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sn-2 palmitate & a2 beta-casein

Date: Tuesday, May 18, 2021

No one knows a child better than his or her mother. Some people call it “mother’s instinct” and reflects the expertise a mother gains from spending lots of time with her child, learning their verbal and nonverbal cues, and blending knowledge with experience to respond intuitively.

Mothers go to great lengths to ensure their babies grow and develop well by nourishing them with quality nutrition, taking cues from their baby’s poo – appearance and frequency – and ensuring their babies get enough restful sleep.

Every milestone – every centimetre of growth – is noted and celebrated. Every morsel of food offered is carefully selected and lovingly prepared.

Wyeth® Nutrition keeps at the forefront of nutritional science to identify new ways to support mothers in meeting the nutritional needs of their growing children.

sn-2 palmitate and A2 beta-casein are two specific components that have been identified to be responsible for the goodness in milk. sn-2 palmitate provides multiple benefits on the health and well-being of children, and A2 beta-casein has been shown to support digestive comfort.


What is sn-2 palmitate?

Majority of the fats found in milk are in the form of triglycerides: three fatty acids are bound at the sn-1, sn-2 and sn-3 positions. Palmitic acid is one of the most common fatty acid found in milk.

Palmitic acid in a triglyceride molecule

Palmitic acids in human milk are typically bound at the sn-2 position, also known as the ‘beta’ position. Palmitic acids in this position are thus called sn-2 palmitate or beta-palmitate.


During digestion, sn-2 palmitate is readily absorbed and does not form insoluble calcium soaps in the intestine.1

Absorption process in the intestines


Palmitic acids positioned at sn-2 are less likely to bind with calcium to form insoluble calcium soap. This enables the body to better absorb key nutrients, like calcium and fats.


Palmitic acids positioned at sn-1 and sn-3 position are more likely to bind with calcium, forming insoluble calcium soaps which are generally associated with hard stools.


In the manufacture of formula milk, advanced technology makes it now possible to use oil blends that are rich in sn-2 palmitate. This ensures that the formula milk meets not just the desired quantity, but also the quality, of palmitic acid.

Formula milk with high levels of sn-2 palmitate can provide multiple benefits to a growing child. Studies have shown that:

sn-2 Palmitate Helps to:


Nutrient Absorption4


Strong Bones11


Restful Sleep9,10


Happy Tummy7,8


Soft Stools7,8

  • Children fed with formula milk with high sn-2 palmitate had less insoluble fatty acid soaps and calcium in their stools than those who received standard formula, suggesting that sn-2 palmitate enable better absorption of these nutrients.2-6
  • Formula milk with high sn-2 palmitate promotes the growth of a healthy gut microbiota, which not only helps with food digestion and absorption of nutrients, but in strengthening a child’s immune system.7,8
  • As sn-2 palmitate is readily absorbed and does not form insoluble calcium soaps, it helps reduce the formation of hard stools4,7
  • Reduced crying and improved sleep duration were observed among children who consumed sn-2 palmitate-enriched formula milk compared with those who received standard formula.9,10
  • Consumption of formula milk with higher sn-2 palmitate has led to significantly higher measures of bone strength in children, compared with those who consume standard formula.4,11,12


What is A2 beta-casein?

Casein is a type of protein found in milk and is classified into different groups: alpha-casein, beta-casein and kappa-casein. Beta-casein is further classified as A1 or A2 beta-casein types. In breast milk, the beta casein is of the A2 type.

A2 beta-casein is the original variant found in cow’s milk. However, over 5,000 years ago, a gene mutation occurred, resulting in cows that produce A1 ß-casein as well.

Recent research shows that only 30% of cows today are pure A2 cows,13 producing milk that contains only A2 beta-casein.


Originally, cows produced milk that had A2 ß-casein.

However, over 5,000 years ago, a gene mutation occurred, resulting in cows that produce A1 ß-casein as well.

Recent research shows that only 30%13 of cows today are pure A2 cows, producing milk that contains only A2 ß-casein.

The difference between the A1 and A2 types of beta-casein lies in their protein structure. Digestion of A1 beta-casein releases smaller protein fragments which can cause digestive discomfort, such as flatulence and gassiness. In contrast, A2 beta-casein is broken down differently and does not result in these symptoms.14,15

These findings suggest that formula milk made strictly with milk from A2 cows may help reduce symptoms of gut discomfort, so the body can absorb the nutrients it needs, without having a fussy tummy.

A2 ß-casein Helps to Support Gastrointestinal Well-Being


Reduce flatulence14


Reduce gastrointestinal discomfort15


  • 1. Mu H, Høy CE. The digestion of dietary triacylglycerols. Prog Lipid Res. 2004;43(2):105–133.
  • 2. Carnielli VP, Luijendijk IH, van Goudoever JB, et al. Feeding premature newborn infants palmitic acid in amounts and stereoisomeric position similar to that of human milk: effects on fat and mineral balance. Am J Clin Nutr. 1995;61(5):1037–1042.
  • 3. Carnielli VP, Luijendijk IH, Van Goudoever JB, et al. Structural position and amount of palmitic acid in infant formulas: effects on fat, fatty acid, and mineral balance. J Pediatr Gastroenterol Nutr. 1996;23(5):553–560.
  • 4. Kennedy K, Fewtrell MS, Morley R, et al. Double-blind, randomized trial of a synthetic triacylglycerol in formula-fed term infants: effects on stool biochemistry, stool characteristics, and bone mineralization. Am J Clin Nutr. 1999;70(5):920–927.
  • 5. López-López A, Castellote-Bargalló AI, Campoy-Folgoso C, et al. The influence of dietary palmitic acid triacylglyceride position on the fatty acid, calcium and magnesium contents of at term newborn faeces. Early Hum Dev. 2001;65 Suppl:S83–S94.
  • 6. Bar-Yoseph F, Lifshitz Y, Cohen T, Malard P, Xu C. SN2-Palmitate Reduces Fatty Acid Excretion in Chinese Formula-fed Infants. J Pediatr Gastroenterol Nutr. 2016;62(2):341–347.
  • 7. Yao M, Lien EL, Capeding MR, et al. Effects of term infant formulas containing high sn-2 palmitate with and without oligofructose on stool composition, stool characteristics, and bifidogenicity. J Pediatr Gastroenterol Nutr. 2014;59(4):440–448.
  • 8. Yaron S, Shachar D, Abramas L, et al. Effect of high β-palmitate content in infant formula on the intestinal microbiota of term infants. J Pediatr Gastroenterol Nutr. 2013;56(4):376–381.
  • 9. Litmanovitz I, Bar-Yoseph F, Lifshitz Y, et al. Reduced crying in term infants fed high beta-palmitate formula: a double-blind randomized clinical trial. BMC Pediatr. 2014;14:152.
  • 10. Bar-Yoseph F, Lifshitz Y, Cohen T, Malard P, Li Z, et al. SN2-palmitate improves crying and sleep in infants fed formula with prebiotics: A double-blind randomized clinical trial. Clinics Mother Child Health. 2017;14:263.
  • 11. Litmanovitz I, Davidson K, Eliakim A, et al. High Beta-palmitate formula and bone strength in term infants: a randomized, double-blind, controlled trial. Calcif Tissue Int. 2013;92(1):35–41.
  • 12. Béghin L, Marchandise X, Lien E, et al. Growth, stool consistency and bone mineral content in healthy term infants fed sn-2-palmitate-enriched starter infant formula: A randomized, double-blind, multicentre clinical trial. Clin Nutr. 2019;38(3):1023–1030.
  • 13. Massella E, Piva S, Giacometti F, Liuzzo G, Zambrini AV, Serraino A. Evaluation of bovine beta casein polymorphism in two dairy farms located in northern Italy. Ital J Food Saf. 2017 Sep 29;6(3):6904.
  • 14. He M, Sun J, Jiang ZQ, Yang YX. Effects of cow's milk beta-casein variants on symptoms of milk intolerance in Chinese adults: a multicentre, randomised controlled study. Nutr J. 2017;16(1):72.
  • 15. Jianqin S, Leiming X, Lu X, Yelland GW, Ni J, Clarke AJ. Effects of milk containing only A2 beta casein versus milk containing both A1 and A2 beta casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows' milk. Nutr J. 2016;15:35.

Expert Interviews

Dr Nancy Tan, Paediatrician, Paediatric Gastroenterologist:
Goodness of Breast Milk: sn-2 and A2

Learn More About Goodness of Breast Milk

Dr Ang Ai Tin, Paediatrician, Neonatologist:
Understanding more about sn-2 palmitate and A2 ß-casein