Mention pregnancy and food in the same breath, and the common phrase of 'eating for two' will probably spring to mind. But a ground-breaking new study indicates this may be a worrying oversimplification.

Scientists have now warned that pregnant mothers who are clinically obese or consume too much fat or sugar may put their babies at a greater risk of heart disease and diabetes later in life. The stark results come as a staggering 63.8% of adults aged 18 and over are estimated to be overweight or obese in England, according to Government data.

"You’re born with all the heart cells you will ever have," said PhD candidate Melanie Bertossa, who led the University of South Australia study. "The heart doesn’t make enough new heart muscle cells after birth to repair any damage, so changes that negatively impact these cells before birth could persist for a lifetime.

"These permanent changes could cause a further decline in heart health once children reach adolescence and adulthood when the heart starts to age."

As part of the study, a group of female baboons were randomly assigned either a control diet or 'high- fat high-energy diet' nine months before conceiving a baby. Once they had conceived, scientists then waited 184 days for the fetuses to develop.

These were delivered by Caesarean section under anaesthesia and 'humanely' killed before their cardiac tissue was collected. Shockingly, results showed that the high-fat high-energy diet altered the fetus' thyroid hormones, and experts noted this may 'increase the risk of cardiometabolic disorders in later life in offspring born to these pregnancies'.

This includes hypertension, diabetes, obesity, and heart failure, with the latter referring to a type of heart disease. The British Heart Foundation claims that coronary heart disease is the trigger for around one in every six deaths worldwide.

Prior to the coronavirus pandemic, it had also been the leading global cause of death during the past 30 years. Betrossa continued: "There has been a long-standing debate as to whether high-fat diets induce a hyper- or hypothyroid state in the foetal heart. Our evidence points to the latter.

"We found that a maternal high-fat, high-energy diet reduced concentrations of the active thyroid hormone T3, which acts like a switch around late gestation, telling the foetal heart to start preparing for life after birth. Without this signal, the foetal heart develops differently."

Importantly, the concerning issues were identified in infants who had a normal birth weight, prompting the researchers to recommend that all babies undergo heart health checks. Senior author, Professor of Physiology Janna Morrison, explained: "Cardiometabolic health screening should be performed on all babies born from these types of pregnancies, not just those born too small or too large, with the goal being to detect heart disease risks earlier."

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