New link between mother’s pregnancy diet and offspring’s chances of obesity
An international study published in Diabetes has shown for the first time that a mother’s diet during pregnancy can alter the function of her child’s DNA through a process called epigenetic change – effectively turning on a fat switch and leading to her child laying down more fat as it grows older. Researchers measured epigenetic changes in nearly 300 children at birth and showed that these strongly predicted the degree of obesity at six or nine years of age. This effect acts independently of how fat or thin the mother is and of the child’s weight at birth. While it is not yet clear exactly which foods have the greatest influence on the DNA of unborn babies, the study did find an association between lower carbohydrate intakes and the methylation of the gene. However, is it unknown whether the amount of carbohydrate the women ate was within a healthy range. Further research is needed to explore which food groups, if any, are associated with epigenetic changes.
Prof. Keith Godfrey
‘We have shown for the first time that susceptibility to obesity cannot simply be attributed to the combination of our genes and our lifestyle, but can be triggered by influences on a baby’s development in the womb, including what the mother ate, says lead author Prof. Keith Godfrey from the University of Southampton. ‘This study indicates that measures to prevent childhood obesity should be targeted on improving a mother’s nutrition and her baby’s development in the womb.’
Co-author Prof. Mark Hanson explains: ‘This study … strengthens the case for all women of reproductive age having greater access to nutritional, education and lifestyle support to improve the health of the next generation, and to reduce the risk of the conditions such as diabetes and heart disease which often follow obesity.’
Child obesity – it’s Mum and Dad who make a difference
Health programs to help overweight and obese kids commonly target the children themselves. The two-year follow-up findings for the HIKCUPS study published in Pediatrics show that the most effective treatment for young children is to give parents good quality advice and support to improve their family’s food habits. ‘You can achieve better results simply by targeting parents alone, even without the child’s involvement,’ says Prof Clare Collins, from the University of Newcastle.
In the randomised controlled trial, 165 overweight young children (aged 5–9) were allocated either to a parent-centered nutrition/lifestyle program, or a child-centered physical activity/skill program, or to both. The good news is that all the children became slimmer for their age (i.e. they gained less than half the weight for their age had they not been in the program). ‘The greatest effects were achieved through inclusion of a parent-centered diet program, indicating the importance of targeting parents within treatment and the possibility of targeting them exclusively in treating obese pre-pubertal children,’ conclude the authors.
‘We are not advocating stopping the great health programs currently targeting children, as educating our kids on healthy lifestyles is critically important,’ says co-author Assoc Prof Tony Okely. But ‘our results indicate that by targeting the parents predominately, we can make a huge difference to this global epidemic.’
Saturated fat, heart disease and why it might be OK to say ‘cheese please’
Most dietary guidelines around the world tell us we have to reduce our intake of saturated fat to reduce our risk of heart disease, but they don’t tell us what to put in its place. In Western diets, it’s generally replaced with carbohydrates – and often refined ones. But say Prof Arne Astrup and a panel of world experts in the American Journal of Clinical Nutrition ‘the evidence is consistent in finding that the risk of coronary heart disease (CHD) is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs)’ while ‘no clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index.’
They go on to say that while it’s more useful to give people dietary advice based on specific foods (e.g. cheese or red meat) rather than nutrients (e.g. protein, carbohydrate or fat) the evidence is limited. For example although there’s strong evidence that diets high in processed meats are linked to an increased risk of heart disease, there’s no consistent evidence that a high intake of dairy products is too. They write: ‘There is increasing evidence to support that the total matrix of a food is more important than just its fatty acid content when predicting the effect of a food on CHD risk, e.g., the effect of SFAs from cheese on blood lipids and CHD may be counterbalanced by the content of protein, calcium, or other components in cheese.’ You can read the whole report online HERE.
New Nutrisystem edition: The Low GI Cookbook
Nutrisystem provides home-delivered, low GI weight loss programs throughout North America. In case you don’t know about it (and we didn’t), the idea is to help make getting started on a healthy weight loss effort as easy as possible, by providing portion-controlled entrees (main meals for those outside the USA) and snacks in customised monthly shipments, along with a meal planner and other tools and support. ‘However, many customers worry about being able to manage their weight once they stop the program,’ says Karen Curtis, registered dietitian with the Nutrisystem R&D team. ‘They need to learn how to prepare low GI foods and practise portion control for themselves’. To help them navigate the transition, we partnered with Low GI Diet Cookbook authors Prof Jennie Brand-Miller, Kaye Foster-Powell and Dr Joanna McMillan to adapt their book for the program. The Low GI Cookbook helps you understand why the program works and shows you how to sustain your weight loss by continuing to eat the low GI way.’