Cry baby: Infant tears reveal nutrient deficiencies
Vitamin concentrations in infants were ascertained from tear and blood samples with tears shown to be as effective as the more traditional medium of blood.
Lead study author, Dr Khaksari, a research specialist at the Chemical Advanced Resolution Methods (ChARM) Laboratory at Michigan Technological University, and her team took samples from 15 four-month-old infants and their parents.
They focused on babies with a 100% liquid diet of formula or breast milk to garner further understanding between the connection between parent nutrition and infant nutrition.
Nutritional data garnered from parents also revealed additional insights into family’s intake of healthy foods.
In general, water-soluble vitamins were found at higher levels in the infants while fat-soluble vitamins were higher in parents.
An important observation noted that mothers tended to be more deficient across-the-board.
A correlation was observed between vitamin E and vitamin B levels in the tears of both parents and babies.
Formula-fed babies were the exception, with notably higher levels of B vitamins in their tears.
“Our goal was to seek the viability of establishing measurable units of tears for nutritional assessments," said Dr Khaksari. “Since tears contain vitamins, they might have real potential to replace other clinical tests."
Tears ‘less invasive’
Vitamins are convenient indicators of nutritional health because they are not manufactured by the body consequently they reflect the quality of dietary food sources.
Tears’ sample preparation and collection are considered less invasive when compared to procedures involving blood, which requires several millilitres and is an invasive sample.
Urine samples as another example suffer from hourly composition changes and require 24-hour sample collection for accuracy.
In discussing some of their findings, the study’s authors noted the influence of a breast-fed/bottle-fed approach along with diets, on vitamin concentrations.
“We observed the concentrations of these two vitamins (B1 and B3) to be higher in the serum of infants with the greater percentage of bottle-fed diet,” the study’s authors wrote.
“Also, breast-fed infants demonstrated stronger concentration correlations with their parents. The correlations between the vitamin concentrations of infants and parents proved that an infant's nutrition was dependent upon their parent's nutrition.”
Higher vitamin concentrations were found in the tears of participants with minimal tear production. This, they said suggested that the vitamin concentrations depend on tear flow rates.
Source: Experimental Eye Research
Published online ahead of print: doi.org/10.1016/j.exer.2016.12.007
“Determination of water-soluble and fat-soluble vitamins in tears and blood serum of infants and parents by liquid chromatography/mass spectrometry.”
Authors: Maryam Khaksari et al.