Almost from the moment they have given birth it seems new mothers are under heavy pressure to breastfeed their baby, with health experts long championing the health benefits of breastfeeding. In fact, breast-fed babies have been said to be at a lower risk of suffering with sudden infant death syndrome, have less infections in their early years. Moreover, there are said to be health benefits in the long-term, with breast-fed babies growing up to be less likely to develop asthma, be obese, have high blood pressure or high cholesterol and type 2 diabetes. However, all this could be thrown onto its head with the findings of a new study published in the Social Science & Medicine, which may finally help to shed the stigma of bottle-feeding a new-born baby and raises questions about previous studies that have supported and pushed for mother mothers to breastfeed, sometimes putting unfair pressure on mums to do this. Lead author of the study Dr Cynthia Colen, from Ohio State University, and fellow researchers analysed 665 families in which there were siblings fed differently during their early years.  In total, there was 8,237 children made up of 7,319 siblings and 1,773 ‘discordant’ sibling pairs; one was breastfed with the other was fed with bottled milk. In all of the families looked at, breastfeeding showed better outcomes for BMI, hyperactivity, maths, reading recognition, vocabulary word identification, digit recollection, scholastic competence and obesity. However, when the analysis was focused purely on siblings fed differently within the same families, researchers discovered that the scores demonstrating breast-feeding's positive benefits on 10 of the indicators were close to zero and therefore not deemed statistically significant. This means any health variances in those families may have happened by chance. The only health condition that was found to have a significant difference in regards to breast-fed and bottle-fed siblings was asthma. Dr Colen actually claims that breast-fed babies were actually at a higher risk for developing asthma later in their life. She said: “Many previous studies suffer from selection bias. They either do not or cannot statistically control for factors such as race, age, family income, mother's employment - things we know that can affect both breast-feeding and health outcomes. Mums with more resources - with higher levels of education and higher levels of income - and more flexibility in their daily schedules are more likely to breastfeed their children and do so for longer periods of time.” NHS guidance recommends new mothers to breastfeed for the initial six months (26 weeks) of a new-born’s life. Following this, breast milk alongside other food will “help them continue to grow and develop”, according to the NHS. Dr Colen added: “I'm not saying breastfeeding is not beneficial, especially for boosting nutrition and immunity in new-borns. But if we really want to improve maternal and child health, let's also focus on things that can really do that in the long term - like subsidised day care, better maternity leave policies and more employment opportunities for low-income mothers that pay a living wage, for example.”