Vitamin D intake before conception by fathers improves children’s growth

Vitamin D consumption by future fathers during the period before pregnancy can influence the growth and obesity risk of their children. In particular, the amount of vitamin D obtained from food by men is statistically associated with their offspring’s height and weight. Therefore, during the preconception period, not only the mothers’ dietary habits influence the baby’s development, but also the fathers’. Nutrition could act on the health and function of the cells that form sperm.

This emerges from new research conducted by Dr. Cilia Mejia-Lancheros and colleagues at University College Dublin (Ireland). The results were presented at the European Congress on Obesity held in Portugal last May.

The sunshine vitamin is important for growth and bone health

Vitamin D is a fat-soluble molecule that exists in two forms: cholecalciferol and ergocalciferol, and it performs many vital functions in the human body. The amount of vitamin D obtained from diet is often insufficient for daily needs, as few foods naturally contain it, including fatty fish, dried mushrooms, whole milk products, and eggs. 

About 90% of the vitamin D molecules present in the human body are produced thanks to skin exposure to the sun’s ultraviolet rays. The main function of vitamin D is to maintain normal blood calcium and phosphorus levels and promote calcium absorption, contributing to the formation and maintenance of bones and teeth. Vitamin D deficiency can cause rickets and osteomalacia, as well as other disorders unrelated to the skeletal system. 

Vitamin D is also very important for the proper functioning of the immune, respiratory, and cardiac systems. Several studies have shown that maternal vitamin D intake plays an important role in maintaining general and musculoskeletal health in children. However, little attention has been paid so far to the potential link between children’s growth and the vitamin D status of future fathers during the preconception period.

An unexpected discovery: paternal nutrition can influence children’s height and weight

The new analysis specifically investigated the relationship between vitamin D consumption in parental couples during the preconception period and their children’s height and weight measured at ages five and nine. The results suggested that fathers’ vitamin D intake was significantly associated with the height and weight of children at five years old. However, this association was statistically not significant when the offspring reached nine years of age. Surprisingly, the results showed no link between maternal vitamin D levels during the first and second trimesters of pregnancy and the height and weight of children at five or nine years. "One reason this might happen is that the father’s nutritional status may somehow influence the health, quality, and function of germ cells involved in reproduction," the researchers stated; "Therefore, maternal nutritional status might not be the only key factor for the development and healthy growth of children," they added. 

As is well known, skin exposure to sunlight is essential for the body to produce vitamin D. Thus, the study authors also considered the number of hours children spent outdoors during the summer. They found that spending 3 or more hours playing outside during weekends was correlated with greater height.

Some details of the study

The researchers analyzed data from the Lifeways Cross-Generation Cohort Study, a database collecting health information on children born in Ireland since 2001 and their parents. Height and weight measurements were available for 213 and 148 father-child pairs when the children were 5 and 9 years old, respectively. Information on paternal vitamin D intake was derived from dietary questionnaires. The study results showed that at age 5, the average height and weight of children were 112.12 cm and 20.95 kg, respectively, with paternal vitamin D intake averaging 3.46 μg per day during the preconception period. 

At age 9, average height and weight for the children were 138.61 cm and 34.09 kg, and paternal vitamin D intake was 1.25 μg per day. The association between fathers’ vitamin D intake during the three months before pregnancy and children’s height and weight was calculated using specific statistical analyses adjusted for potential confounders, including: father’s age, height, and weight; mother’s age, vitamin D levels, height, energy intake, and weight; child’s sex, age, vitamin D levels, energy intake, and physical outdoor activity during summer.

A study that will continue with further investigations 

The results showed that paternal vitamin D concentration is positively associated with children’s height and weight at age 5, paving the way for further research into family nutrition. In the coming months, the authors will collect additional data on father-child pairs, including anthropometric data, health, lifestyle, and behavior of the children involved in the study, also through adolescence, studying their health status and that of future generations.

Source: Mejia-Lancheros, et al., Paternal antenatal vitamin D intake is associated with offspring’s height and weight aged five and nine years in the Lifeways Cross-Generation Cohort Study, Ireland, 24th European Congress on Obesity (ECO2017), Porto, Portugal, May 17-20, 2017.