Water, hydration, and health

The relationship of perceptions of tap water safety with intake of sugar-sweetened beverages and plain water among US adults

OBJECTIVE

Research is limited on whether mistrust of tap water discourages plain water intake and leads to a greater intake of sugar-sweetened beverages (SSB). The objective of the present study was to examine demographic differences in perceptions of tap water safety and determine if these perceptions are associated with intake of SSB and plain water.

DESIGN

The study examined perceptions of tap water safety and their cross-sectional association with intake of SSB and plain water. Racial/ethnic differences in the associations of tap water perceptions with SSB and plain water intake were also examined.

SETTING

Nationally weighted data from the 2010 HealthStyles Survey (n 4184).

SUBJECTS

US adults aged ≥18 years.

RESULTS

Overall, 13·0 % of participants disagreed that their local tap water was safe to drink and 26·4 % of participants agreed that bottled water was safer than tap water. Both mistrust of tap water safety and favouring bottled water differed by region, age, race/ethnicity, income and education. The associations of tap water mistrust with intake of SSB and plain water were modified by race/ethnicity (P < 0·05). Non-white racial/ethnic groups who disagreed that their local tap water was safe to drink were more likely to report low intake of plain water. The odds of consuming ≥1 SSB/d among Hispanics who mistrusted their local tap water was twice that of Hispanics who did not (OR = 2·0; 95 % CI 1·2, 3·3).

CONCLUSIONS

Public health efforts to promote healthy beverages should recognize the potential impact of tap water perceptions on water and SSB intake among minority populations.

Recommendations for healthier hydration: addressing the public health issues of obesity and type 2 diabetes

Given the rapid increase in the prevalence of overweight, obesity, type 2 diabetes and other obesity-related conditions across the world, despite a plethora of evidence-based guidance for clinicians, innovative campaigns aimed at the general public and widespread government public health initiatives, it is clear that a novel approach is required. The importance of fluid intake has been overlooked in campaigns and guidelines and also in the clinical setting, where the question 'what do you drink?' is often omitted. It is a significant oversight that food pyramids and healthy-eating plates across the world omit fluids from their graphics and advice. While guidelines include recommendations on changes in physical activity and diet, often little or no advice is offered on the importance of healthier hydration practices, neglecting to highlight the contribution of beverages high in sugar, alcohol or additives. An interdisciplinary group of experts in medicine, nutrition, physiology and public health discussed issues surrounding healthy-hydration practices in March 2010 in Paris to create a consensus statement on hydration and gain of body weight and provide recommendations.

Getting back on tap: the policy context and cost of ensuring access to low-cost drinking water in Massachusetts schools

BACKGROUND

Adequate water intake may have important health benefits for schoolchildren. Layers of federal, state, and local policy are relevant to provision of water within schools. Recently passed state and federal laws require free drinking-water access for students during mealtimes.

PURPOSE

To review Massachusetts local district wellness policies related to water access, provide estimates of costs for three water-provision strategies, and discuss implications for policy relevant to adequate drinking-water access.

METHODS

Legal research was conducted using the LexisNexis legal database and government websites. Local wellness policies were double-coded using existing research tools. Costs of three water-delivery options were estimated using a 10-year school-district perspective.

RESULTS

Prior to 2010, most Massachusetts public school district wellness policies (92%-94%) did not address access to free drinking water. Ten-year costs per school for providing water during mealtimes to students, including dispenser unit, installation, water testing, water, cups, and labor, range between $12,544 and $27,922 (depending on water-delivery option) assuming the average Massachusetts school enrollment. Water-provision strategies relying on tap water are more economical than bottled water in the long term.

CONCLUSIONS

Policy recommendations and cost considerations deserve attention at the local, state, and federal levels. Recommendations are discussed to ensure access to safe, free drinking water for all students.

Increasing water availability during afterschool snack: evidence, strategies, and partnerships from a group randomized trial

BACKGROUND

Providing drinking water to U.S. children during school meals is a recommended health promotion strategy and part of national nutrition policy. Urban school systems have struggled with providing drinking water to children, and little is known about how to ensure that water is served, particularly in afterschool settings.

PURPOSE

To assess the effectiveness of an intervention designed to promote water as the beverage of choice in afterschool programs.

DESIGN

The Out of School Nutrition and Physical Activity Initiative (OSNAP) used a community-based collaboration and low-cost strategies to provide water after school. A group RCT was used to evaluate the intervention. Data were collected in 2010-2011 and analyzed in 2011.

SETTING/PARTICIPANTS

Twenty afterschool programs in Boston were randomized to intervention or control (delayed intervention).

INTERVENTION

Intervention sites participated in learning collaboratives focused on policy and environmental changes to increase healthy eating, drinking, and physical activity opportunities during afterschool time (materials available at www.osnap.org). Collaboration between Boston Public Schools Food and Nutrition Services, afterschool staff, and researchers established water-delivery systems to ensure children were served water during snack time.

MAIN OUTCOME MEASURES

Average ounces of water served to children per day was recorded by direct observation at each program at baseline and 6-month follow-up over 5 consecutive school days. Secondary measures directly observed included ounces of other beverages served, other snack components, and water-delivery system.

RESULTS

Participation in the intervention was associated with an increased average volume of water served (+3.6 ounces/day; p=0.01) during snack. On average, the intervention led to a daily decrease of 60.9 kcals from beverages served during snack (p=0.03).

CONCLUSIONS

This study indicates the OSNAP intervention, including strategies to overcome structural barriers and collaboration with key actors, can increase offerings of water during afterschool snack. OSNAP appears to be an effective strategy to provide water in afterschool settings that can be helpful in implementing new U.S. Department of Agriculture guidelines regarding water availability during lunch and afterschool snack.

Plain-water intake and risk of type 2 diabetes in young and middle-aged women

BACKGROUND

The replacement of caloric beverages such as sugar-sweetened beverages (SSBs) and fruit juices with noncaloric beverages such as plain water has been recommended for diabetes prevention.

OBJECTIVE

We evaluated the relation of plain-water intake and the substitution of plain water for SSBs and fruit juices with incident type 2 diabetes (T2D) in US women.

DESIGN

We prospectively followed 82,902 women in the Nurses' Health Study II who were free of diabetes, cardiovascular disease, or cancer at baseline. Diet, including various beverages, was assessed by using validated food-frequency questionnaires and updated every 4 y. Incident T2D was confirmed by using a validated supplementary questionnaire. We used a 4-y lagged analysis to minimize reverse causation (ie, increased water consumption that was due to early stage of diabetes).

RESULTS

During 1,115,427 person-years of follow-up, we documented 2718 incident T2D cases. Plain-water intake was not associated with T2D risk in the multivariable-adjusted model that included age, BMI, diet, and lifestyle factors; RRs (95% CIs) across categories (<1, 1, 2-3, 4-5, and ≥6 cups/d) were 1.00, 0.93 (0.82, 1.05), 0.93 (0.83, 1.05), 1.09 (0.96, 1.24), and 1.06 (0.91, 1.23), respectively (P-trend = 0.15). We estimated that the replacement of 1 serving SSBs and fruit juices/d by 1 cup plain water/d was associated with 7% (3%, 11%) and 8% (2%, 13%) lower risk of T2D, respectively.

CONCLUSIONS

Plain-water intake, per se, was not significantly associated with risk of T2D. However, substitution of plain water for SSBs or fruit juices was estimated to be associated with modestly lower risk of T2D.

Water and sugar-sweetened beverage consumption and changes in BMI among Brazilian fourth graders after 1-year follow-up

Objective

We examined whether drinking water per se is associated with drinking less of other beverages and whether changes in BMI are associated with the intake of water and other beverages.

Design

Secondary analysis of a randomized trial of fourth graders followed over 1 year.

Setting

Public schools in the metropolitan area of Rio de Janeiro, Brazil.

Subjects

Participants were 1134 students aged 10–11 years.

Results

At baseline, a higher frequency of water consumption was associated with a greater daily intake of fruit juice (P = 0·02) and a higher daily frequency of milk (P = 0·005). In the intervention group, the baseline frequency of water consumption was negatively associated with weight change over 1 year but without statistical significance (coefficient = −0·08 kg/m2; 95 % CI −0·37, 0·24 kg/m2), whereas fruit juice intake frequency was positively associated with weight change: each increase in fruit juice intake of 1 glass/d was associated with a BMI increase of 0·16 (95 % CI 0·02, 0·30) kg/m2.

Conclusions

Our findings do not support a protective effect of water consumption on BMI, but confirm consumption of juice drinks as a risk factor for BMI gain. Students who reported high water consumption also reported high intake of other beverages; therefore, the promotion of water consumption per se would not prevent excessive weight gain.

Reexamination of total fluid intake and bladder cancer in the Health Professionals Follow-up Study Cohort

It has been hypothesized that high fluid intake may reduce contact time between carcinogens and bladder epithelium and consequently reduce carcinogenesis. Epidemiologic studies examining fluid intake and bladder cancer have been extremely inconsistent, ranging from strong inverse to strong positive associations. The authors reevaluated the association between fluid intake and bladder cancer among 47,909 participants in the prospective Health Professionals Follow-up Study over a period of 22 years. During follow-up (1986-2008), 823 incident bladder cancer cases were diagnosed. Information on fluid intake was collected by using the food frequency questionnaire at baseline and every 4 years thereafter. Cox proportional hazard regression analysis was used to adjust for risk factors for bladder cancer. Total fluid intake was inversely associated with bladder cancer when the analysis was based on the baseline diet (relative risk = 0.76, 95% confidence interval: 0.60, 0.97), comparing the highest total daily fluid intake quintile (>2,531 mL/day) with the lowest quintile (<1,290 mL/day) (P(trend) = 0.01). However, no association was detected when the analysis was based on recent diet or cumulative updated diet. The updated analysis for total fluid intake and bladder cancer was attenuated compared with the original findings from the first 10-year follow-up period.

Replacing caloric beverages with water or diet beverages for weight loss in adults: main results of the Choose Healthy Options Consciously Everyday (CHOICE) randomized clinical trial

BACKGROUND

Replacement of caloric beverages with noncaloric beverages may be a simple strategy for promoting modest weight reduction; however, the effectiveness of this strategy is not known.

OBJECTIVE

We compared the replacement of caloric beverages with water or diet beverages (DBs) as a method of weight loss over 6 mo in adults and attention controls (ACs).

DESIGN

Overweight and obese adults [n = 318; BMI (in kg/m(2)): 36.3 ± 5.9; 84% female; age (mean ± SD): 42 ± 10.7 y; 54% black] substituted noncaloric beverages (water or DBs) for caloric beverages (≥200 kcal/d) or made dietary changes of their choosing (AC) for 6 mo.

RESULTS

In an intent-to-treat analysis, a significant reduction in weight and waist circumference and an improvement in systolic blood pressure were observed from 0 to 6 mo.Mean ((±SEM) weight losses at 6 mo were -2.5 ± 0.45% in the DB group, -2.03 ± 0.40% in the water group, and -1.76 ± 0.35% in the AC group; there were no significant differences between groups [corrected]. The chance of achieving a 5% weight loss at 6 mo was greater in the DB group than in the AC group (OR: 2.29; 95% CI: 1.05, 5.01; P = 0.04). A significant reduction in fasting glucose at 6 mo (P = 0.019) and improved hydration at 3 (P = 0.0017) and 6 (P = 0.049) mo was observed in the Water group relative to the AC group. In a combined analysis, participants assigned to beverage replacement were 2 times as likely to have achieved a 5% weight loss (OR: 2.07; 95% CI: 1.02, 4.22; P = 0.04) than were the AC participants.

CONCLUSIONS

Replacement of caloric beverages with noncaloric beverages as a weight-loss strategy resulted in average weight losses of 2% to 2.5%. This strategy could have public health significance and is a simple, straightforward message. This trial was registered at clinicaltrials.gov as NCT01017783.

Change in methodology for collection of drinking water intake in What We Eat in America/National Health and Nutrition Examination Survey: implications for analysis

Objective

To provide updated estimates of drinking water intake (total, tap, plain bottled) for groups aged ≥1 year in the USA and to determine whether intakes collected in 2005–2006 using the Automated Multiple-Pass Method for the 24 h recall differ from intakes collected in 2003–2004 via post-recall food-frequency type questions.

Design

Cross-sectional, observational study.

Setting

What We Eat in America (WWEIA), the dietary intake component of the US National Health and Nutrition Examination Survey (NHANES).

Subjects

Individuals aged ≥1 year in 2003–2004 (n 8249) and 2005–2006 (n 8437) with one complete 24 h recall.

Results

The estimate for the percentage of individuals who reported total drinking water in 2005–2006 was significantly (P < 0·0000) smaller (76·9 %) than that for 2003–2004 (87·1 %), attributable to a lower percentage reporting tap water (54·1 % in 2005–2006 v. 67·0 % in 2003–2004; P = 0·0001). Estimates of mean tap water intake differed between the survey cycles for men aged ≥71 years.

Conclusions

Survey variables must be examined before combining or comparing data from multiple WWEIA/NHANES release cycles. For at least some age/gender groups, drinking water intake data from NHANES cycles prior to 2005–2006 should not be considered comparable to more recent data.

Patterns and trends of beverage consumption among children and adults in Great Britain, 1986-2009

Many dietary recommendations include reduction of excessive intake of sugar-sweetened beverages (SSB) and other energy-rich beverages such as juices and alcohol. The present study examines surveys of both individual dietary intake data and household food expenditure surveys to provide a picture of patterns and trends in beverage intake and purchases in Great Britain from 1986 to 2009, and estimates the potential for pricing policy to promote more healthful beverage purchase patterns. In 2008-9, beverages accounted for 21, 14 and 18 % of daily energy intake for children aged 1·5-18 and 4-18 years, and adults (19-64 years), respectively. Since the 1990s, the most important shifts have been a reduction in consumption of high-fat dairy products and an increased consumption of fruit juices and reduced-fat milk among preschoolers, children and adolescents. Among adults, consumption of high-fat milk beverages, sweetened tea and coffee and other energy-containing drinks fell, but reduced-fat milk, alcohol (particularly beer) and fruit juice rose. In testing taxation as an option for shifting beverage purchase patterns, we calculate that a 10 % increase in the price of SSB could potentially result in a decrease of 7·5 ml/capita per d. A similar 10 % tax on high-fat milk is associated with a reduction of high-fat milk purchases by 5 ml/capita per d and increased reduced-fat milk purchase by 7 ml/capita per d. This analysis implies that taxation or other methods of shifting relative costs of these beverages could be a way to improve beverage choices in Great Britain.

Water balance throughout the adult life span in a German population

Mild dehydration, defined as a 1–2 % loss in body mass caused by fluid deficit, is associated with risks of functional impairments and chronic diseases. Whether water requirements change with increasing age remains unclear. Therefore, the aim of the present investigation is to quantify hydration status and its complex determining factors from young to old adulthood to analyse age-related alterations and to provide a reliable database for the derivation of dietary recommendations. Urine samples collected over a 24 h period and dietary records from 1528 German adults (18–88 years; sub-sample of the first National Food Consumption Survey) were used to calculate water intake (beverages, food and metabolic water) and water excretion parameters (non-renal water losses (NRWL), urine volume, obligatory urine volume) and to estimate hydration status (free-water-reserve) and ‘adequate intake (AI)’. Median total water intake (2483 and 2054 ml/d, for men and women, respectively (P < 0·0001)), decreased with increasing age only in males (P = 0·001). Obligatory urine volume increased in both sexes (P < 0·0001) due to decreased renal concentration capacity. The latter was balanced by a decrease of NRWL (P < 0·05), leaving the free-water-reserve and therefore hydration status almost unchanged. Calculated ‘AI’ of total water was the same for young (18–24 years) and elderly ( ≥ 65 years) adults (2910 and 2265 ml/d, for men and women, respectively). The present study is the first population-based examination showing that total water requirements do not change with age although ageing affects several parameters of water metabolism. Reduced sweat loss with increasing age appears to be primarily responsible for this observation.

Urine volume and change in estimated GFR in a community-based cohort study

BACKGROUND AND OBJECTIVES

The effect of increased fluid intake on kidney function is unclear. This study evaluates the relationship between urine volume and renal decline over 6 years in a large community-based cohort.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This prospective cohort study was undertaken in Canada from 2002 to 2008. We obtained 24-hour urine samples from adult participants with an estimated GFR (eGFR) ≥60 ml/min per 1.73 m(2) at study entry. Percentage annual change in eGFR from baseline was categorized as average decline <1% per year, between 1% and 4.9% (mild-to-moderate decline) or ≥5% (rapid decline).

RESULTS

2148 participants provided valid 24-hour urine samples, grouped as <1 L/d (14.5%); 1 to 1.9 L/d (51.5%); 2 to 2.9 L/d (26.3%); and ≥3 L/d (7.7%). Baseline eGFR for each category of urine volume was 90, 88, 84, and 87 ml/min per 1.73 m(2), respectively. Overall, eGFR declined by 1% per year, with 10% demonstrating rapid decline and 40% demonstrating mild-to-moderate decline. An inverse, graded relationship was evident between urine volume and eGFR decline: For each increasing category of 24-hour urine volume, percentage annual eGFR decline was progressively slower, from 1.3%, 1.0%, 0.8%, to 0.5%, respectively; P = 0.02. Compared with those with urine volume 1 to 1.9 L/d, those with urine volume ≥3 L/d were significantly less likely to demonstrate mild-to-moderate decline (adjusted odds ratio 0.66; 95% confidence interval 0.46 to 0.94) or rapid decline (adjusted odds ratio 0.46; 95% confidence interval 0.23 to 0.92); adjusted for age, gender, baseline eGFR, medication use for hypertension (including diuretics), proteinuria, diabetes, and cardiovascular disease.

CONCLUSIONS

In this community-based cohort, decline in kidney function was significantly slower in those with higher versus lower urine volume.

The Expanding Spectrum of Health Risks: Public Health or Harm?

Drawing on hydration as an illustrative case in point, this review discusses evidence-based perspectives on the continually expanding spectrum of promulgated health risks, including potential benefits and harms to public health. Future directions for inquiry and practice also are addressed.

Contemporary nutritional transition: determinants of diet and its impact on body composition

The world has experienced a marked shift in the global BMI distribution towards reduced undernutrition and increased obesity. The collision between human biology, shaped over the millennia and modern technology, globalization, government policies and food industry practices have worked to create far-reaching energy imbalance across the globe. A prime example is the clash between our drinking habits and our biology. The shift from water and breast milk as the only beverages available, to a vast array of caloric beverages was very rapid, shaped both by our tastes and aggressive marketing of the beverage industry. Our biology, shaped over millennia by daily consumption of water and seasonal availability of food, was not ready to compensate for the liquid energies. Other dietary changes were similarly significant, particularly the shift towards increased frequency of eating and larger portions. The roles of the food and beverage production, distribution and marketing sectors in not only shaping our diet but also accelerating these changes must be understood. Apart from the role of beverages, there is much less consensus about the role of various components of our diet in energy imbalance. Understanding the determinants of change in the key components of our diet through an array of research provides insights into some of the options we face in attempting to attain a great balance between energy intake and expenditures while creating an overall healthier dietary pattern. A few countries are systematically addressing the causes of poor dietary and physical activity patterns and high energy imbalance.

Impact of water intake on energy intake and weight status: a systematic review

The effects of consuming water with meals rather than drinking no beverage or various other beverages remain under-studied. This systematic review of studies reported in the English-language literature was performed to compare the effects of drinking water and various beverage alternatives on energy intake and/or weight status. Relevant clinical trials, epidemiologic studies, and intervention studies were identified and findings across the literature were summarized. From the clinical trials, average differences were calculated in total energy intake at test meals (DeltaTEI) for each of several beverage categories in comparison with water. The available literature for these comparisons is sparse and somewhat inconclusive. However, one of the most consistent sets of findings was related to adults drinking sugar-sweetened beverages (SSBs) versus water before a single meal. In these comparisons, total energy intakes were 7.8% higher (DeltaTEI range, -7.5 to 18.9) when SSBs were consumed. Studies comparing non-nutritive sweeteners with water were also relatively consistent and found no impact on energy intake among adults (DeltaTEI, -1.3; range, -9 to 13.8). Much less conclusive evidence was found in studies replacing water with milk and juice, with estimated increases in TEI of 14.9% (range, 10.9 to 23.9%). These findings from clinical trials, along with those from epidemiologic and intervention studies, suggest water has a potentially important role to play in reducing energy intake, and consequently in obesity prevention. A need for randomized-controlled trials to confirm this role exists.