Of interest from the journals.

Trans fatty acids

Jakobsen MU, Bysted A, Andersen NL et al. Intake of ruminant trans fatty acids in the Danish population aged 1-80 yrs. Eur J Cin Nutr 2006; 60: 312-18.

This study based on seven-day food records from a gender and age stratified random sample of 3098 participants drawn from the Danish Civil Registration System found the median intake of ruminant trans fatty acids ranged from 1.4 g/day for children aged one to six years to 1.8 g/day among adults aged 30-80 years. Dairy products were the main source. This study would enable an evaluation of associations between ruminant TFA intakes and risk of coronary heart disease.

Functional foods

Hongisto S-M, Paajanen L, Saxelin M, Korpela R. A combination of fibre-rich rye bread and yoghurt containing Lactobaccilus GG improves bowel function in women with self-reported constipation. Eur J Cin Nutr 2006; 60: 319-24.

This experimental study used a two by two factorial design with 59 free living women recruited by advertisement with self-reported constipation. The diet groups were given rye bread + LGG yoghurt, rye bread alone, LGG yoghurt alone or control (low-fibre toast, no LGG) for three weeks followed by three weeks follow up. Outcome measures were transit time, recorded faecal frequency and consistency, difficulty in defecation and gastrointestinal symptoms. Compared with the control, rye bread produced significantly improved outcomes for constipation but with increased gastrointestinal symptoms (P < 0.001), which were attenuated when consumed with GG yoghurt.

Doornbos AME, Meynen EM, Duchateau GSMJE, van der Knaap HCM, Trautwein EA. Intake occasion affects the serum cholesterol lowering of a plant sterol-enriched single-dose yoghurt drink in mildly hypercholesterolemic subjects. Eur J Cin Nutr 2006; 60: 325-33.

This randomised double-blind placebo-controlled parallel trial tested the efficacy of a single 100g yoghurt drink containing plant sterol esters, taken either with or without a meal, in mildly hypercholesterolemic (LDL ~4.0 mmol/L) volunteers. Optimal cholesterol-lowering efficacy was established when the product was taken with a meal.

Blom WAM, Lluch A, Stafleu A et al. Effect of a high protein breakfast on the post prandial ghrelin response. Am J Clin Nutr 2006; 83: 211-20.

Ghrelin is secreted by the stomach and appears to produce a hunger signal. This experimental study of 15 healthy men in a single-blind crossover meal test compared a high-protein versus a high-carbohydrate isocaloric breakfast with subjective satiety and blood sample measurements taken for the next three hours. The high-protein breakfast resulted in significantly reduced ghrelin secretion compared with the high-carbohydrate breakfast (P <0.01), which might explain one of the apparent satiating effects of higher-protein meals.

Obesity and food consumption

Andrieu E, Darmon N, Drewnowski A. Low-cost diets: more energy, fewer nutrients. Eur J Cin Nutr 2006; 60: 434-6.

In this analysis of the 1998 French National Food Consumption Survey, data from adult participants were stratified by quartiles of energy cost ([euro]/10 MJ) to find that those in the lowest quartile of energy cost had the highest energy intakes and the lowest intake of key nutrients, and vice versa. These data supported the hypothesis that more nutrient dense diets are associated with higher costs.

Ovaskainen M-L, Reinivuo H, Tapanainen H, Hannila M-L, Korhonen T, Pakkala H. Snacks as an element of energy intake and food consumption. Eur J Cin Nutr 2006; 60: 494-501.

Snacks were defined as all eating events between break fast, lunch and dinner as reported in an interviewer-assisted 48-hour dietary recall applied in the national FINDIET 2002 survey of 2007 Finnish adults. Main meals comprised traditional mixed dishes, bread and milk, whereas snacks tended to comprise foods with a higher energy density (MJ/1.00 g). The snack-dominant meal pattern, found in 19% of men and 24% of women did not conform to nutrition recommendations because of high energy density and low nutritional value, but it was acknowledged that research was necessary to examine the effect on health status.

Whybrow S, Stephen JR, Stubbs RJ. The evaluation of an electronic visual analogue scale system for appetite and mood. Eur J Cin Nutr 2006; 60: 558-60.

This short communication reports on the validation of a new electronic appetite rating system (EARS) relative to that obtained by a traditional pen and paper report in 20 free living normal-weight adults. Subjective motivation to eat and mood were logged each hour while awake on randomised test days and consuming a fixed diet. The electronic system proved reliable, but there was significant bias between methods, suggesting that the two methods are not interchangeable.

Rolls BJ, Roe LS, Meengs JS. Larger portion sizes lead to a sustained increase in energy intake over 2 days. J Am Diet Assoc 2006; 106: 543-9.

This experimental randomised crossover study of 32 university-based adults found that increasing portion sizes of standard meals in a controlled setting increased energy intake in both men and women (P < 0.0001). As ratings of fullness did not differ significantly with increasing portion size, the authors commented that large portions could contribute to increased body weight.

Dietary methodology

Mahabir S, Baer DJ, Subar A et al. Calorie intake misreporting by diet record and food frequency questionnaire compared to doubly labelled water among postmenopausal women. Eur J Cin Nutr 2006; 60: 561-5. This validation study of baseline measurements in 65 healthy postmenopausal women found an average underestimation of reported energy intake (compared with doubly labelled water assessments of energy expenditure) by 37% using a seven-day diet record and by 42% using the food frequency questionnaire of the National Cancer Institute. The authors noted this has implications for the interpretations of findings of energy--disease association studies using these instruments.

IUNS lecture

Wahlquist ML. Towards a new generation of international nutrition science and scientist: the importance of Africa and its capacity. J Nutr 2006; 136: 1048-9. This is a highlight of the IUNS E V McCollum Award Lecture presented at the 18th International Congress of Nutrition in Durban, South Africa, September 2005. Wahlquist argues for innovative nutrition science to meet the challenges of the 21st century, based on partnerships within and beyond science, integrative as well as analytical perspectives, and the articulation of unifying mechanisms. He emphasised the position of Africa in this process, and how advances in government, science and technology can enable a better future for all.

Lactose intolerance

Savaiano DA, Boushey CJ, McCabe GP. Lactose intolerance symptoms assessed by meta-analysis: a grain of truth that leads to exaggeration. J Nutr 2006; 136: 1107-13.

This meta-analysis was conducted based on studies of lactose intolerance symptoms under conditions of lactose and placebo consumption. From 1553 citations, 21 studies with defined design features were analysed by two independent reviewers. The effect size for diarrhoea was found to be very small, and the authors concluded that lactose was not a major cause of symptoms following one cup of dairy foods.

Biomarkers

Crowe FL, Skeaff CM, Green TJ, Gray AR. Serum fatty acids as biomarkers of fat intake predict serum cholesterol concentrations in a population-based survey of New Zealand adolescents and adults. Am J Clin Nutr 2006; 83: 887-94.

This study analysed the measured fatty acid composition of serum cholesterol esters, phospholipids and triacylglycerols in conjunction with cross-sectional data from 2793 participants aged [greater than or equal to] 15 years from the 1997 New Zealand National Nutrition Survey. The authors concluded that biomarkers of reported saturated and polyunsaturated fat intakes were significant predictors of serum cholesterol concentrations in this population.

Nutrigenomics

Trujillo E, Davis C, Milner J. Nutrigenomics, proteonomics, metabolomics and the practice of dietetics. J Am Diet Assoc 2006; 106: 403-13.

This continuing education article with associated questionnaire outlines the definitions of the key terms related to this area of study and provides examples of nutrients and bioactives that can alter genetic and epigenetic events. It explains DNA methylation and describes microarray technologies that provide some of the necessary information for nutrigenomics practice. This is cutting-edge knowledge for tomorrow's dietitian.