Editorial: Nutrition Research Reviews

With world attention now focusing on the Olympics, the question as to the extent to which nutrient intakes can affect athletic performance is highly topical; in this context, the articl

Editorial: Nutrition Research Reviews

The diverse nature of the reviews included in this issue of Nutrition Research Reviews highlights a problem that is becoming increasingly acute for journal editors, namely that of finding suitable reviewers (especially for the more esoteric manuscripts) who are prepared to devote some of their time and expertise to this crucial task. Peer-review underpins the whole ethos of scientific journal publishing as we currently know it. Without it, readers have little guarantee that the published material is credible, which in turn casts the authors in a dubious light, and with them the editors and publishers of the journals; the whole publishing endeavour is then in danger of losing objectivity and hence value (both academic and financial). There is of course increasing pressure on researchers to publish (now even more acute in the current economic climate if they are to attract ever-scarcer funding) which has led to increasing article submission rates to the reputable journals, and an increased headache for their editors who find themselves sending out more and more requests to potential reviewers who seem less and less able to say ‘yes’. The law of diminishing returns has definitely set in, but it hardly needs to be said that because the reviewers are themselves authors, they will inevitably suffer themselves from the lack of peerreview. Thus would-be authors are advised to contemplate the fact that if they do not feed into the system at both points, that is as authors and reviewers, the scope for publishing in a career-enhancing manner (i.e. in a reputable peer-reviewed journal) will ultimately dry up

Editorial: Nutrition Research Reviews

We are all familiar with the dietary guideline exhorting us to eat so many portions of oily fish per week in order to boost our intakes of n-3 long-chain PUFA, but it is perhaps not so widely realised that the fish must themselves be provided with dietary n-3 long-chain PUFA or, possibly, their precursors (though, as in humans, the ability of carnivorous fish to elongate and desaturate n-3 PUFA appears to be limited)

Editorial: Nutrition Research Reviews

Cognitive performance in children and whether this can be improved by nutritional means is an area of investigation fraught with experimental challenges, making it difficult to draw useful conclusions. Hoyland et al. (1) have here provided a much-needed systematic review of the evidence on the specific question of the effects of breakfast on children’s cognitive performance and, unsurprisingly, have concluded that the effects are generally positive, most clearly shown for memory and attention tasks and most easily demonstrated in nutritionally vulnerable children. However, the benefits of food before schoolwork are not necessarily purely, or even mostly, physiological; they could be due to some other factors associated with the meal provision, such as improved motivation to learn due to the reduction of hunger, or better attendance when the breakfast is provided at school

Editorial: Nutrition Research Reviews

This is the time of year when pumpkins are in season, and are incorporated into traditional festivals in Europe and North America (Harvest, Halloween, Thanksgiving). If you have previously considered pumpkins as good only for carving into grinning Jack O’Lanterns then the short review from Yadev et al. (1) might shed a little light on some of its potential medicinal properties, including antioxidant, antiinflammatory, anti-carcinogenic and anti-diabetic. However, the active compounds, possibly various alkaloids and flavonoids, have yet to be isolated and characterised, and much of the work cited has been done in animal or in vitro models, so the beneficial effects need to be confirmed in human subjects before pumpkin can graduate from traditional herbal remedy to new, safe, effective therapeutic agent. Pumpkin, along with its fruit and vegetable colleagues, has been linked with reduced risk of oesophageal adenocarcinoma and its precursor, Barratt’s oesophagus; this relationship is explored by Kubo et al. in their review(2). The epidemiological evidence is apparently strongest for a protective effect of vitamin C, b-carotene, raw fruit and dark green, leafy and cruciferous vegetables, carbohydrates, fibre, Fe and possibly folate, while red meat and processed foods are associated with increased risk. Red and processed meats have long been dietary suspects in breast cancer carcinogenesis, though the evidence has been controversial, prompting Alexander et al. to conduct a review and meta-analysis(3) of all available prospective cohort studies, incorporating over 25 000 cases of breast cancer. The consensus the authors arrive at is that there is no strong independent association between intake of red meat or processed meat and breast cancer, though they note that results were sensitive to the choice of model (fixed or random effects). Hypotheses concerning the possible role of diet early in life need further (very long-term!) prospective studies, while investigation of the (conflicting) evidence from studies suggesting that meat intake could affect cancer risk through tumour hormone receptor status, whether positive or negative, is also required before unequivocal conclusions can be drawn

Editorial: Nutrition Research Reviews

The diverse nature of the reviews included in this issue of Nutrition Research Reviews highlights a problem that is becoming increasingly acute for journal editors, namely that of finding suitable reviewers (especially for the more esoteric manuscripts) who are prepared to devote some of their time and expertise to this crucial task. Peer-review underpins the whole ethos of scientific journal publishing as we currently know it. Without it, readers have little guarantee that the published material is credible, which in turn casts the authors in a dubious light, and with them the editors and publishers of the journals; the whole publishing endeavour is then in danger of losing objectivity and hence value (both academic and financial). There is of course increasing pressure on researchers to publish (now even more acute in the current economic climate if they are to attract ever-scarcer funding) which has led to increasing article submission rates to the reputable journals, and an increased headache for their editors who find themselves sending out more and more requests to potential reviewers who seem less and less able to say ‘yes’. The law of diminishing returns has definitely set in, but it hardly needs to be said that because the reviewers are themselves authors, they will inevitably suffer themselves from the lack of peerreview. Thus would-be authors are advised to contemplate the fact that if they do not feed into the system at both points, that is as authors and reviewers, the scope for publishing in a career-enhancing manner (i.e. in a reputable peer-reviewed journal) will ultimately dry up

Editorial: Nutrition Research Reviews

Cognitive performance in children and whether this can be improved by nutritional means is an area of investigation fraught with experimental challenges, making it difficult to draw useful conclusions. Hoyland et al. (1) have here provided a much-needed systematic review of the evidence on the specific question of the effects of breakfast on children’s cognitive performance and, unsurprisingly, have concluded that the effects are generally positive, most clearly shown for memory and attention tasks and most easily demonstrated in nutritionally vulnerable children. However, the benefits of food before schoolwork are not necessarily purely, or even mostly, physiological; they could be due to some other factors associated with the meal provision, such as improved motivation to learn due to the reduction of hunger, or better attendance when the breakfast is provided at school

The Effect of Dietary Supplements of w3 Polyunsaturated Fatty Acids on the Fatty Acid Composition of Platelets and Plasma Choline Phosphoglycerides

Although it is not known iflinolenic acid (18:3w3) is essential its derivatives are important (Tinoco et a/. 1979). Eicosapentaenoic acid (20:5w3) is the precursor of the triene prostaglandins (Gryglewski et a/. 1979) and when incorporated into platelet lipids may influence bleeding time (Sanders et al. 1980). Docosahexaenoic acid (22:0013) is a major component of human brain and retinal lipids and is found in its highest concentrations in the phosphoglycerides of synaptic membranes and rod outer segments implying that it has a role in neural transmission. Radiotracer experiments in vitro suggest that man can convert 18:3w3 to 20:5w3 and 22:0013 (De Gomez Dumm & Brenner, 1975; Aerberhard et al. 1978) but this capacity may be limited (Dyerberg et a/. 1980). Consequently dietary 20: 5w3 and 22: 0013 may be important (Crawford & Sinclair, 1972), the only significant sources being fish, fish oil and offal (Shepherd et al. 1978; Southgate & Paul, 1978). Indeed, vegans whose diets are devoid of 20:5w3 and 22:0013 have very much lower proportions of these fatty acids in their plasma choline phosphoglycerides than do omnivores (Sanders eta/. 1977). It was suggested that the high value for the ratio, 18:2w6:18:3w3 in the vegan diets suppressed the transformation of 18:3w3 to 20: 5w3 and 22:6w3 and instead favoured the conversion of 18:2w6 to 20:4w6 and 22:4w6. This being so then a dietary supplement of 18: 3w3 should reduce the value for 18:2w6:18:3w3 and lead to an increase in the proportions of 20:5w3 and 22:0013 in this lipid fraction. In order to test this hypothesis, vegan and omnivore subjects were given a supplement of linseed oil, rich in 18:3w3 for 2 weeks and changes in their blood lipids were monitored. So that a comparison could be made between dietary linolenate and its long-chain derivatives, the effect of a fish oil supplement, rich in 20:5w3 and 22: 0013, was also studied in the omnivores

Socio-Economic Differences in Food Group and Nutrient Intakes Among Young Women in Ireland

The present study aimed to investigate socio-economic disparities in food and nutrient intakes among young Irish women. A total of 221 disadvantaged and seventy-four non-disadvantaged women aged 18–35 years were recruited. Diet was assessed using a diet history protocol. Of the total population, 153 disadvantaged and sixty-three non-disadvantaged women were classified as plausible dietary reporters. Food group intakes, nutrient intakes and dietary vitamin and mineral concentrations per MJ of energy consumed were compared between the disadvantaged and non-disadvantaged populations, as was compliance with dietary fibre, macronutrient and micronutrient intake guidelines. The disadvantaged women had lower intakes than the non-disadvantaged women of fruit, vegetables, fish, breakfast cereals, low-fat milk and wholemeal bread (all P,0·001), yogurt (P¼0·001), low-fat spread (P¼0·002) and fresh meat (P¼0·003). They also had higher intakes of butter, processed red meats, white bread, sugar-sweetened beverages, fried potatoes and potato-based snacks (all P,0·001) and full-fat milk (P¼0·014). Nutritionally, the disadvantaged women had higher fat, saturated fat and refined sugar intakes; lower dietary fibre, vitamin and mineral intakes; and lower dietary vitamin and mineral densities per MJ than their more advantaged peers. Non-achievement of carbohydrate (P¼0·017), fat (P,0·001), saturated fat (P,0·001), refined sugar (P,0·001), folate (P¼0·050), vitamin C (P,0·001), vitamin D (P¼0·047) and Ca (P¼0·019) recommendations was more prevalent among the disadvantaged women. Both groups showed poor compliance with Fe and Na guidelines. We conclude that the nutritional deficits present among these socially disadvantaged women are significant, but may be potentially ameliorated by targeted food-based interventions