Research co-author Dr Deborah M Sloboda, PhD, Senior Research Fellow, Liggins Institute and Deputy Director, National Research Centre for Growth and Development comments on the research:
“In our study, Dr Mark Vickers and I examined pregnant rats that were allocated to receive either water or a fructose solution designed to provide 20 percent of caloric intake from fructose. Female fetuses, but not male fetuses, in the fructose-fed rats had higher leptin, fructose and blood glucose levels than their control counterparts. Male and female offspring of fructose-fed rats both showed higher plasma fructose levels and were hypoinsulinemic. We also found that the placenta of female fetuses in the fructose-fed rats were lighter than the female fetuses in the control group.
“Our study is unique as it is the first time that it has been suggested in an animal model, that female and male fetuses react differently to maternal fructose consumption, and that these sex-specific changes may be associated with changes in placental development.
“We believe that further studies are now critical to establish the long term effects of maternal fructose intake on the health and well-being of offspring and whether this study’s observed sex differences elicit different risk profiles for metabolic disease into the post-weaning period. Dr Vickers is currently conducting a follow-up study in rats.”
Anna Sloan, dietitian, North Shore Hospital comments on the Herald’s coverage:
This headline and statements such as “An expectant mother could be putting her unborn child at risk by drinking as little as three glasses of juice a day or eating five apples” are misleading and contributes to mixed messages regarding ‘healthy’ food.
The article would have been more balanced to clarify if it was pure fructose used in the Liggins research or high fructose corn syrup (HFCS), and to also mention that most fructose in the New Zealand diet comes not from fresh fruit, but from soft drinks and sweets.
Carbonated-beverage (i.e. soft-drink) consumption in New Zealand has continued to steadily increase and we are now the 9th highest consumers in the developing world. This means that on average each NZer consumes around 84.2litres/year (230ml/day) (with some people drinking 0mls/day and some having up to or more than 1.5litres). This is equivalent to 0g-43.g fructose/day (or 9.5g fructose/can of soft drink). Compare this to 6.8g of fructose from one apple which also contains essential vitamins and fibre.
Furthermore in the latest National Nutrition Survey only 56% of the female population were achieving the recommended intake of 2 serves fruit/day (with the majority of these not within the age of reproduction). The fruit consumed most often at least once per week by the New Zealand population was bananas followed by apples.
While it is possible to drink three glasses of juice/day the relative risk from fruit is much lower than from other dietary sources. Pregnant women should be encouraged to avoid soft drinks and excessive amounts of fruit juice and eat a variety of fruit each day.
1. Global Market Information Database, published by Euromonitor – : Euromonitor International is a global market research company specialising in industries, countries and consumers.
2. National Nutrition Survey1999, New Zealand Ministry of Health
3. Emme Chacko, Ingrid McDuff and Rod Jackson, Replacing sugar-based soft drinks with sugar-free alternatives could slow the progress of the obesity epidemic: have your Coke® and drink it too. Journal of the New Zealand Medical Association, 24-October-2003, Vol 116 No 1184