Unless there is a diagnosis which is based on food or will affect food intake, for example diabetes or inflammatory bowel disease, doctors struggle to convey helpful information on diet.
Even then things are difficult because very few doctors have ever received detailed education about what constitutes a 'good diet' and how to convey diet information effectively to a patient.
Therefore, the advice many doctors will give is likely to be simplistic and not necessarily convincing for a patient.
The significance of a good day-to-day diet is not obvious and it would be unlikely for a GP to address diet unless it could be directly linked to the consultation.
Becoming overweight and obese is usually a rather simple and obvious mechanism: too much energy intake in relation to the energy output over a long enough period of time.
Although many people are more sedentary in normal daily activities than only a couple of decades ago, the quantity and quality of food intake is highly relevant for unhealthy weight gain.
Food is more processed and people have lost touch with preparing food themselves, which is critical for experiencing and understanding how food works.
When we talk of diet it often implies a conscious and only temporary effort to control food input, either in quantity or quality, whereas we should aim for a permanent change from unhealthy eating habits to a well-balanced food intake.
The successes of television programmes about 'good food' are only possible because there is a significant gap in the provision of healthcare and basic general knowledge.
The impact of these programmes needs to be evaluated but is quite likely to be relatively low in general, because the 'inverse care law' may apply: people who need it the least will pick up the advice but those who it need most will not.
The increasing discussion about the role of the GP in managing or tackling obesity displays a fundamental problem: treatment and rehabilitation of an obese person is a very complex and often inefficient process.
Therefore, it is probably unrealistic to achieve consistently successful outcomes with the current resources available in a primary care setting.
However, rather than giving up at this first hurdle and banning diet issues completely from the consultation, a first step could be to discuss it more proactively.
The aim would be to look into primary prevention of people who could be at risk of becoming obese, rather than treating those already affected.
There are some typical risk groups, such as children with overweight parents, women after pregnancy, or patients with mobility issues after injuries, which are likely to increase their weight. Patients in these categories may believe that they are powerless to stop the weight gain.
GPs need knowledge and experience to address weight issues. An interesting Dutch study from 2006 found that GPs are using five typical nutrition communication styles: informal, reference, motivational, confrontational and holistic.
It could be seen as an important step to reflect on one's preferred personal style and develop it further. The same study identified that GPs hardly provided efficient follow-up or maintenance advice.
It is more difficult for people to measure progress in good eating habits in comparison with doing more exercise.
Better eating should not have weight control as the only aim and outcome, although this is objective and can be proven on the scales.
The market for information regarding diets is frantic and confusing, often full of conflicting information.
If patients see their GP to ask which specific diet a health professional would recommend, then we would have fairly little to offer easily, apart perhaps from the advice to be careful with popular celebrity diets, crash diets or so-called detox diets, as they are rarely backed up sufficiently by scientific evidence and can be counterproductive.
Concepts of specific diets are not always fully understood by practising GPs so can be difficult to advise on.
A good option as a start is the guide 'So you want to lose weight for good' by the British Heart Foundation.
Assessing a patient's motivation for weight loss can be crucial to predict outcomes. It is surprising how little patients know about themselves.
Suggest keeping a food diary recording all food and drink intake as accurately as possible in quality and quantity.
This awareness exercise is likely to highlight any gross imbalance quickly, such as comfort eating.
A GP can make a decision to mention food more often in the consultation to indicate its essential part in life. This alone gives an important message to many patients.
Dr Jacobi is a salaried GP in York
This topic falls under section 5 of the GP Curriculum 'Healthy People: promoting health and preventing disease'.
1. You can only create interest and awareness in patients regarding diet if you are comfortable with the topic yourself. Research shows that GPs are lacking knowledge and experience in diet advice.
2. Reflect which one out of five main consultation styles regarding diet advice you are using and develop it further.
3. Target people at risk for weight issues as prevention rather than feeling unsuccessful with the already obese.
4. Consider being more proactive in simply mentioning food in the consultation and aim to maintain the topic in following consultations.
5. Assess motivation, interest and existing knowledge with some simple questions and check discipline by suggesting a food diary.
6. Make use of local and public resources and aim for consistent information and support.
- Identification of nutrition communication styles and strategies: a qualitative study among Dutch GPs, Van Dillen S M, Hiddink G J et al, Patient Educ Cons 2006 Oct; 63: 74-83.
- 'So you want to lose weight ... for good' British Heart Foundation.