People born in the summer are more likely to be healthy than those who arrive during other times of the year, new research suggests. 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 UK Biobank study - a major national health resource that provides data on UK volunteers to shed light on the development of diseases. 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 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. 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. 他们认为,造成夏季和冬季出生的宝宝之间的区别的原因就是他们在妈妈孕期受到的日照不同,因为那在某种程度上决定了她所吸收的维生素D。 As early as the 1930s researchers noticed children born in winter were more prone to health problems later in life - slower growth, mental illness and even early death. Among the proposed explanations were diseases, harsh temperatures and higher pollution levels associated with winter when those expectant mothers and near-term foetuses might be most vulnerable. But being born in summer can have drawbacks - such as an increased risk of short-sightedness. It's thought sunshine interferes with the delicate development of the eye - making focusing difficult and distant objects appear blurred. 英文来源:每日邮报 |
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