Unit 2: Nutritional Requirements of the Preterm Infant

Vitamin C or ascorbic acid can be found in citrus fruits, tomatoes, acerola fruit, strawberries, potatoes, broccoli, spinach, etc. Vitamin C is involved in a number of metabolic pathways including fatty acid transport, synthesis of carnitine, collagen synthesis, neurotransmitters activation, synthesis of noradrenaline from dopamine, and prostaglandin metabolism. Vitamin C is also a potent antioxidant (IOM 2000). In the fetal and neonatal brain, vitamin C is found in high concentrations. Its absorption occurs actively in the small intestine but the body is not able to store it for long (Leaf & Lansdowne 2014).

The classical clinical manifestation of vitamin C deficiency, scurvy, is rarely seen nowadays. However, it still occurs in severely malnourished individuals, drug and alcohol abusers. Scurvy symptoms have been described since the classical periods BC. It is characterized by bleeding gums, weakness, fatigue, neuropathy, petechia, arthralgia and edema (Jacob 2000). Vitamin C measurements are done either in plasma serum or white blood cells concentration. Scurvy symptoms generally occur when vitamin C serum concentration is less than 0.2 mg/dl (IOM 2000).

Water-soluble Vitamins - Placental Transfer and Status at Preterm Birth

In the fetus water soluble vitamins are actively transferred through the placenta. Therefore, at birth, newborns (term or preterm) present with relatively high vitamin concentrations. After birth, however, concentrations fall rapidly if intake is not promptly assured, due to little or lack of vitamin storage. Preterm infants will need a steady vitamin supply soon after birth, since they have a relatively high metabolic rate and rapid tissue turnover for growth.