Babies born in winter are bigger, brighter and more successful

The weather may be gloomy but the outlook is sunny for boys and girls who arrive now, major new research reveals

For centuries astrologers have sworn that the time of year a baby is born plots the course its life will take. Now extensive research conducted over a seven-year period appears to prove that babies born in the winter are more likely to grow into big, bright and successful adults than their summer counterparts.

The study, which will be published this week, was led by scientists at Harvard University and monitored the development of 21,000 boys and girls worldwide. It shows that there were large seasonal variations when it came to weight, length, height, head size and mental ability.

Researchers believe that the effects on the pregnant mother and the growing foetus of seasonal variations in diet, hormones, temperature, exposure to sunlight and viruses and other infections may influence a baby's characteristics.

The American and Australian psychiatrists and anthropologists from Harvard and Queensland universities measured the children and carried out mental and motor tests at birth, at eight months, and at four and seven years.

Compared to summer births, those born in winter were significantly longer at birth, and were heavier, taller and had larger head circumference at age seven. They also had higher scores in a series of intelligence exercises. By the age of seven, winter- and spring-born children were 210g heavier, 0.19cm taller, and had head circumferences significantly larger than summer and autumn-born children. The results also show that babies born in the winter were the longest, while winter- and spring-borns weighed the most at the age of seven and were also the tallest.

The researchers, whose work appears this week in the medical journal Schizophrenia Research, conclude: "The overall pattern of findings is that winter/spring babies are both 'bigger' on the anthropometric variables and 'smarter' on the selected neurocognitive variables."

The new study is the latest - and largest - in a series of projects worldwide aimed at evaluating the effect of the seasons on human health, longevity and physical and intellectual development. In 2002, scientists at Germany's prestigious Max Planck Institute for Demographic Research announced that people born in the autumn live longer than those born in spring, and do not become as ill in old age.

Studying census data from Denmark, Austria and Australia, the institute also revealed a seasonal link to life expectancy for those older than 50. In Austria, for example, it was found that adults born between October and December lived some seven months longer that those born between April and June.

Dietary changes and seasonal infections are thought to be at the heart of the phenomenon. "A mother giving birth in spring spends the last phase of her pregnancy in winter, when she will eat fewer vitamins," said Gabriele Doblhammer, one of the scientists who carried out the research. "When she stops breast-feeding and starts giving her baby normal food, it is in the hot weeks of summer - when babies are prone to infections of the digestive system."

The season of birth can also influence whether a person is an optimist or pessimist. Yet it is the summer's babies that have a brighter outlook than winter-born grumblers.

The American and Australian researchers offer a number of explanations for such differences in the early years of life. One theory is that foetal exposure to changing seasonal factors such as temperature, rainfall and ultraviolet radiation may be responsible.

Start your day with The Independent, sign up for daily news emails
ebooks
ebooksA special investigation by Andy McSmith
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Photographer / Floorplanner / Domestic Energy Assessor

£16000 - £25000 per annum: Recruitment Genius: A Photographer/ Floor planner /...

Ashdown Group: Front-End Developer - Surrey - £40,000

£30000 - £40000 per annum: Ashdown Group: Front-End Developer - Guildford/Craw...

Recruitment Genius: Customer Service Assistant

£13500 - £15000 per annum: Recruitment Genius: A Customer Service Assistant is...

Recruitment Genius: Sales Executive - OTE £35,000

£16000 - £35000 per annum: Recruitment Genius: An ambitious and motivated Sale...

Day In a Page

Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

How a costume drama became a Sunday night staple
Miliband promises no stamp duty for first-time buyers as he pushes Tories on housing

Miliband promises no stamp duty for first-time buyers

Labour leader pushes Tories on housing
Aviation history is littered with grand failures - from the the Bristol Brabazon to Concorde - but what went wrong with the SuperJumbo?

Aviation history is littered with grand failures

But what went wrong with the SuperJumbo?
Fear of Putin, Islamists and immigration is giving rise to a new generation of Soviet-style 'iron curtains' right across Europe

Fortress Europe?

Fear of Putin, Islamists and immigration is giving rise to a new generation of 'iron curtains'
Never mind what you're wearing, it's what you're reclining on

Never mind what you're wearing

It's what you're reclining on that matters
General Election 2015: Chuka Umunna on the benefits of immigration, humility – and his leader Ed Miliband

Chuka Umunna: A virus of racism runs through Ukip

The shadow business secretary on the benefits of immigration, humility – and his leader Ed Miliband
Yemen crisis: This exotic war will soon become Europe's problem

Yemen's exotic war will soon affect Europe

Terrorism and boatloads of desperate migrants will be the outcome of the Saudi air campaign, says Patrick Cockburn
Marginal Streets project aims to document voters in the run-up to the General Election

Marginal Streets project documents voters

Independent photographers Joseph Fox and Orlando Gili are uploading two portraits of constituents to their website for each day of the campaign
Game of Thrones: Visit the real-life kingdom of Westeros to see where violent history ends and telly tourism begins

The real-life kingdom of Westeros

Is there something a little uncomfortable about Game of Thrones shooting in Northern Ireland?
How to survive a social-media mauling, by the tough women of Twitter

How to survive a Twitter mauling

Mary Beard, Caroline Criado-Perez, Louise Mensch, Bunny La Roche and Courtney Barrasford reveal how to trounce the trolls
Gallipoli centenary: At dawn, the young remember the young who perished in one of the First World War's bloodiest battles

At dawn, the young remember the young

A century ago, soldiers of the Empire – many no more than boys – spilt on to Gallipoli’s beaches. On this 100th Anzac Day, there are personal, poetic tributes to their sacrifice
Dissent is slowly building against the billions spent on presidential campaigns – even among politicians themselves

Follow the money as never before

Dissent is slowly building against the billions spent on presidential campaigns – even among politicians themselves, reports Rupert Cornwell
Samuel West interview: The actor and director on austerity, unionisation, and not mentioning his famous parents

Samuel West interview

The actor and director on austerity, unionisation, and not mentioning his famous parents
General Election 2015: Imagine if the leading political parties were fashion labels

Imagine if the leading political parties were fashion labels

Fashion editor, Alexander Fury, on what the leaders' appearances tell us about them
Phumzile Mlambo-Ngcuka: Home can be the unsafest place for women

Phumzile Mlambo-Ngcuka: Home can be the unsafest place for women

The architect of the HeForShe movement and head of UN Women on the world's failure to combat domestic violence