Between February 2008 and February 2009, 500 infant-mother pairs in Bhaktapur, Nepal were randomly selected in this nutritional survey. The dietary intake, nutritional status of several nutrients, growth, and breastfeeding habits were measured in both the women and their infants.The objective of this first phase was to estimate the intake and status of several nutrients in relation to breastfeeding. These mother-child pairs were revisited around the child's fifth birthday when growth, diet, and neurodevelopment was measured. The objective of this phase was to create a cohort study where factors in infancy could be related with health outcomes and development 5 years later.

Over a period of one year, a total of 500 lactating (encompassing both exclusive and partial breastfeeding) women were enrolled in the study and completed the first 24-hour dietary recall. The women attended a hospital for physical examination, dietary interview, and blood sampling. Blood samples were also collected from their infants who also went through a detailed clinical examination

The blood samples from mothers and infant pairs were collected approximately one week apart. The blood was spun down, plasma separated and transferred into storage vials immediately. Plasma and blood pellets were stored in cryovials at -70 until analysis.

All women were also requested to provide one breast milk and one urine sample.

Plasma, blood pellet, urine, and breast milk was stored at -70 degrees celcius until analysis.

Plasma was analyzed for iron, transferrin receptor, ferritin, cobalamin, folate, vitamin A, vitamin D, vitamin E, several amino acids and other micronutrient related metabolites.

The breast milk will be analyzed for iodine, fatty acids, and several B vitamins

The urine was analyzed for iodine.

In phase 2, after 5 years we revisited the mother-child pairs and measured growth, diet, food security, and neurodevelopment.

Inclusion Criteria:

• availability of consent
• no ongoing illness
• resides in the selected cluster
• that household information could be obtained
• that the mother was lactating

Exclusion Criteria:

• refused blood sampling
• chronic illness

A cross-sectional survey was carried out and 500 healthy lactating women (17-44 years old) were randomly selected from Bhaktapur municipality, Nepal. Bhaktapur is an urban area located 15 km east of the capital Kathmandu and was chosen because of the diversity of this population spanning all socio-economic strata, providing a unique opportunity to explore dietary variation.

Data can be requested by contacting the principal investigator (Tor Strand) or one of the other investigators.