Beyond blood pressure: new paradigms in sodium intake reduction and health outcomes.

Since 1980, when inaugural national dietary guidance was to "avoid too much sodium," recommendations have evolved to the 2010 Dietary Guidelines for Americans' quantified guidance of 2300 and 1500 mg/d [USDA and U.S. Department of Health and Human Services. Dietary guidelines for Americans, 1st (http://www.cnpp.usda.gov/DGAs1980Guidelines.htm) and 7th (http://www.health.gov/dietaryguidelines/dga2010/dietaryguidelines2010.pdf) eds.]. Too much sodium remains a valid concern, but are current targets too low for optimal health? New research moves beyond sodium's effect on the surrogate marker of blood pressure to examine the relation between sodium intake and cardiovascular morbidity and mortality. Results show that sodium intakes both less than and greater than ∼3000­5000 mg/d increase the risk of negative health outcomes. Additionally, newly compiled sodium intake data across populations show a uniformity that suggests that intake is physiologically set. Perhaps not coincidentally, the observed intakes fall within the range related to lowest risk. These findings are highly relevant to current efforts to achieve low sodium intakes across populations, because the data suggest that the efforts will be unsuccessful for healthy people and may cause harm to vulnerable populations. Remaining mindful of risks associated with both excessive and inadequate intakes is imperative with all nutrients, and sodium is no exception. Avoiding too much, and too little, sodium may be the best advice for Americans.

Popcorn is more satiating than potato chips in normal-weight adults.

BACKGROUND: Strategies that may increase compliance to reduced energy intakes are needed to reduce the health burden of obesity. Conflicting evidence exists regarding the effects of snacking on satiety and energy intake. METHODS: This study compared short-term satiety from two common snack foods, low fat popcorn or potato chips. Using a counterbalanced within-subject design, 35 normal weight non-smoking participants (17 men, 18 women) ages 20-50 years (mean age 33 ± 11, BMI 23 ± 2 kg/m²) consumed four conditions each: 200 mL of water (control), one cup (4 g, 15 kcal) popcorn, 6 cups (27 g, 100 kcal) popcorn, and one cup (28 g, 150 kcal) potato chips, each with 200 mL water. Participants rated their hunger, satisfaction, prospective consumption, and thirst on 100 mm visual analogue scales 30 minutes after commencement of snack consumption. In addition, post-snack energy intake from an ad libitum meal (amount served less amount remaining) was measured, and the test food and meal combined energy intake and energy compensation were calculated. RESULTS: Participants expressed less hunger, more satisfaction, and lower estimates of prospective food consumption after six cups of popcorn compared to all other treatments (P < 0.05). Energy compensation was 220% ± 967%, 76% ± 143% and 42% ± 75% after one cup popcorn, six cups popcorn and one cup potato chips, respectively. Combined energy intake was significantly greater (P < 0.01) during the potato chips condition (803 ± 277 kcal) compared to control (716 ± 279 kcal) or popcorn conditions (698 ± 286 kcal for one cup and 739 ± 294 kcal for six cups). Combined energy intakes from both popcorn conditions were not significantly different than control (p > 0.05). CONCLUSION: Popcorn exerted a stronger effect on short-term satiety than did potato chips as measured by subjective ratings and energy intake at a subsequent meal. This, combined with its relatively low calorie load, suggests that whole grain popcorn is a prudent choice for those wanting to reduce feelings of hunger while managing energy intake and ultimately, body weight.

Potential health benefits and medical cost savings from calorie, sodium, and saturated fat reductions in the American diet.

PURPOSE: Model the potential national health benefits and medical savings from reduced daily intake of calories, sodium, and saturated fat among the U.S. adult population. DESIGN: Simulation based on secondary data analysis; quantitative research. Measures include the prevalence of overweight/obesity, uncontrolled hypertension, elevated cholesterol, and related chronic conditions under various hypothetical dietary changes. SETTING: United States. SUBJECTS: Two hundred twenty-four million adults. MEASURES: Findings come from a Nutrition Impact Model that combines information from national surveys, peer-reviewed studies, and government reports. ANALYSIS: The simulation model predicts disease prevalence and medical expenditures under hypothetical dietary change scenarios. RESULTS: We estimate that permanent 100-kcal reductions in daily intake would eliminate approximately 71.2 million cases of overweight/obesity and save $58 billion annually. Long-term sodium intake reductions of 400 mg/d in those with uncontrolled hypertension would eliminate about 1.5 million cases, saving $2.3 billion annually. Decreasing 5 g/d of saturated fat intake in those with elevated cholesterol would eliminate 3.9 million cases, saving $2.0 billion annually. CONCLUSIONS: Modest to aggressive changes in diet can improve health and reduce annual national medical expenditures by $60 billion to $120 billion. One use of the model is to estimate the impact of dietary change related to setting public health priorities for dietary guidance. The findings here argue that emphasis on reduction in caloric intake should be the highest priority.

Predicted national productivity implications of calorie and sodium reductions in the American diet.

PURPOSE: To model the potential long-term national productivity benefits from reduced daily intake of calories and sodium. DESIGN: Simulation based on secondary data analysis; quantitative research. Measures include absenteeism, presenteeism, disability, and premature mortality under various hypothetical dietary changes. SETTING: United States. SUBJECTS: Two hundred twenty-five million adults. MEASURES: Findings come from a Nutrition Impact Model that combines information from national surveys, peer-reviewed studies, and government reports. ANALYSIS: We compare current estimates of national productivity loss associated with overweight, obesity, and hypertension to estimates for hypothetical scenarios in which national prevalence of these risk factors is lower. Using the simulation model, we illustrate how modest dietary change can achieve lower national prevalence of excess weight and hypertension. RESULTS: We estimate that permanent 100-kcal reductions in daily intake among the overweight/obese would eliminate approximately 71.2 million cases of overweight/obesity. In the long term, this could increase national productivity by $45.7 billion annually. Long-term sodium reductions of 400 mg in those with uncontrolled hypertension would eliminate about 1.5 million cases, potentially increasing productivity by $2.5 billion annually. More aggressive diet changes of 500 kcal and 1100 mg of sodium reductions yield potential productivity benefits of $133.3 and $5.8 billion, respectively. CONCLUSIONS: The potential long-term benefit of reduced calories and sodium, combining medical cost savings with productivity increases, ranges from $108.5 billion for moderate reductions to $255.6 billion for aggressive reductions. These findings help inform public health policy and the business case for improving diet. (AmJ Health Promot 2009;23[6]:423-430.)

Popcorn consumption and dietary and physiological parameters of US children and adults: analysis of the National Health and Nutrition Examination Survey (NHANES) 1999-2002 dietary survey data.

Popcorn is a whole-grain food/snack that is included among foods recommended in the 2005 Dietary Guidelines for Americans and MyPyramid to increase whole-grain consumption. The purpose of the present study was to use 1999-2002 National Health and Nutrition Examination Survey 24-hour dietary recall data to determine the average popcorn intake among Americans, and whether popcorn consumers exhibited different dietary intake patterns or physiological biomarkers of cardiovascular disease compared with popcorn non-consumers. Mean intake among consumers of popcorn was 38.8 g/day. Compared with non-consumers, popcorn consumers had approximately 250% higher (P<0.01) intake of whole grains (2.5 vs 0.70 servings/day) and approximately 22% higher (P<0.01) intake of fiber (18.1 vs 14.9 g/day). Small but significant differences (P<0.01) were also observed for intake of carbohydrate, magnesium (higher intake in popcorn consumers), protein, niacin, and folate (lower intake in popcorn consumers). In addition, popcorn consumers had a greater (P<0.01) intake of total grains and consumed fewer meat servings. Popcorn consumption was associated with increased intake of whole grains, dietary fiber, and certain other nutrients.

Hydration: issues for the 21st century.

Historically, hydration research reflected critical issues of the day. War, illness, surviving a shipwreck or time in the dessert, supplying fall-out shelters, and space exploration drove hydration research in the first half of the 20th century. The fitness revolution of the 1970s spurred research on dehydration in physically active people and athletes. The 1990s introduced the "fluid/disease relationship." What will be the driving force behind hydration research in the 21st century? Where are the gaps in our knowledge? This review provides an overview of issues pertinent to determining future directions in hydration research.

The effect on hydration of two diets, one with and one without plain water.

OBJECTIVE: To measure the effect on hydration of two regimens, one that included drinking water as part of the dietary beverages and one that did not. METHODS: In healthy, sedentary subjects, two different diets were evaluated for their effect on hydration. Trial A provided plain water to drink as part of the beverages served. Trial B omitted plain water from the beverages served. Twenty-seven males, during two three-day confinement periods, consumed one of two diets in a random, crossover and counterbalanced fashion, while diet, physical activity and environment were controlled and monitored. Body weight and 24-hour urine volumes were measured. Pre- and post-trial urine samples and 24-hour urines were assayed for osmolality, specific gravity, chloride, sodium and potassium, and sodium/potassium ratio was calculated. Twenty-four hour creatinine levels were determined. RESULTS: No differences (p > 0.05) were found between trials for body weight or other indicators of hydration status measured. CONCLUSIONS: Inclusion of plain drinking water compared to exclusion of plain drinking water in the diet did not affect the markers of hydration used in this study.