Cutting the amount of sugar children get in the womb and as toddlers can protect them against diabetes and high blood pressure in adulthood, research suggests.
The finding reveals a critical period for healthy nutrition in the first 1,000 days of life as babies initially absorb nutrients from their mother and move on to formulas and infant foods.
Scientists found that restricting sugar intake to levels in dietary guidelines in early life was linked to a 35% drop in rates of type 2 diabetes in middle age and a 20% fall in high blood pressure.
A low-sugar diet also appeared to delay onset of the chronic diseases, with diabetes and high blood pressure arising four and two years later respectively in people who had little sugar at the start of life compared with those who consumed much more.
Tadeja Gračner, at the University of Southern California in Los Angeles, said: “Exposure to a relatively low-sugar environment in utero and early childhood significantly reduces the diabetes and hypertension risk decades later, as well as delays their onset.”
The researchers took advantage of a natural experiment in the UK when a decade of postwar sugar and sweets rationing ended in 1953. During rationing, the sugar allowance was comparable to levels set in modern dietary guidelines, but consumption nearly doubled soon after the restrictions lifted, from about 40g to 80g a day.
Using UK Biobank data, the scientists compared health in middle age for 38,000 people conceived and born during rationing and 22,000 people conceived soon afterwards.
Their analysis, published in Science, found that rates of diabetes and high blood pressure were substantially lower for those who were conceived and reached two years old during sugar rationing. Time spent in the womb accounted for about one-third of the reduction in risk.
The NHS recommends that free sugars – those added to food and drinks and found naturally in honeys, syrups and unsweetened fruit and vegetable drinks – should not make up more than 5% of daily calories, equivalent to 30g or seven sugar cubes for an adult. There is no guideline for children under four, but they are advised to avoid sugar-sweetened drinks and food with added sugar. On average, Britons consume about twice the recommended daily amount.
Gračner said: “We all want to improve our health and give our children the best start in life, and reducing added sugar early is a powerful step in that direction. But it’s far from easy. Added sugar is everywhere, even in baby and toddler foods, and children are bombarded with TV ads for sugary snacks.
“While improving nutritional literacy among parents and caregivers is key, we should also hold companies accountable to reformulate baby foods with healthier options and regulate the marketing and pricing of sugary foods targeted at kids. With better information, environment and the right incentives, parents can more easily reduce sugar exposure for their kids and themselves.”
Prof Keith Godfrey, from the University of Southampton, said: “This is convincing new evidence, providing further support that reducing exposure of the unborn baby and newborn infant to sugar has lasting benefits that include lowering the risk of diabetes and high blood pressure in later adulthood.
“The findings are in keeping with our research showing lower rates of obesity in the children of mothers who eat low glycaemic index foods during pregnancy that are digested and absorbed more slowly, causing a slower rise in blood sugar levels.”
Dr Nina Rogers, a research fellow at the London School of Hygiene and Tropical Medicine, said: “There’s strong evidence that high levels of sugar consumption in children and adults can contribute to poor health, but this new study highlights the importance of a diet low in added sugars at the earliest stages of the life course, during the prenatal period and the first years of life, to protect against poor health in midlife.
“The findings suggest that public health interventions should be developed for this critical period of development to enable easy access to affordable high-quality low-sugar diets.”