Data from an “unintended natural experiment from World War II” showed restricting sugar intake from conception through 1,000 days after birth was linked to a 35% lower risk of developing Type 2 diabetes and as much as 20% less risk of hypertension as adults. Low sugar intake by the mother prior to birth was enough to lower risks, but continued sugar restriction after birth increased the benefits.
The study appeared in Science and the lead author is Tadeja Gracner, University of Southern California. It was a collaboration between researchers at the McGill University in Montreal, the University of California, Berkeley, and USC Dornsife College of Letters, Arts and Sciences.
“Studying the long-term effects of added sugar on health is challenging,” says Gracner, senior economist at the USC Dornsife Center for Economic and Social Research. “It is hard to find situations where people are randomly exposed to different nutritional environments early in life and follow them for 50 to 60 years. The end of rationing provided us with a novel natural experiment to overcome these problems.”
The team examined how sugar rationing during World War II influenced long-term health outcomes. The United Kingdom introduced limits on sugar distribution in 1942 as part of its wartime food rationing program. Rationing ended in September 1953.
The researchers used contemporary data from the U.K. Biobank, a database of medical histories and genetic, lifestyle and other disease risk factors, to study the effect of those early-life sugar restrictions on health outcomes of adults conceived in the U.K. just before and after the end of wartime sugar rationing. The sample included 60,183 participants born between October 1951 and March 1956, and aged 51–66 when surveyed.
Sugar intake during rationing was about 8 teaspoons (40 grams) per day on average. When rationing ended, sugar and sweets consumption skyrocketed to about 16 teaspoons (80 grams) per day.
Notably, rationing did not involve extreme food deprivation overall. Diets generally appeared to have been, in fact, within today’s guidelines set by the U.S. Department of Agriculture and the World Health Organization, which recommend no added sugars for children under two and not more than 12 teaspoons (50g) of added sugar daily for adults.
The immediate and large increase in sugar consumption, but no other foods after rationing ended, created an interesting natural experiment.
The researchers identified those born around this time in the U.K. Biobank data collected over 50 years later. Using a very tight birth window around the end of sugar rationing allowed the authors to compare midlife health outcomes of otherwise similar birth cohorts.
While living through the period of sugar restriction during the first 1,000 days of life substantially lowered the risk of developing diabetes and hypertension, for those who were later diagnosed with either of those conditions, onset of disease was delayed by four years and two years, respectively.
Notably, exposure to sugar restrictions in utero alone was enough to lower risks, but disease protection increased postnatally once solids were likely introduced.
The magnitude of this effect is meaningful as it can save costs, extend life expectancy and, perhaps more importantly, quality of life, say the researchers.
Co-author Paul Gertler of UC Berkeley and the National Bureau of Economics Research adds: “Sugar early in life is the new tobacco, and we should treat it as such by holding food companies accountable to reformulate baby foods with healthier options and regulate the marketing and tax sugary foods targeted at kids.”
