Gaining weight in social networks

The July 26 issue of the New England Journal of Medicine (see http://cme.nejm.org/) includes a paper by Christakis and Fowler from Harvard Medical School that reports on a social network analysis of the data of the Framingham Study (see http://www.nhlbi.nih.gov/about/framingham/). The paper shows that people's likelihood to become overweight is much higher when their friends, siblings and/or spouses become overweight. Neighbours' weight changes appeared to have no effects. The study thus suggests that obesity spreads in social networks. Recent reviews of the literature (see for example Ferreira et al. Obesity Reviews 2007;8(2):129-54 [ http://www.blackwellpublishing.com/journal.asp?ref=1467-7881&site=1] and Van der Horst et al. Health Education Research2007;22(2):203-26 [http://her.oxfordjournals.org/]) suggest that social environmental factors are important determinants of physical activity and nutrition behaviours. These studies suggest that more and better effort are needed to use social network approaches in obesity prevention. Promising initiatives such as the La Ville Sante (see http://www.teachers.tv/video/119 for a video presentation on this initiative) use a strong community approach with social networking to promote health behaviours in order to help people to prevent unnecessary weight gain.

Sedentary behaviour or physical activity?

Several studies indicate that people who spend a lot of time on sedentary activities, especially watching TV, are more likley to be overweight. This ralation between sedentary behaviour and weight status appears to be rather independent of the amount of physical activity people engage in. Indeed, people who do a lot of physical activities, may also engange in a lot of sedentary behaviour. Sport activities may make you tired and sit down! A study by Saskia te Velde and others published in BMC Public Health suggest that sedentary behaviours and sport activities cluster among teenage boys (see http://www.biomedcentral.com/content/pdf/1471-2458-7-16.pdf).

But what is a more important risk factor for becoming overweight, lack of physical activity or being sedentary? A recent study published in the International Journal of Behavioral Nutrition and Physical Activity (http://www.ijbnpa.org/) shows that 'screen time' (TV, video, computer) at age 15 did predict obesity at age 21, while medium and high intensity physical activity did not. This effect was strongest among girls (http://www.ijbnpa.org/content/pdf/1479-5868-4-26.pdf). This is one of very few longitudinal studies on this topic, and the results suggest that getting adolescents away from their screens is important for obesity prevention.

Culture is in the amniotic fluid…?

At a pre-conference workshop of the 10th European Nutrition Conference in Paris I was one of the speakers on Acquisition of Food-Related Behaviours in Children. The first speaker of the day, Luc Marlier from Strasbourg, France, gave a very interesting and amusing talk on environmental influences on food choice very early in life. He presented his research that clearly indicates that children already obtain food preferences before birth, based on exposure to odours in the amniotic fluid. To which odours the child is exposed before birth is dependent on the eating habits and food choices of the mother. He claimed, therefore, that cultural environmental influences on food choice are already apparent in the womb. During the rest of the day the acquisition of food preferences in children was explored from a genetics perspective, from a social psychology perspective and from a public health perspective, and the important roles of parents, schools and marketing in influencing children’s food choices was highlighted. The different presentations will be made available via the Danone Institute website www.danoneinstitute.org.

After a succesful ISBNPA conference: physical activity!

The sixth annual meeting of the International Society of Behavioral Nutrition and Physical Activity ended on June 23 with a closing session. Professor Tom Baranowski, the founder and first president of ISBNPA (on the right on the photo; the others are also former presidents of ISBNPA: Gaston Godin and Ron Kleinman), concluded that the conference was a succes with a record-high number of participants and presentations, with high-quality presentations addressing many key issues in behavioral nutrition and physical activity research. Tom Baranowski also stated that upcoming conferences should try to include more presentations on intervention studies, and that the society should continue to try to attract more researchers from countries and regions other that Western Europe, North America and Australia.

After the conference I partcipated in some intensive physical activity myself: a great 13-day bike tour through the westen part of Norway with my partner, Astrid (see how summer-like the higher mountains in Norway are in June). We cycled from Gol to Alesund and back, visiting the Sogne fjell and fjord and many other highlights.

The sixth ISBNPA conference is ongoing!

Yesterday the sixth annual meeting of the International Society of Behavioral Nutrition and Physical Activity (ISBNPA, see http://www.isbnpa.org/) has started in the Folket Huset conference center in Oslo, Norway. After professor Knut Inge Klepp as the chair of the local organising committee and myself as the incoming president of the society gave a brief word of welcome to all the delegates, Dr. Heath McDonald of Deakin University, Australia, gave a very interesting opening keynote on marketing to children. His key message was that a ban on advertising to children may not be a very effective way to help to prevention childhood obesity, since many other way of marketing are in place that are more effective and that will not suffer from advertising bans. After this keynote there was a very pleasant and lively opening reception.
This year’s ISBNPA meeting attracted a record-number of participants, over 500, compared to the 200-350 in earlier years. This is a great accomplishment. ISBNPA is growing into a serious society, also because the ISBNPA journal, the International Journal of Behavioral Nutrition and Physical Activity (see http://www.ijbnpa.org/) is now officially tracked to establish an official impact factor (the preliminary IF is > 3.0!).
Today the conference is nicely on track with a great keynote by professor Leanne Birch from Pen State University, USA, on parental and early childhood influences on children’s eating behaviors followed by different parallel sessions on behavioural nutrition and physical activity issues.
Many thanks to the local organisers, chaired by professor Knut Inge Klepp and strongly coordinated by Dr. Nanna Lien, for making this possible.

Diabetes solutions that care

Philips research organised a symposium on diabetes care

On June 14 I attended and presented at a symposium on diabetes care organised by Philips Research on the ‘high tech campus’ in Eindhoven: “Diabetes solutions that care”. The symposium was indeed mostly focussed on diabetes care with presentations on blood glucose monitoring and management, and new antidiabetic drugs. Different speakers expressed that there may be business in diabetes care, more than in prevention. For health insurance companies, for example, there is no incentive to aim at primary prevention of diabetes. However at the start of the day, Wim Wientjes great introductory presentation also addressed the importance of prevention and lifestyle changes. Wientjes was president of the Dutch Diabetes Federation, and is vice president of the International Diabetes Federation. Other presenters came from Germany, UK, and the Netherlands. Mine was the final presentation of the day. A bit strange that the importance of prevention gets most attention at the end… But it was an interesting day, not in the least because of the demonstrations of physical activity monitoring systems Philips is working on and that would be great as an objective basis for tailored health behaviour change feedback.

Research school CaRe met in Amsterdam

On Friday June 8 researchers from the CaRe research school had their annual retreat. This time the meeting was held in Amsterdam, hosted by the EMGO Institute. CaRe unites researchers from the VU University and Medical Center (EMGO Institute), Maastricht University, Nijmegen University, and the Netherlands Institute for Health Services Research (NIVEL) with an interest in research for trans and extramural health care, primary health care, prevention and health promotion. The theme this year was ‘Prevention Research’.

After Professor Guy Widdershoven, director of CaRe had opened the meeting with a brief overview of CaRe’s mission and goals, I had the honor of chairing the morning session. This morning session was focussed specifically on prevention of mental disorders and on mental health promotion. First Professor Nanne de Vries from Maastricht University build a case for careful planning and evidence-based practice in prevention, and for adopting a broader health promotion perspective in promotion of public mental health. He also illustrated once more the lack of governmental funding for prevention efforts.
Next Professor Pim Cuijpers (In the middle, in the yellow shirt), VU University and EMGO Institute, very clearly illustrated the importance of mental disorders as determinants of population health in the Netherlands. Anxiety disorders and depression are amongst the most prevalent disorders, causing substantial loss of quality of life and are responsible for more than 20% of total health care costs. He further argued that since treatment of mental disorders is certainly not always effective and relapse often occurs, prevention efforts should be intensified.
Heleen Riper (right to Pim in the picture) highlighted one very promising avenue for prevention efforts: web-based prevention programs. The Netherlands is among the countries with the highest internet access rates, and various evidence-based web-delivered programs are available for such disorders as depression, alcohol dependency and anxiety disorders.
Las but not least, our foreign guest, Professor Charles Reynolds (on the mid left, the man in the nice suit) from Pittsburgh University gave his address, in which he presented original research showing the effects of relapse prevention efforts on top of medical interventions for sustaining effects in depression treatment.
A lively round table discussion followed between the four speakers and the approximately 120 CaRe researchers.