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Sourcing evidence-based nutrition information

Susan Holmes
BSc PhD SRN FRSH
Professor of Nursing
Head of the Centre for Nursing Research and Practice Development
Canterbury Christ Church University College, Kent

There is no doubt that nutrition is central to healthcare provision, and many government reports highlight the role of diet in the aetiology of several diseases, such as cancer, cardiovascular and cerebrovascular disease, and obesity.(1) Nutritional care and dietary advice are therefore advocated in both the prevention and management of disease.
The state-registered dietitian (SRD) is the ­recognised resource for providing expert nutritional guidance and information to those outside this specialist field, and community dietitians provide support within the community. However, their numbers are limited and their workload often exceeds their ability to provide effective support and advice to all patients. As a result, primary healthcare teams have assumed greater responsibility for this aspect of care in the community and are increasingly required to provide nutritional information or to advocate dietary change for their patients/clients; much of this work has fallen to nurses.
Current health policy clearly assumes that primary care practitioners will play a significant role in educating the public about dietary matters. This assumes that such practitioners are better informed about diet, nutrition and health than those they seek to serve, yet the evidence clearly indicates that this is not the case. Studies repeatedly show that nutrition has traditionally been afforded low priority in both nursing and medical education.(2) It is not surprising that medical students know little about nutrition, or that doctors, just like the general public, are readily misled by inaccurate nutritional advertising.(3) Studies also reveal widespread deficiencies in nurses' knowledge,(4) while many midwives acknowledge their inability to provide nutritional advice to pregnant women owing to ­inadequate knowledge.(5)
This suggests that many health practitioners are inadequately prepared to provide nutritional advice, and Barratt has demonstrated little difference in the diet-related knowledge and beliefs of health professionals and the general public.(6) Both groups turn to the media for advice regarding diet and health, yet regard much of this with scepticism and find it both confusing and contradictory. It is a matter of significant concern that professionals appear to rely on the same information sources as the population they serve; their professional status confers credibility on the advice they offer regardless of its accuracy. Professionals' lack of knowledge can make it difficult for them to evaluate the accuracy of nutritional information - some are deceived by spurious qualifications awarded by organisations pursuing their own agendas; others are deceived by, for example, the numerous "slimming diets" based on dubious theories of little or no scientific validity. Such "messages" require careful evaluation based on sound underlying knowledge. It is unfortunate that, in this context at least, the need for evidence-based practice appears to be overlooked.

Nutrition resources
There are many sources of reliable and credible nutritional information - SRDs and registered nutritionists, evidence-based journals, and a readily available supply of scientifically valid nutritional data on the internet. Some of this, supplied through organisations supported by particular industries, is regarded with suspicion, although such mistrust is misplaced since the industries concerned would destroy their credibility and defeat their objectives if the information provided was not valid.
One such site is Kellogg's (www.kelloggs.com), which is directed towards the general public and has a "healthy eating" focus related primarily to its own products.
Other sites represent a specific industry and thus provide information primarily related to that industry. An example of this is The Sugar Bureau (www.sugar-bureau.co.uk), which focuses primarily on increasing knowledge and understanding about the contribution of sugar and other carbohydrates to a healthy, balanced diet. Another site is the British Nutrition Foundation (www.nutrition.org.uk), a registered charity supported by the food industry that offers a comprehensive and authoritative source of objective information.
Further information can be obtained through professional organisations, such as the British Dietetic Association (www.bda.uk.com) and The Nutrition Society (www.nutsoc.org.uk), which, although providing information only about the organisations themselves, also offer many links to other useful sites. The Health Education Authority have set up the Thinkfast site (www.thinkfast.co.uk), which offers basic nutritional information related primarily to fast foods and is designed to help people choose a healthier diet and to reduce the incidence of coronary heart disease.
The American Dietetic Association (www. eatright.org) deals only with selected topics but offers links to other sites. One of these is provided by Tufts University (USA) (http:// navigator.tufts.edu); this is an interactive site claiming to be: "the fastest and most reliable source of sound nutritional information on the web"; it provides a rating guide to many different nutritional sites and enables direct access to most.
If, however, the question relates to food in general rather than to nutrition, the International Food Information Centre (http://ific.org) provides a stated viewpoint on selected topics, while the Institute of Food Science and Technology (www.ifst.org.uk) will provide a UK view on a few specific issues, even if this tends to be "lost" in a mass of information - its statements on BSE (bovine spongioform encephalopathy, or mad cow disease) or genetically- modified foods, for example, are quite overwhelming and far too comprehensive for practical use.
 
Conclusion
This brief article has shown that, in this context at least, the evidence required to support clinical practice is widely available and readily accessible; there are numerous sources of reliable information. The difficulty is that, as in other areas of practice, individual expertise is rarely questioned and practitioners believe that they "know" what is needed. Unfortunately this is not always the case, especially among those whose training provided little nutritional information. It therefore behoves all practitioners to take steps to validate their beliefs and to ensure that the advice offered to patients/clients is based on the best available evidence. The links between diet and health are now better understood than ever before; modern information technology has made them readily available to all practitioners so that patients need no longer be provided with ­spurious nutritional advice.

References

  1. Department of Health. The health of the nation: a strategy for health in England. London: HMSO; 1992.
  2. Department of Health. Nutrition: core curriculum for nutrition in the education of health professionals. London: DoH; 1994.
  3. Philen RM, Ortiz DI, Auerbach SB, Falk H. Survey of advertising for ­nutritional supplements in health and body building magazines. JAMA 1992;268:1008-11.
  4. Perry L. Nutrition: a hard nut to crack. An exploration of the knowledge, attitudes and activities of qualified nurses in relation to ­nutritional nursing care. J Clin Nurs 1997;6:315-24.
  5. Mulliner CM, Spiby H, Fraser RB. A study exploring midwives' education in, knowledge of and attitudes to nutrition in pregnancy. Midwifery 1995;11:37-41.
  6. Barratt J. Diet-related knowledge, beliefs and actions of health ­professionals compared with the general population: an investigation in a community trust. J Hum Nutr Dietet 2001;14:25-32.

Resources
British Dietetic Association
5th Floor, Charles House
148/9 Great Charles Street Queensway
Birmingham B3 3HT
T:0121 200 8080
F:0121 200 8681
W:www.bda.uk.com

British Nutrition Foundation  
High Holborn House
52-54 High Holborn  
London WC1V 6RQ
T:020 7404 6504  
F:020 7404 6747  
W:www.nutrition.org.uk

Health Development Agency
Trevelyan House
30 Great Peter Street
London SW1P 2HW
T:020 7222 5300
F:020 7413 8900
W:www.hda-online.org.uk

Energise Nutrition Limited
PO Box 244
Woking
Surrey GU22 7FD
T:01483 728470
F:01483 751769
W:www.energise.co.uk

Our Healthier Nation
W:www.ohn.gov.uk

BBC Online
W:www.bbc.co.uk/health/nutrition