Dietary sources of sodium across the diverse New Zealand adult population.

Our aim was to determine dietary sources of sodium for adults in Aotearoa New Zealand (NZ). We used data from the most recent NZ Adult Nutrition Survey (ANS 2008/09) including 4,721 free-living adults aged 15+ years who completed a single 24-hour dietary recall. Population weighted percentage contribution to dietary sodium was calculated and ranked for major and minor food categories across the total population and by gender (male and female), ethnicity (Maori, Pacific, Asian, and Other), and age (15 to 20, 21 to 40, 41 to 60, and 61+ years). Fifteen major food categories contributed ∼80% of sodium consumed by the total population; the top five were 'Bread' (18%), 'Bread-based dishes' (11%), 'Grains and pasta' (7%), 'Pork' (7%), and 'Sausages and processed meats' (5%). Compared to other sub-groups within the same demographic, the top-five major sources of sodium specific to Females were 'Soups and stocks', Pacific communities were Poultry, Maori whanau was 'Pork', Others was 'Pork', Asian was 'Soups and stocks' and 'Vegetables', and 61+ years was 'Soups and stocks'. Our findings provide information on the major and minor food sources of sodium for the diverse NZ population. The differences observed in major dietary sources by population subgroup are critical for policymakers to include in the development of any future country-specific sodium reduction targets; repeating the total population approach taken in several other countries is unlikely to improve inquities in heart-related health in NZ.

Plasma and erythrocyte fatty acids reflect intakes of saturated and n-6 PUFA within a similar time frame.

Erythrocytes, compared with plasma, are considered more robust markers of n-3 (ω-3) polyunsaturated fatty acid (PUFA) intake, because dietary-induced change in fatty acid (FA) composition takes longer to complete. The extent to which this applies to intakes of saturated fatty acid (SFA) or n-6 PUFA is unclear. We compared the pattern of change over time in the fatty acid composition of plasma, erythrocyte, buccal cell, and adipose tissue lipids when changing between diets high in SFA or n-6 PUFA. Twenty-four (n = 7 male) healthy participants were instructed to consume either an SFA-rich (18% energy) or n-6 PUFA-rich (10% energy) diet for 8 wk before crossing over, without washout, to the alternate diet. The FA composition of plasma triacylglycerol (TG), nonesterified FAs, cholesterol ester, total phospholipids, erythrocyte total phospholipids, erythrocyte phosphatidylcholine, and buccal cell total phospholipids was measured every 2 wk and adipose tissue TG every 4 wk during the 16-wk intervention. Linoleic acid composition of plasma, erythrocyte, and buccal cell lipids increased (P < 0.01) during the first 2 wk of the n-6 PUFA diet and remained unchanged during the remaining 6 wk. During the 8-wk SFA diet, the same pattern of change over time occurred for the pentadecanoic acid composition of plasma and erythrocyte lipids; however, the pentadecanoic acid composition of buccal cell lipids did not differ between the diet periods. There were no differences in linoleic or pentadecanoic acid composition of adipose tissue TG. These results suggest plasma and erythrocyte FAs reflect intakes of SFA and n-6 PUFA over a similar period of time.

Do effects of price discounts and nutrition education on food purchases vary by ethnicity, income and education? Results from a randomised, controlled trial.

BACKGROUND: Reducing health inequalities requires interventions that work as well, if not better, among disadvantaged populations. The aim of this study was to determine if the effects of price discounts and tailored nutrition education on supermarket food purchases (percentage energy from saturated fat and healthy foods purchased) vary by ethnicity, household income and education. METHOD: A 2×2 factorial trial of 1104 New Zealand shoppers randomised to receive a 12.5% discount on healthier foods and/or tailored nutrition education (or no intervention) for 6 months. RESULTS: There was no overall association of price discounts or nutrition education with percentage energy from saturated fat, or nutrition education with healthy food purchasing. There was an association of price discounts with healthy food purchasing (0.79 kg/week increase; 95% CI 0.43 to 1.16) that varied by ethnicity (p=0.04): European/other 1.02 kg/week (n=755; 95% CI 0.60 to 1.43); Pacific 1.20 kg/week (n=101; 95% CI 0.06 to 2.34); Maori -0.15 kg/week (n=248; 95% CI -1.10 to 0.80). This association of price discounts with healthy food purchasing did not vary by household income or education. CONCLUSIONS: While a statistically significant variation by ethnicity in the effect of price discounts on food purchasing was found, the authors caution against a causal interpretation due to likely biases (eg, attrition) that differentially affected Maori and Pacific people. The study highlights the challenges in generating valid evidence by social groups for public health interventions. The null findings for tailored nutritional education across all social groups suggest that structural interventions (such as price) may be more effective.

Effects of price discounts and tailored nutrition education on supermarket purchases: a randomized controlled trial.

BACKGROUND: Traditional methods to improve population diets have largely relied on individual responsibility, but there is growing interest in structural interventions such as pricing policies. OBJECTIVE: The aim was to evaluate the effect of price discounts and tailored nutrition education on supermarket food and nutrient purchases. DESIGN: A 2 x 2 factorial randomized controlled trial was conducted in 8 New Zealand supermarkets. A total of 1104 shoppers were randomly assigned to 1 of the following 4 interventions that were delivered over 6 mo: price discounts (12.5%) on healthier foods, tailored nutrition education, discounts plus education, or control (no intervention). The primary outcome was change in saturated fat purchased at 6 mo. Secondary outcomes were changes in other nutrients and foods purchased at 6 and 12 mo. Outcomes were assessed by using electronic scanner sales data. RESULTS: At 6 mo, the difference in saturated fat purchased for price discounts on healthier foods compared with that purchased for no discount on healthier foods was -0.02% (95% CI: -0.40%, 0.36%; P = 0.91). The corresponding difference for tailored nutrition education compared with that for no education was -0.09% (95% CI: -0.47%, 0.30%; P = 0.66). However, those subjects who were randomly assigned to receive price discounts bought significantly more predefined healthier foods at 6 mo (11% more; mean difference: 0.79 kg/wk; 95% CI: 0.43, 1.16; P < 0.001) and 12 mo (5% more; mean difference: 0.38 kg/wk; 95% CI: 0.01, 0.76; P = 0.045). Education had no effect on food purchases. CONCLUSIONS: Neither price discounts nor tailored nutrition education had a significant effect on nutrients purchased. However, the significant and sustained effect of discounts on food purchases suggests that pricing strategies hold promise as a means to improve population diets.

Does tailoring make a difference? A systematic review of the long-term effectiveness of tailored nutrition education for adults.

Tailoring individualizes information to the receiver and provides a potential strategy for improving dietary intakes. The present systematic review summarizes evidence for the long-term (> or =6 months) effectiveness of tailored nutrition education for adults and includes priority population groups. Key electronic databases and relevant bibliographies were searched for trials measuring the following outcomes: nutrition-related health behaviors (e.g., dietary intake and food purchases) and anthropometric measures. Data synthesis was comprised of meta-analysis (for 15 trials including all population groups) and narrative review (for five trials of priority population groups). Overall, the quality of the studies was moderate to good. Tailored nutrition education was found to be a promising strategy for improving the diets of adults (including those in priority population groups) over the long term. However, future studies should ensure adequate reporting of research design and methods and reduce the chances of false-positive findings by using more objective measures of diet, clearly identifying the primary study outcome, and concentrating on outcomes most relevant to nutrition-related disease.