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Alison Paul BSc (Nutrition) and D. A. T. Southgate PhD discuss the limitations and use of food composition tables. This is the second of two articles to mark the publication of the fourth revised edition of McCance and Widdowson's The Composition of Food.

Food composition tables are an essential tool for anyone wishing to calculate the nutrient content of a diet, whether for use in therapeutic dietetics or in nutritional surveys both at the national and research level. They also provide much of the information on which the teaching of the nutritional values of foods is based.

While the scientific reaction to many of the claims made for the benefits of dietary fibre is ‘it's too good to be true’, there is wide acceptance by the general public and the media that an increased intake of dietary fibre is a good thing. There is, however, still confusion about what dietary fibre is and how much there is in foods and the diet. In this, the first of two articles, Professor D.A.T. Southgate and Richard Faulks, of the AFRC Institute of Food Research, Norwich attempt to answer the basic question, what is dietary fibre?

There is considerable epidemiological and direct experimental evidence concerning the nutritional benefits of dietary fibre. Over the last few years, and particularly as a result of the publication of The F‐Plan Diet, public awareness and interest in this topic has increased enormously in the UK and there has been a growing demand both for information about the dietary fibre content of foods and for food products containing higher levels of dietary fibre. It is becoming increasingly important, therefore, to understand exactly what is meant by the term ‘dietary fibre’. In this article Helen F. Kearns, BSc and Gillian D.A. Lowy, MA, review the methods that are used for the determination of fibre in foodstuffs, outline some of the physiological effects of dietary fibre, and discuss how values quoted for the dietary fibre contents of foods may be interpreted in the light of their physiological role.

Translating the conceptual basis of dietary fibre into a definition that can be used as the basis for practicable analytical methods has been a matter for considerable debate amongst those involved in dietary fibre measurements. The original authors used the term “dietary fibre” for the plant cell wall material in foods and this provides the most satisfactory starting point in any discussion on analysis. Compares the two most widely used approaches for the measurement of dietary fibre and considers their bases in relation to the conceptual origin of dietary fibre as a protective factor in the diet.

Imagine Sir Edmund Hillary and Tenzing Norkey arriving at the summit of Everest (29,029 ft) in 1953, only to discover that they were standing on several thousand feet of ice. Imagine the questions that would have followed. Had they climbed the wrong mountain? Could they still legitimately claim to be standing at the highest point on the Earth's surface? How should the heights of mountains be recorded for official purposes?

The next month or two behind us and this decade will have passed, to merge in the drab background of the post‐war years, part of the pattern of frustration, failure and fear. The ‘swinging sixties’ some called it, but to an older and perhaps slightly jaundiced eye, the only swinging seemed to be from one crisis to another, like the monkey swinging from bough to bough in his home among the trees; the ‘swingers’ among men also have their heads in the clouds! In the seemingly endless struggle against inflation since the end of the War, it would be futile to fail to see that the country is in retreat all the time. One can almost hear that shaft of MacLeodian wit christening the approaching decade as the ‘sinking seventies’, but it may not be as bad as all that, and certainly not if the innate good sense and political soundness of the British gives them insight into their perilous plight.

One of the major developments of the post‐War years has been the rise of consumer protection ‘watchdog’ committees galore, a flood of legislation and completely changed enforcement methods by existing local authority officers who to all and intents have become a completely new service. Voluntary agencies, national and local, based on the local High Street, have appointed themselves the watchdogs of the retail trade; legislation and central departments, the larger scene. The new service has proved of inestimable value in the changed conditions; it continues to develop. When shopping was a personal transaction, with the housewife making her purchases from the shopkeeper or his staff on the opposite side of the counter; when each was well known to the other and the relationship had usually lasted for many years, often from one generation to the next, things were very different, complaints few, unsatisfactory items instantly replaced, usually without question. This continuing state of equanimity was destroyed by the retail revolution and new methods of advertising and marketing. Now, the numbers of complaints dealt with by consumer protection and environmental health departments of local authorities are truly enormous. We have become a nation of “complainers,” although in all conscience, we have much to complain about. Complaints cover the widest possible range of products and services, of which food and drink form an integral component. The complaints to enforcement authorities include many said to be unjustified, but from the reports of legal proceedings under relevant enactments, it is obvious that the bulk of them now originate from consumer complaints. Not all complainants, however, relish the thought of the case going before the courts. Less is heard publicly of complaints to the numerous voluntary bodies. Enforcement authorities see complaints in terms of infringements of the law, although their role as honest broker, securing recompense to the aggreived customer, has become important; a few departments being able to claim that they secured reimbursements and replacements of value totalling upwards of amounts which annually run into six figures. The broker role is also that adopted by voluntary bodies but with much less success since they lack the supporting authority of legal sanction.

In the last article we saw how Goldberger, in 1926, demonstrated that the ‘Water soluble B’ factor of McCollum and Davies contained more than one vitamin. He showed that pellagra was associated with the lack of a vitamin and that the latter was distributed in a somewhat similar manner to the anti‐beri‐beri factor. However, Goldberger demonstrated that there was an essential difference between the two factors: the one preventing pellagra was more stable to heat. He called it the pellagra‐preventive, or P‐P factor.

It is widely recognised that there is a significant gap in our knowledge on the nutritional content of meals provided by the catering industry. The annual National Household Food Consumption and Expenditure Survey,1 provides information on household food purchases, which is used to estimate the nutritional intake of individuals. It does not provide any nutritional information on meals purchased and consumed outside the home.