Ideas about food and health are sometimes developed by those who seek power or money. These people may use a fragment of evidence or partial truth which they develop beyond all scientific justification, to enhance their credibility. They encourage people to believe that their health depends on having a certain food, so that they are more likely to buy that food or product. Such foods may have a place, even an important one, in a healthy diet, but it is also clear that many foods are not essential because the essential nutrients can be found in a range of foods. For example,'health' food shops offer many foods such as wholegrain cereals, legumes, dried fruits and nuts, which are lower in fat, particularly saturated fat, and contain less sugar and salt and more dietary fibre than many processed foods. However, these foods are also available, generally at lower prices, in most supermarkets.

If people are persuaded that their diet is lacking in a particular vitamin or mineral or some other nutrient they may believe they need nutrient supplements, like vitamin pills. Unfounded fears about the food supply in countries like Australia have contributed to the use, even abuse, of nutrient supplements on a regular basis by at least 20 per cent of the adult population. In our society we can afford to demand high quality in our food supply. But we should not allow ourselves to be the victims of people who have much to gain financially from these fears.