New facts have emerged about the people who were born in June, July and August.
The new research suggests that people born in the summer (equivalent
to peak rainy season in Nigeria) are more likely to be healthy than
those who arrive during other times of the year.
The phenomenon could be caused by mothers getting more sun in pregnancy – and passing on higher quantities of vitamin D to their unborn infant.
The phenomenon could be caused by mothers getting more sun in pregnancy – and passing on higher quantities of vitamin D to their unborn infant.
A study of almost half a million British adults found babies born in
June, July, and August were heavier at birth and taller as adults.
For the first time the research also revealed girls born in the
summer started puberty later – an indication of better health in adult
life.
Early puberty in girls has been linked with a higher risk of diabetes, heart disease or breast cancer.
Study author Dr. John Perry, of Cambridge University, said: “When you were conceived and born occurs largely “at random”.
“It’s not affected by social class, your parents’ ages or their
health – so looking for patterns with birth month is a powerful study
design to identify influences of the environment before birth.”
His team compared the growth and development of around 450,000 men
and women from the United Kingdom (UK) Biobank study – a major national
health resource that provides data on UK volunteers to shed light on the
development of diseases.
Perry explained: “This is the first time puberty timing has been
robustly linked to seasonality. We were surprised, and pleased, to see
how similar the patterns were on birth weight and puberty timing.
“Our results show birth month has a measurable effect on development
and health, but more work is needed to understand the mechanisms behind
this effect.”
Previous research has shown children born between June and October
are likely to be slightly taller and have bigger bones than winter-born
children – believed to be related to vitamin D exposure during
pregnancy.
Babies
born in autumn and winter are more likely to develop food allergies –
with sunlight exposure during pregnancy and vitamin D levels also
thought to play a role in this.
Asthma is also more common in autumn-born children – and one theory
for this is increased exposure to allergens, such as house dust mites,
during the first few months of life – because of the worse weather.
The latest findings, published in the journal Heliyon, declare birth
month affects both the weight of the newborn and when a girl starts
puberty.
Both of these have an impact on overall health in women as adults.
Furthermore, the environment in the womb leads to differences in early
life – including before birth – that can influence health in later life.
For the study, Perry and his colleagues looked at whether birth month
had an effect on birth weight, onset of puberty and adult height .
The team found that children born in the summer were slightly heavier
at birth, taller as adults and went through puberty slightly later than
those born in winter months.
Previous studies have reported certain season of birth effects such
as on birth weight and various other health outcomes so Perry and
colleagues decided to look more closely.
They believe the differences between babies born in summer and winter
could be down to how much sunlight the mother gets during pregnancy –
since that in part determines her vitamin D exposure.
Perry said: “We don’t know the mechanisms that cause these season of
birth patterns on birth weight, height and puberty timing. We need to
understand these mechanisms before our findings can be translated into
health benefits.
“We think vitamin D exposure is important and our findings will
hopefully encourage other research on the long-term effects of early
life vitamin D on puberty timing and health.”
– Culled from Guardian
