactation Formula A. Plasma Hormone G. Hypoallergenic Levels During Formula Pregnancy H. Summary of B. Hormonal Control Modifications and of Lactation Enrichments of C. Let-Down Reflex Commercial Milk II. Breastfeeding Formulas III. Evaporated Milk VI. Advantages of A. Human Milk vs. Breastfeeding Evaporated Milk A. Short-term IV. Sweetened Benefits to the Condensed Milk Infant V. Humanized Milk B. Long-term Benefits A. Non-Premium to the Infant Formula C. Short-term B. Premium Formula Benefits to the C. High-Protein Mother Formula D. Long-term Benefits D. Premature to the Mother Formula E. Economic Benefits E. Soy Protein of Breastfeeding Figure 1. Plasma hormone levels during pregnancy[Lecturer’s PPT] Formula F. Societal Benefits of As pregnancy progresses, all plasma hormone levels Breastfeeding (progesterone, prolactin, and different forms of estrogen) VII. Summary increase. VIII. Review Questions IX. References B. HORMONAL CONTROL OF LACTATION X. Appendix SUMMARY OF ABBREVIATIONS Ig Immunoglobulin sIgA Secretory Immunoglobulin A NEC Necrotizing Enterocolitis PUFA Polyunsaturated Fatty Acid SFA Saturated Fatty Acid MCT Medium Chain Triglycerides ❗️ Must know 📣 Lecturer 📖 Book 📋 Previous Trans Figure 2. Hormonal control of lactation [Lecturer’s PPT] LEARNING OBJECTIVES ✔ Describe the physiology of lactation. STAGE OF DESCRIPTION ✔ Differentiate colostrum, transitional and human LACTATION mature milk. 1st part of pregnancy (Preparation) ✔ Compare the quantitative and qualitative properties of ALVEOLAR Estrogen & Progesterone breast milk and cow’s milk. PROLIFERATION stimulate breast tissues and ✔ Enumerate the advantages of breast milk over cow’s proliferate ducts and lobules milk. Occurs 12 weeks before parturition/ childbirth LACTOGENESIS Collection of substrates such as I immunoglobulins and proteins for lactation Starts postpartum Space intentionally left blank Removal of placenta results in LACTOGENESIS decreased levels of progesterone II and estrogen Colostrum is produced until transitional milk LE 4 TRANS 1 TG-C22: *S. Yambot, J. Yanzon, R. Yumang, G. Zacate, B. TE: S. Yambot, J. Zipagan AVPAA: E. See Page 1 of 10 Zafra, G. Zenarosa, J. Zipagan  LACTATION / Removal of initial milk (colostrum TYPE OF MILK (BASED ON TIMELINE) LACTOGENESIS and transitional milk) act as Colostrum 1st Sucking Day to 5th Day III stimulus for lactation Transitional Milk 4th to 10th Day of lactation No milk removal Human Mature Milk > 10th Day of lactation INVOLUTION Breast tissues revert back to natural and normal state TYPES OF MILK (GENERAL CHARACTERISTICS) Estrogen and Progesterone are INHIBITORY to lactation. Deep Yellow Thus, Milk is still NOT PRODUCED during pregnancy. Slightly Basic/Alkaline pH 7.7 Colostrum NO CORRELATION between prolactin levels and the Specific gravity 1.040 - 1.060 amount of breast milk produced. 10-40 mL/day Bluish and Watery C. LET-DOWN REFLEX Human Mature Neutral pH 6.8 - 7.4 (ave. 7) Milk Specific gravity 1.026 - 1.036 (ave. 1.031) *Less dense than conventional milk TYPE OF MILK (BASED ON HIGHEST NUTRIENT COMPOSITION) Proteins Colostrum Antibody (sIgA) (95% of proteins) (Anti-infective Vitamin A Properties) Minerals (Na+, K+) & Trace Elements (Fe) Macrophages (phagocytosis) Transitional Phosphorus Milk Fats Human Lactose Mature Milk Vitamin B Complex See Appendix for specific values of the succeeding tables below MATURE MILK VS. COW’S MILK 📋 Figure 3. Let-down reflex[Lecturer’s PPT] Table 1. Milk composition in human mature milk vs. cow’s milk AKA Milk ejection reflex NUTRIENT MATURE Stimulation = Nipple Suckling (there can be other stimuli) COW’S MILK COMPOSITION HUMAN MILK → Activation of Sensory Receptors → Afferent Nerve Water (ml) SAME Pathway → Hypothalamus → Pituitary Gland Energy (kcal/dl) INCREASED Hormone Source Function Protein (g/dl) INCREASED Anterior Pituitary Fat (g/dl) INCREASED Prolactin Milk Production Gland Lactose (g/dl) INCREASED Hypothalamus Ash (g/dl) INCREASED Milk Ejection Oxytocin (stored in Posterior Ash Content: The ash that remains after burning milk. (Myoepithelial Contracture) Pituitary Gland) Higher ash content means higher minerals in milk. Epinephrine and Norepinephrine has an INHIBITORY Table 2. Caloric distribution in human milk effect on milk ejection (Oxytocin) NUTRIENT % OF TOTAL CALORIES → No milk ejection = Involution Fats 1st (50%) II. BREAST MILK Carbohydrates 2nd (47%) Proteins 3rd (3%) LACTOSE Figure 6. Lactose[Lecturer’s PPT] Major and dominant human milk carbohydrate Figure 5. Human mature milk[Lecturer’s PPT] Why? Lactase is a major enzyme found in infants which allow lactose to be metabolized completely Disaccharide ▪ Glucose → energy ▪ Galactose & glucose → cerebrosides → CNS development BIOCHEMISTRY Breastfeeding Page 2 of 10  LACTOSE: ADVANTAGES PROTEINS FOUND IN MILK Facilitates intestinal absorption of Ca2+ and Mg2+ for Used to synthesize lactose and to Alpha-lactalbumin better bone mineralization absorb calcium and zinc Favors protein absorption for better protein utilization An iron binding protein and ensures Promotes growth of intestinal bacteria, which secretes Lactoferrin that iron in breast milk is better Vitamin K absorbed Promotes growth of microbial flora → ↓ pH → prevents Secreted by macrophages, aids in growth of pathogens Lysozymes killing microbes, cleaves bacterial Promotes predominance of fermentative stool flora cell wall Less sweet than sugar; therefore, less instances of IgA Main Antibody in Human Milk dental caries and decreases developing a sweet tooth in IgG and IgM Same content as serum children Responsible for most cow milk Beta-lactoglobulin OLIGOSACCHARIDES / COMPLEX CARBOHYDRATES allergies Other carbohydrates found in breast milk are Postulated Role: Non-protein Nitrogen is converted to nitrogen-containing complex carbohydrates such as: Essential Amino Acids during low protein, which serves as → N-acetylglucosamine a buffer. → Sialic acid—containing oligosaccharides and AMINO ACIDS polysaccharides Cow’s milk has HIGHER essential and non-essential These oligosaccharides constitute the bifidus factor amino acid content compared to Human Milk → These are the food for the good bacteria thus promoting See Appendix for the table with specific values (Tables 5 and 6) overgrowth of beneficial microbes such as the Bifidobacteria and Lactobacillus species FATS ▪ Crowds out harmful GIT pathogens (eg. E. coli) Major energy source ▪ Found in probiotic preparations – prevent NEC, Important for CNS myelinization treatment of colic and gastroenteritis in children Most variable component and is affected by: ▪ Lactobacillus shirota strain in Yakult and Chamyto → Maternal Diet PROTEINS Fish (Inuits, Japanese) High PUFA Table 3. Protein nitrogen fraction in human milk vs. cow’s milk Vegetable Oil High PUFA HUMAN MILK COW’S MILK CHO High SFA PROTEIN (g/dl) (increased glucose pathway of INCREASED Protein nitrogen milk lipid synthesis) a. Casein* INCREASED → Diurnal Variation b. Whey INCREASED ▪ Higher in early AMs The reason why proteins are low in human milk is because ▪ Higher at end of breastfeeding (hind milk) of the developing kidney of the baby. It has a lesser solute Order of Expression Fat Protein load compared to cow’s milk. Foremilk First Low High Whey is better than Casein because it is better absorbed Hindmilk Last High Low and digested by the baby. Casein forms precipitates which make it harder to digest Table 7. Fatty acid profile Table 4. Composition of protein nitrogen HUMAN COW’S CONTENT CONTENT HUMAN MILK COW’S MILK MILK MILK A. PROTEIN NITROGEN Total Fat INCREASED Whey INCREASED Unsaturated Fatty Acids INCREASED α-lactalbumin INCREASED Saturated Fatty Acids INCREASED Lactoferrin INCREASED Traces (Form precipitates with Lysozyme INCREASED Traces Ca+2) Serum albumin SAME Unclassified Fatty Acids INCREASED IgA (sIgA) INCREASED Essential Fatty Acids INCREASED IgG INCREASED Saturated fatty acids in human milk → medium chain fatty IgM SAME acids → Better Absorption β-lactoglobulin INCREASED MINERALS B. NON-PROTEIN Cow’s milk has a HIGHER content of minerals compared NITROGEN to human milk. Urea See Appendix for the table with specific values (Table 8) Creatine IRON INCREASED Creatinine Table 9. Iron Uric Acid CONTENT HUMAN MILK COW’S MILK Glucosamine Iron SAME α-amino Nitrogen 📋 % Absorption INCREASED IDA is uncommon in breast-fed infants due to HIGH lactoferrin content (Fe-binding protein that inhibits the growth of GIT and respiratory pathogens. BIOCHEMISTRY Breastfeeding Page 3 of 10  FAT-SOLUBLE VITAMINS V. HUMANIZED MILK Table 10. Fat-soluble vitamins Cow’s milk that tries to resemble human milk for infant CONTENT A (IU) HUMAN MILK COW’S MILK 📋 feeding Commercial milk formulas that are intended to effectively substitute breast milk but NOT as replacements D (IU) INCREASED E (IU) A. NON-PREMIUM FORMULA K (IU) DECREASED INCREASED Table 14. Composition of Human Milk vs. Non-premium Formula Lower Vitamin K in Human Milk → Routine Vitamin K Composition Non-premium Human Milk Administration in Newborn Infants (compensation) Factors formula Stable (Mature) Gut Microflora → Vitamin K Production Energy (kcal/dl) SLIGHTLY WATER-SOLUBLE VITAMINS INCREASED Table 11. H2O-soluble vitamins Protein (gm/dl) INCREASED CONTENT HUMAN MILK COW’S MILK Casein INCREASED Vit. C Whey INCREASED INCREASED Fat (gm/dl) INCREASED LOWER Vitamin B Complex (milk fat) (65-100% veg. oil) (Niacin, Thiamin, INCREASED Carbohydrate (lactose) INCREASED Riboflavin, B12, (gm/dl) (lactose & sucrose) Pyridoxine) No specific values given Minerals Slightly INCREASED Vitamins III. EVAPORATED MILK Fat-soluble Slightly INCREASED Cow’s milk evaporated at 55 – 60 °C → reduced to 50% of Water soluble Slightly INCREASED its volume Homogenized, sealed, autoclaved at 160 °C Non-premium formula is less expensive because of Pasteurization causes some damage to protein quality predominantly casein content B. PREMIUM FORMULA A. HUMAN MILK VS. EVAPORATED MILK Intended for healthy, uncompromised, and non-problematic Table 12. Composition of Human Milk vs. Evaporated Milk babies (from birth up to 6 months of age) Composition Human Evaporated Milk Relatively expensive Factors Milk Energy (kcal/dl) INCREASED Table 15. Composition of Human Milk vs. Premium Formula Protein (gm/dl) INCREASED Composition Human Milk Premium Formula (100% casein) Factors Fat (gm/dl) INCREASED Energy (kcal/dl) SLIGHTLY (coconut & corn oil) - INCREASED filled milk - inc. sat FA Protein (gm/dl) INCREASED Lactose (gm/dl) SAME Casein SAME Minerals Whey (WHEY > CASEIN) Calcium (mg/dl) Fat (gm/dl) INCREASED LOWER Phosphorus (mg/L) (milk fat) (100% veg. oil) Sodium (mg/L) Carbohydrate (lactose) INCREASED INCREASED (gm/dl) (lactose) Potassium (mg/L) Ash INCREASED Chloride (mg/L) Minerals INCREASED Iron (mg/L) Fat-soluble vitamins C. HIGH-PROTEIN FORMULA A E K (IU) SAME Other name: Follow-up formulas D (IU) INCREASED For babies 6 months and above H20-Soluble ↑ B1 B2 B6 Rapid body growth and development Vitamins ↓ Vit C Need for more proteins Relatively MORE expensive IV. SWEETENED CONDENSED MILK Table 16. Composition of Human Milk vs. High-Protein Formula Table 13. Composition of Human Milk vs. Condensed Milk Composition High-protein Composition Human Milk Human Milk Condensed Milk Factors formula Factors Energy (kcal/dl) SLIGHTLY Energy SLIGHTLY INCREASED (kcal/dl) INCREASED Protein (gm/dl) INCREASED Protein (gm/dl) INCREASED Casein SAME (casein predominant) Whey (WHEY > CASEIN) Fat (gm/dl) INCREASED (100% veg. oil) - inc. sat FA Fat (gm/dl) INCREASED LOWER (milk fat) (20-100% veg. oil) Carbohydrate (lactose) INCREASED (mostly (gm/dl) sucrose with lactose) Carbohydrate (lactose) INCREASED (gm/dl) (lactose, sucrose, Called “condensed milk” because it’s condensed with maltodextrin) sugar (lactose, sucrose). Ash INCREASED BIOCHEMISTRY Breastfeeding Page 4 of 10  Minerals INCREASED Soy protein formula has carnitine, which is linoleic Vitamins DECREASED acid-enriched Thiamine, → Carnitine: transports fatty acids from the cytosol to the Riboflavin, mitochondria for fatty acid oxidation. Pyridoxine → Linoleic Acid: long chain fatty acid responsible for CNS Development INCREASED F. GOAT’S MILK FORMULA Niacin Intended for those allergic to cow’s milk and/or soy Folic Acid products Vit. C ↓ Energy yield Vit B12 Lactose predominant Fat-soluble vitamins Whey predominant → ↓ B-lactoglobulin → less allergies D. PREMATURE FORMULA ↑ Ca+2, proteins & ash For low birth-weight infants Expensive For premature babies Currently not acceptable in many places because there To promote growth at intrauterine rates without disrupting are no robust randomized clinical trials metabolic processes G. HYPOALLERGENIC FORMULA Table 17. Composition of Human Milk vs. Premature Formula Intended for babies born to parents with strong family Composition history of allergy or those with allergy to proteins Human Milk Premature Formula Factors Homogenize proteins into smaller chunks for easier Energy (kcal/dl) INCREASED digestion thus reduces the risk of allergies in infants and Protein (gm/dl) INCREASED children Casein SAME Table 19. Composition of Human Milk vs. Hypoallergenic Formula Whey (WHEY > CASEIN) Composition Hypoallergenic Fat (gm/dl) INCREASED SLIGHTLY LOWER Human Milk Factors Formula (milk fat) (corn oil, coco oil, Energy (kcal/dl) SLIGHTLY MCT) INCREASED Carbohydrate INCREASED Protein (gm/dl) SLIGHTLY (gm/dl) (lactose, corn INCREASED syrup, maltodextrin) Casein SAME Minerals INCREASED Whey (WHEY > CASEIN) Vitamins INCREASED Fat (gm/dl) INCREASED LOWER (Vit. D) (milk fat) (veg. oil) Vegetable oil also has MCT, which is easily digested Carbohydrate (lactose) INCREASED compared to other saturated fats. (gm/dl) Carbohydrates consist of lactose, corn syrup and Minerals (gm/dl) INCREASED maltodextrin because it is high in energy. Premature infants don’t have enough lactase unlike term H. SUMMARY OF MODIFICATIONS AND babies. ENRICHMENTS OF COMMERCIAL MILK FORMULAS E. SOY PROTEIN FORMULA Table 20. Modifications and Enrichments of Commercial Milk Based on vegetable proteins (soya) Formulas Lactose free, “milk free” MODIFICATION/ COMMENTS For children with allergy to cow’s milk proteins or those ENRICHMENT with lactose or galactose intolerance Use of vegetable oil Increased level of saturated FA Table 18. Composition of Human Milk vs. Soy Protein Formula Addition of sucrose Nutritionally out of balance Composition Soy protein (in condensed milk) formula Human Milk Use of vegetable Lower biologic value Factors formula Energy (kcal/dl) SLIGHTLY protein (soya) INCREASED Lactose-free formula No benefits obtained from Protein (gm/dl) INCREASED (soy protein formulas) lactose (soy protein.) Addition of probiotics To support growth of healthy GIT Casein INCREASED and prebiotics flora (100%) Docosahexaenoic Adequate visual and brain Whey INCREASED acid/Arachidonic acid development → efficient brain (DHA/ARA) & taurin synapses Fat (gm/dl) INCREASED LOWER (milk fat) (24-100% veg. For brain growth and Addition of oil) development and strengthening nucleotides the baby’s immune system Carbohydrate (lactose) INCREASED (gm/dl) (sucrose, Essential Fats Essential for physical and mental maltodextrin) (Linolenic acid development [w-6]/Linoleic acid Carnitine + + [w-3]) Linoleic Acid + 250-500 Hypoallergenic Protein blend for those at risk of (mg/L) formulas developing allergy BIOCHEMISTRY Breastfeeding Page 5 of 10  Adequate development of visual A. SHORT TERM BENEFITS TO THE INFANT Use of MCTs, CHO and brain function; high energy Table 21. Short Term Benefits to the Infant blend of lactose, corn content for rapid growth in Neurobehavioral Benefits syrup & maltodextrin premature infants Reduce infant crying Increase blood glucose VI. ADVANTAGES OF BREASTFEEDING Early skin-to-skin contact levels Never be approximated between mothers and Promote greater A living biologic fluid newborns cardiorespiratory stability → Has antimicrobial fluid (IgA and IgG) in late preterm infants → Promote gastrointestinal growth, motility and function → Enhanced maternal-infant enhanced maturity of the GIT bonding Proteases Radiant warmth from the Has analgesic effect Hormones Cortisol, somatomedin-C, skin-to-skin contact. insulin-like growth factor (IGF), Higher salivary cortisol insulin and thyroid hormones levels in breastfed infants Growth Factors Epidermal Growth Factor (EGF), Gastrointestinal Functions Nerve Growth Factor (NGF), Reduce the risk of gastroenteritis and diarrheal disease Intestinal mediators (neurotensin, Increase the rate of gastric emptying motilin) Increase intestinal lactase activity in premature infants Enzymes Platelet-activating factor (PAF) Decrease the intestinal permeability early in life in acetylhydrolase premature infants Anti-Inflammatory Interleukin-10 Reduce the risk of developing NEC in preterm infants Agents Prevention of Acute Illnesses During Breastfeeding Free amino Acids Taurine, Glutamine Gastroenteritis and diarrhea Polyunsaturated Respiratory diseases Fatty Acids Coronavirus disease 2019 (COVID-19) (PUFA) Otitis media Contains the major nutrients (CHOs, fats & CHONs), Urinary tract infection vitamins & minerals in the right forms and proportions. Neonatal sepsis or infection in the newborn The composition of breast milk is NOT subject to human Sudden Infant Death Syndrome (SIDS) error Decreased risk of childhood mortality, lower rates of → Reason why breast milk is far superior to cow’s milk. hospitalizations and outpatient visits Contains living cells like white blood cells, macrophages RECAP: and lymphocytes that lower rates of the following: Anti-infective Properties → Gastroenteritis Colostrum sIgA, lactoferrin → Respiratory tract illnesses Mild laxative effect → Recurrent otitis media Antibodies to E. coli → Urinary tract infections Lysozyme → Sepsis in premature babies Anti-staphylococcal factor Lactoperoxidase Bile salt-stimulated lipase Productive lipid byproducts Free FAs & monoglycerides WBCs Neutrophils, lymphocytes Human milk (Glu, Gal, Glu-Nac, Fuc, oligosaccharides SA, & Lactose) B. LONG TERM BENEFITS TO THE INFANT Table 22. Long Term Benefits to the Infant Reduced risk of acute illnesses even after breastfeeding is discontinued Reduced risk of certain chronic illnesses related to Space intentionally left blank duration of breastfeeding: Moderate evidence of benefit Type I DM - longer breastfeeding is more protective Inflammatory bowel disease (IBD) (eg. Crohn's disease and ulcerative colitis) Wheezing - lower incidence in early childhood due to reduction in the number of upper respiratory infections Dental health Malocclusion Dental caries Reduced risk of certain chronic illnesses related to duration of breastfeeding: Limited evidence of benefit Leukemia and lymphoma BIOCHEMISTRY Breastfeeding Page 6 of 10  Allergic conditions like atopic asthma in older children VII. SUMMARY (after 6 years of age) or on eczema or allergic rhinitis (in Best for baby's and mother's health and well-being. all age groups) Reduces incidence of anemia, allergies and related Childhood obesity (appetite control mechanism) disorders. Type 2 DM Economical, no waste, no expense. Cardiovascular risk factors - like slightly lower blood Antibodies for greater immunity to infections. pressure (reduction of approximately 1 mm Hg) during Spacing of pregnancy due to lactation amenorrhea and childhood, which may not be clinically significant anovulation. Celiac disease Temperature is always correct and constant. Reduced risk of certain chronic illnesses related to Fresh milk never gets contaminated nor spoiled nor duration of breastfeeding: composition duplicated. Limited evidence of benefit Emotional development and maternal-infant bonding are Slightly improved performance heightened. Neurodevelopmental in intelligence tests; lower Excessive obesity, fatness and sweet tooth are avoided. outcomes severity and incidence of Digested and absorbed easily, and utilized efficiently. retinopathy of prematurity Immediately available, anywhere and anytime. Auditory-evoked responses Nutritionally balanced. Auditory function mature faster in breastfed Gastroenteritis, respiratory, urinary and other infections are premature infants greatly reduced. Attention Deficit Reduced incidence among VIII. REVIEW QUESTIONS Hyperactivity exclusively breastfed infants 1. Which hormone is primarily responsible for the milk Disorder (ADHD) ejection reflex during breastfeeding? Autism Spectrum Unclear association between a. Prolactin Disorder (ASD) breastfeeding and ASD b. Oxytocin Lower risk of behavior problems c. Progesterone in children at 5 yrs. of age and 2. What is the main carbohydrate in human breast milk? Child behavior breastfed for 4 months a. Sucrose compared with a shorter b. Maltose duration of breastfeeding c. Lactose Abuse and neglect: reduced odds in adolescents of 3. How does protein composition of human milk differ neglect and sexual abuse who were breastfed for 9 from that of cow’s milk? months or longer a. Human milk has more casein than whey. b. Cow’s milk has more whey than casein. c. Human milk has a higher proportion of whey than C. SHORT TERM BENEFITS TO THE MOTHER casein. Table 23. Short Term Benefits to the Mother 4. What is a key nutritional advantage of colostrum Contraceptive effect/"lactation amenorrhea" secondary compared to mature breast milk? to prolonged postpartum anovulation or delayed a. Higher fat content resumption of ovulation (spacing of pregnancy) b. Higher protein and immunoglobulin content Enhancement of uterine involution c. Higher lactose content Improved maternal response to stress 5. Which of the following benefits is associated with Insufficient evidence to determine the association of long-term breastfeeding for infants? breastfeeding with postpartum depression or weight a. Reduced risk of type 1 diabetes change b. Reduced risk of type 2 diabetes c. Increased risk of obesity D. LONG TERM BENEFITS TO THE MOTHER Table 24. LongTerm Benefits to the Mother ANSWER KEY Decreased incidence of breast, epithelial ovarian and 1. B. Oxytocin is released from the Hypothalamus in endometrial CA response to suckling and stimulates contraction Modest reduction in CVD (e.g. hypertension) but may of the myoepithelial cells of the mammary wane as a woman ages glands, leading to milk ejection. Prolactin is Reduced risk for Type 2 DM during the yrs. after delivery responsible for milk production, not ejection. Remains uncertain in reduction of risk for osteoporosis 2. C. Lactose is the dominant carbohydrate in human E. ECONOMIC BENEFITS OF BREASTFEEDING milk. It is important for energy and helps in Table 25. Economic Benefits of Breastfeeding calcium and magnesium absorption, promoting Breastfeeding is inexpensive better mineralization. No need for vitamins 3. C. Human milk is predominantly whey (60%) Costs nothing for food compared to casein (40%), which makes it easier to digest for infants. Cow’s milk has a Fewer medical bills higher casein content, which can be harder for Decrease in parental work absences babies to digest. F. SOCIETAL BENEFITS OF BREASTFEEDING 4. B. Colostrum is rich in proteins, particularly Table 26. Societal Benefits of Breastfeeding immunoglobulins like sIgA, which provide Reduced infant mortality immune protection. It also has lower fat and Reduced incidence of chronic childhood diseases lactose compared to mature milk. Lower carbon footprint BIOCHEMISTRY Breastfeeding Page 7 of 10  5. A. Long-term breastfeeding has been shown to Escamilla-Perez R, Segura-Perez, Maternal and economic reduce the risk of type 1 diabetes and other benefits of breastfeeding, UpToDate, Apr 22, 2024. chronic illnesses. It also supports better Lawrence, R. Breastfeeding, A guide for the medical profession. 9th Ed. Elsevier 2022. neurodevelopmental outcomes and reduced Martin CR, Ling PR, Blackburn GL, Review of infant feeding: key risk of obesity. features of breast milk and infant formula. Nutrients. 2016 May 11; 8 (5): 279. Doi: 10.3390/nu8050279. PMID: 27187450. IX. REFERENCES Spencer J. Common problems of breastfeeding and weaning. Academy of Breastfeeding Medicine, ABM Clinical Protocol #9: UpToDate. May 27, 2024. use of galactogogues in initiating or augmenting maternal milk production, Second Revision, 2018 BIOCHEMISTRY Breastfeeding Page 8 of 10  X. APPENDIX Table 1. Milk composition in human mature milk vs. cow’s milk Table 7. Fatty acid profile NUTRIENT MATURE COW’S MILK HUMAN COW’S COMPOSITION HUMAN MILK CONTENT MILK MILK Water (ml) 87.1 87.2 Total Fat 4.5 3.7 Energy (kcal/dl) 69.0 66.0 Unsaturated Fatty Acids 48 33 Protein (g/dl) 1.1 3.5 Saturated Fatty Acids* 49 67 Fat (g/dl) 4.5 3.7 Unclassified Fatty Acids 3 Lactose (g/dl) 6.8 4.9 Essential Fatty Acids 7 3 Ash (g/dl) 0.2 0.7 *Form precipitates with Ca+2 Table 3. Protein nitrogen fraction in human milk vs. cow’s milk Table 8. Minerals HUMAN MILK COW’S MILK HUMAN PROTEIN (g/dl) 1.1 3.5 CONTENT COW’S MILK MILK Protein nitrogen 1.43 5.03 Calcium (mg/100 ml) 340 1170 a. Casein* 40% 82% Phosphorus (mg/100 ml) 140 920 b. Whey 60% 18% Sodium (mEq/L) 7 22 Potassium (mEq/L) 13 35 Table 4. Composition of protein nitrogen Chloride (mEq/L) 11 29 HUMAN COW’S CONTENT MILK MILK Table 9. Iron A. PROTEIN NITROGEN CONTENT HUMAN MILK COW’S MILK Whey INCREASED Iron 0.50 0.50 α-lactalbumin 0.42 0.17 % Absorption 45 10 Lactoferrin 0.27 traces β-lactoglobulin - 0.57 Table 10. Fat-soluble vitamins Lysozyme 0.08 traces CONTENT HUMAN MILK COW’S MILK Serum albumin 0.08 0.07 A (IU) 1898 1025 IgA (sIgA) 0.16 0.005 D (IU) 22 14 IgG 0.005 0.096 E (IU) 2 0.4 IgM 0.003 0.005 K (IU) 15 60 B. NON-PROTEIN 0.50 0.28 NITROGEN Table 12. Composition of Human Milk vs. Evaporated Milk Urea 0.25 0.13 Composition Creatine 0.37 0.009 Human Milk Evaporated Milk Factors Creatinine 0.035 0.003 Energy (kcal/dl) 69 152 Uric Acid 0.005 0.008 Protein (gm/dl) 1.1 7.8 Glucosamine 0.047 - (100% casein) α-amino Nitrogen 0.002 0.006 Fat (gm/dl) 4.3 6.5 (coconut & corn oil) - filled Table 5. Essential amino acids (mg/100 mL) milk - inc. sat FA CONTENT HUMAN MILK COW’S MILK Lactose (gm/dl) 6.8 6.8 Histidine 22 95 Calcium (mg/dl) 340 2750 Isoleucine 68 228 Phosphorus 140 2112 Leucine 100 350 (mg/L) Lysine 73 277 Sodium (mg/L) 7 55 Methionine 25 88 Potassium 13 77 Phenylalanine 48 172 (mg/L) Threonine 50 164 Chloride (mg/L) 11 46 Tryptophan 18 49 Iron (mg/L) 0.5 2.43 *L-isomers Fat-soluble vitamins Table 6. Non-essential amino acids (mg/100mL) A E K (IU) Same same CONTENT HUMAN MILK COW’S MILK D (IU) 22 420 Arginine 45 129 H20-Soluble ↑B1 B2 B6 Alanine 35 75 Vitamins ↓Vit C Cysteine 22 32 Glutamate 320 680 Glycine 0 11 Proline 80 250 Serine 69 160 Tyrosine 61 179 BIOCHEMISTRY Breastfeeding Page 9 of 10  Table 13. Composition of Human Milk vs. Condensed Milk Table 17. Composition of Human Milk vs. Premature Formula Composition Composition Premature Human Milk Condensed Milk Human Milk Factors Factors Formula Energy (kcal/dl) 69 67 Energy (kcal/dl) 69 81 Protein (gm/dl) 1.1 1.6 Protein (gm/dl) 1.1 1.9-2.2 (casein Casein 40% 40% predominant) Whey 60% 60% Fat (gm/dl) 4.3 1.6 (100% veg. Fat (gm/dl) 4.5 (milk fat) 4.32-4.4 (corn oil, oil) - inc. sat FA coco oil, MCT) Carbohydrate 6.8 - lactose 11.7 lactose Carbohydrate 6.8 (lactose) 8.0-8.6 (lactose, (gm/dl) 43.7 sucrose (gm/dl) corn syrup, maltodextrin) Table 14. Composition of Human Milk vs. Non-premium Formula Minerals slightly ↑ Composition Non-premium Vitamins ↑ esp. Vit. D Human Milk Factors formula Energy (kcal/dl) 69 67 Table 18. Composition of Human Milk vs. Soy Protein Formula Protein (gm/dl) 1.1 1.5-1.7 Composition Soy protein Casein 40% 60-70% Human Milk Factors formula Whey 60% 30-40% Energy (kcal/dl) 69 67 Fat (gm/dl) 4.5 (milk fat) 3.2-3.5 (65-100% Protein (gm/dl) 1.1 1.9-2.1 (soy prot.) veg. oil) Casein 40% 100% Carbohydrate 6.8 (lactose) 7.1-7.4 (lactose & Whey 60% (gm/dl) sucrose) Fat (gm/dl) 4.5 (milk fat) 3.3-3.5 (24-100% Minerals slightly ↑ veg. oil) Vitamins Carbohydrate 6.8 (lactose) 6.9-7.4 (sucrose, Fat-soluble slightly ↑ (gm/dl) maltodextrin) Water soluble slightly ↑ Carnitine + + Linoleic Acid + 250-500 Table 15. Composition of Human Milk vs. Premium Formula (mg/L) Composition Premium Human Milk Table 19. Composition of Human Milk vs. Hypoallergenic Formula Factors Formula Energy (kcal/dl) 69 67-68 Composition Hypoallergenic Human Milk Protein (gm/dl) 1.1 1.5 Factors Formula Casein 40% 40% Energy (kcal/dl) 69 67 Whey 60% 60% Protein (gm/dl) 1.1 1.13 Fat (gm/dl) 4.5 (milk fat) 3.4-3.7 (100% Casein 40% 40% veg. oil) Whey 60% 60% Carbohydrate 6.8 (lactose) 7.-7.2 (lactose) Fat (gm/dl) 4.5 (milk fat) 3.21 (veg. oil) (gm/dl) Carbohydrate 6.8 (lactose) 7.74 Ash 0.2 0.4-2.5 (gm/dl) Minerals slightly ↑ Minerals (gm/dl) 0.2 0.31 Table 16. Composition of Human Milk vs. High-Protein Formula Composition High-protein Human Milk Factors formula Energy (kcal/dl) 69 67 Protein (gm/dl) 1.1 2.9-3.1 Casein 40% 40% Whey 60% 60% Fat (gm/dl) 4.5 (milk fat) 2.6-2.75 (100% veg. oil) Carbohydrate 6.8 (lactose) 7.4-8 (lactose, (gm/dl) sucrose, maltodextrin) Ash 0.2 0.5-0.6 Minerals slightly ↑ Vitamins ↓Thiamine,Riboflavin , Pyridoxine ↑Niacin, Folic Acid, Vit. C, Vit B12, and Fat-soluble vits. BIOCHEMISTRY Breastfeeding Page 10 of 10