Nutrition A to Z

16 min read /
Nutrition A to Z

An overview on important nutrition terms.

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z
Topic Brief Description
A alpha-lactalbumin

alpha-lactalbumin is a type of whey protein1. It participates in lactose synthesis in the mammary gland and constitutes 20-25% of total protein in human milk2. This protein contributes substantially to the amino acid requirements of infants2.

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Hot Science - Reduced risk of atopic dermatitis with an α-lactalbumin-enriched and symbiotic-supplemented infant formula


Bovine milk oligosaccharides (BMOs) are bioactive and belong to the carbohydrate component of bovine milk, where the most abundant acidic BMO in colostrum is 3-sialyl-lactose (3’SL). Many BMOs have chemical structures similar to human milk oligosaccharides (HMOs) and therefore there was discussion that BMOs may have similar functional attributes as HMOs, such as acting as a competitor inhibitor for pathogens on intestinal epithelial surfaces3.

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Bulletin 2018 Issue 3 – Discovering bovine milk oligosaccharides (BMOs)

C Casein

Casein serves as an efficient nutrient supply by slowly releasing amino acids into the blood stream4. The β-casein subtype is a major protein in bovine milk, where two major genetic variant exists (A1 and A2 types)5. There are differences in gastrointestinal responses after consumption of A1 and A2 β-casein in adults6. This has been attributed to the bioactive opioid peptide β-casomorphin 7 (BCM-7) that is released from A1 β-casein during digestion, which may slow gut motility and is associated with disease risk6,7.

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Docosahexaenoic acid (DHA) is a long-chain polyunsaturated fatty acid which plays a critical role in normal retinal and brain development of fetus and the first two years of life. DHA can be found in varying amounts from milk, fish and marine algae8.

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WNSC Hong Kong Info Card 2017 Issue 1 – DHA Fact Sheet

E Epigenetics

Literally translates as “above the genome”, Epigenetics is the study of heritable phenotype changes without alteration in DNA sequencing. Epigenetic coding involves an array of mechanism that alters gene expressions such as DNA methylation. Nutrition in early life plays its role as a critical determinant of epigenetic coding by asserting long-lasting impacts on gene expression involving predisposition of metabolic diseases (e.g. obesity and diabetes) across generations9.

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F Folic acid

Folic acid, the synthetic form of folate, is a vitamin B commonly used in supplements and fortified foods such as rice, pasta, bread, and cereals. During early prenatal development, folic acid helps form the neural tube and prevent major birth defects such as anencephaly and spina bifida10.

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G Glycemic Index (GI)

On a scale of 0 to 100, Glycemic Index (GI) measures how fast a food causes blood glucose levels to rise. The higher the GI, the more rapidly a food is being digested and absorbed. A diet with mostly low-GI foods is often higher in fiber, protein and/or fat, helping to achieve a more balanced diet and healthy weight11.

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WNSC Hong Kong Info Card 2016 Issue 4 – All About Dietary Fiber


Human milk oligosaccharides (HMOs) are a family of unconjugated glycans in human milk, the third most abundant human milk solid component after lactose and lipids12,13. HMOs have various functions including: i) ability to shape a positive intestinal microbiota ii) soluble decoy receptors for pathogens iii) prevention of pathogen attachment to intestinal mucosal surfaces iv) modulation of epithelial and immune cell responses12.

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I Iodine

Iodine is a vital component of thyroid hormones thyroxine (T4) and triiodothyronine (T3), of which the maternal levels affect proper fetal growth and neurological development during pregnancy and after birth. On top of a balanced diet, all women are advised to take 150 mcg and 220 mcg of iodine daily during pregnancy and lactation respectively. Women with thyroid disorder must consult their healthcare professionals before starting supplementations14.

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J Juice

Despite being a source of vitamin C, fruit juice is generally not recommended for infants < 1 year of age unless clinically indicated due to its high sugar content and associated risk of increased caloric intake and tooth decay. It also lacks various nutrients (e.g. magnesium and protein) that can be found in milk. The American Academy of Pediatrics recommends pediatricians to advocate the reduction of juice consumption in young children and the elimination of it in children with inappropriate weight gain15.

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K Ketogenic diet

Ketogenic diet generally refers to an eating pattern that is very low in carbohydrate, moderate in protein, and high in fat. With fat being the main source of energy consumed, the human body goes through ketosis and produces ketone bodies as metabolic by-products. Current research supports ketogenic diet as a medical intervention for some pediatric cases of epilepsy, yet only under the advice and cautious monitoring by a full medical team involving neurologists and dietitians16.

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L Lacto-N-neotetraose (LNnT)

One of the commonly found human milk oligosaccharide (HMO) along with 2’-fucosyllactose (2’-FL)17. HMOs have antiadhesive antimicrobial properties and may contribute to the lower incidence of intestinal, upper respiratory and urinary tract infections in breastfed infants12.

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M Mastitis

Mastitis refers to the localized, painful inflammation of the breast. The principle causes of mastitis are milk stasis and infection18. Treatments include effect milk removal, antibiotic therapy, and symptomatic treatment such as ibuprofen and bed rest. According to a prospective cohort study in 2014, the reported rate of mastitis was 6.3% among Chinese women19 and mastitis is one of the reasons for breastfeeding cessation during the first six months among Chinese mothers20.

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N Neurons

Neurons are nerve cells that send and receive nerve impulses and signals21. Overall, there are more than one hundred billion neurons in the adult brain, comprising thousands of different types21. Nutrients such as omega-3 fatty acids, vitamin B12, iron, iodine and zinc are essential to the normal growth and functioning of neurons.

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O Oligofructose  

Oligofructose is a type of dietary fibre in plants, and a prebiotic that can stimulate the growth of beneficial gut bifidobacteria, which may induce health benefits to the host23-25. It resists digestion in the upper gastrointestinal tract and gets fermented in the colon to support bifidobacteria growth, where laxation may improve from the increased microbial biomass25.

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P Phospholipids

Phospholipids are the structural components of human cell membranes26. Major phospholipids present in human milk, including sphingomyelin (SM), play an important role in neurocognitive processes such as the formation of myelin sheaths27-29. Dietary sources of phospholipids include eggs, lean meats, fish, cereal grains, etc30.

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Q Quinones

Derivatives of quinones are commonly present in biologically active molecules. Phylloquinone, also known as Vitamin K1, is found in abundance in green leafy vegetables. Menaquinone, Vitamin K2, is the main storage form K in animals which requires anaerobic conversion by the gut microbiota in our body. By facilitating the function of calcium-binding proteins, both forms of vitamin K are critical in achieving blood hemostasis and optimal bone and heart health31.

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R Recommended Dietary Allowance (RDA)

Established by the Food and Nutrition Board of the Institute of Medicine, Recommended Dietary Allowance (RDA) is the set of nutrient-based reference values which represent the average daily level of intake sufficient to meet the nutrient requirements of nearly all (97-98%) healthy individuals. For example, the RDA of folate for pregnant women of all ages is 600 mcg per day32.

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S sn-2 palmitate

Palmitic acid constitutes 20-25% of total fatty acids in human milk, of which 70% is esterified to the sn-2 position of the milk triacylglycerols (sn-2 palmitate) and is well absorbed33,34. In contrary, palmitic acid esterified to the sn-1 or sn-3 positions will result in intestinal calcium binding, forming fatty acid calcium soaps that are excreted in feces, leading to hard stools and calcium loss33.

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T Taurine

Being one of the most abundant amino sulfonic acids in the brain, retina and muscles, Animal studies found that taurine contributes to a wide range of physiological processes including brain development by activating stem cells to differentiate into neurons. Common dietary sources include meat and seafoods35.

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Uridine-5’-phosphate (UMP) is a type of nucleotide and serves as one of the building blocks for RNA and DNA. Nucleotides also play important roles in msany specific biological processes such as cellular signaling. UMP is found in abundance in human milk to support the need of rapidly developing tissues in infants to function properly, including the lymph, gastrointestinal, and blood cell systems36.

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V Vitamins

Vitamins are essential nutrients that support various physiological processes in our body such as nerve function, digestion, immunity, etc. Vitamins A, D, E, and K are fat-soluble while Vitamins B and C are water-soluble. Each serving its unique biological functions, vitamins are to be consumed in specific recommended levels to prevent symptoms of deficiency or excess37.

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W Whey

Whey proteins have high biological value, meaning the body can efficiently utilize the protein after consumption and it supplies ample amounts of essential amino acids4. Examples of whey protein include, alpha-lactalbumin, glycomacropeptide and lactoferrin37. These proteins have a diverse array of functional properties that may affect different biological processes and organ systems, including bone growth, muscle strength, would heeling and mood regulation38.

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X Xanthophyll

Xanthophylls is a category of fat-soluble and oxygen-containing carotenoid pigments, responsible for the color of the yellow, orange, and red hues of various plant species39. Lutein, mostly abundant in dark leafy vegetables, is an example of xanthophyll known to accumulate in the macula of the human retina40.

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Y Yolk

The yolk of an egg is a good source of numerous nutrients including choline which helps modulate gene expression, cell membrane signaling and also early brain development41. While eggs are commonly known for its high cholesterol content, current research provides no sufficient evidence to suggest the association of egg intake with increased risk of cardiovascular diseases42, nor a quantitative limit for dietary cholesterol43.

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Z Zinc

Zinc is a mineral present in all body tissues and fluids, with a central role in the immune system affecting a number of aspects of cellular and humoral immunity44. A cause and effect relationship has been established between dietary intake of zinc and normal function of the immune system, protection from oxidative damage, maintenance of normal bone and eye health45. Deficiency may lead to reduced growth rate and impaired immune defense44.

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