Association Between Dietary Intake of Phosphorus and Measures of Obesity in the Jackson Heart Study.

BACKGROUND: The relation between phosphorus (P) intake and obesity is equivocal, with hypotheses in both directions. OBJECTIVES: We investigated the relationship between P intake, assessed from a current database, and calculated bioavailable P intake and obesity among African-American adults. METHODS: We examined associations between original and bioavailable P (total, added, and natural) and BMI and waist circumference (WC) in a cross-sectional study of 5306 African-American adults (21-84 y) from the Jackson Heart Study. A total of 3300 participants had complete interviews, valid dietary data, and normal kidney function. Diet was assessed by food frequency questionnaire. A novel algorithm was used to estimate P bioavailability. BMI or WC was regressed on each P variable, adjusting for total energy intake and potential confounders. RESULTS: After adjusting for covariates, original P (total and added) and bioavailable P (total and added) intakes (expressed/100 mg) were associated with BMI (ß: 0.11, 0.67, 0.31, and 0.71, respectively; all P < 0.0001). Neither original nor bioavailable natural P was significantly associated (ß: -0.03 and 0.09, respectively; both P > 0.05). When added and natural P were included in the same model, added P (original and bioavailable) intakes remained strongly associated with BMI (0.70 and 0.73, respectively; both P < 0.0001). Similar results were seen for WC. Intake of original added P tended to be more strongly associated with BMI, in females (ß: 0.72; P < 0.0001) than in males (ß: 0.56; P = 0.003) (P-interaction = 0.06). CONCLUSIONS: We found that greater intake of added, not natural, which may be a proxy for intake of processed foods was associated with higher BMI and WC. These were somewhat stronger when bioavailability was considered and for women than for men. Further investigation is needed to fully understand the mechanisms driving these associations.

Seeing the Whole Picture: Evaluating the Contribution of Whole Grains to Phosphorus Exposure in People With Kidney Failure Undergoing Dialysis Treatment.

Excessive dietary phosphorus is a concern among patients with kidney failure undergoing dialysis treatment because it may contribute to hyperparathyroidism and hyperphosphatemia. A long-standing but untested component of the low-phosphorus diet is the promotion of refined grains over whole grains. This paper reviews the scientific premise for restricting whole grains in the dialysis population and estimates phosphorus exposure from grain products based on three grain intake patterns modeled from reported intakes in the general US population, adjusting for the presence of phosphorus additives and phosphorus bioavailability: (1) standard grain intake, (2) 100% refined grain intake, and (3) mixed (50/50 whole and refined grain) intake. Although estimated phosphorus exposure from grains was higher with the mixed grain pattern (231 mg/day) compared to the 100% refined grain pattern (127 mg/day), the amount of additional phosphorus from grains was relatively low. Given the lack of strong evidence for restricting whole grains in people with CKD, as well as the potential health benefits of whole grains, clinical trials are warranted to address the efficacy and health impact of this practice.

Dairy product consumption, eating habits, sedentary behaviour and physical activity association with bone mineral density among adolescent boys: a cross-sectional observational study.

BACKGROUND: During childhood and adolescence, skeletal microarchitecture and bone mineral density (BMD) undergo significant changes. Peak bone mass is built and its level significantly affects the condition of bones in later years of life. Understanding the modifiable factors that improve bone parameters at an early age is necessary to early prevent osteoporosis. To identify these modifiable factors we analysed the relationship between dairy product consumption, eating habits, sedentary behaviour, and level of physical activity with BMD in 115 young boys (14-17 years). METHODS: Bone parameters were measured by dual energy x-ray absorptiometry using paediatric specific software to compile the data. Dairy product consumption and eating habits were assessed by means of a dietary interview. Sedentary behaviour and physical activity was assessed in a face-to-face interview conducted using the International Physical Activity Questionnaire. Data collection on total physical activity level was performed by collecting information on the number of days and the duration of vigorous and moderate intensity (MVPA) and average daily time spent in sitting (SIT time). RESULTS: The strongest relationships with BMD in distal part of forearm were found for moderate plus vigorous activity, sit time, and intake of dairy products, intake of calcium, protein, vitamin D, phosphorus from diet. Relationships between BMD, bone mineral content (BMC) in the distal and proximal part of the forearm and PA, sit time and eating parameters were evaluated using the multiple forward stepwise regression. The presented model explained 48-67% (adjusted R2 = 0.48-0.67; p < 0.001) of the variance in bone parameters. The predictor of interactions of three variables: protein intake (g/person/day), vitamin D intake (µg/day) and phosphorus intake (mg/day) was significant for BMD dis (adjusted R2 = 0.59; p < 0.001). The predictor of interactions of two variables: SIT time (h/day) and dairy products (n/day) was significant for BMD prox (adjusted R2 = 0.48; p < 0.001). Furthermore, the predictor of interactions dairy products (n/day), protein intake (g/person/day) and phosphorus intake (mg/day) was significant for BMC prox and dis (adjusted R2 = 0.63-0.67; p < 0.001). CONCLUSIONS: High physical activity and optimal eating habits especially adequate intake of important dietary components for bone health such as calcium, protein, vitamin D and phosphorus affect the mineralization of forearm bones.

A Systematic Review of Online Resources for the Dietary Management of Hyperphosphatemia in People With Chronic Kidney Disease.

OBJECTIVE: Internet search engines and social media websites are prominent and growing sources of dietary information for people with chronic kidney disease (CKD) and their healthcare providers. However, nutrition therapy for CKD is undergoing a paradigm shift, which may lead to inconsistent advice for managing hyperphosphatemia. The aim of this study was to summarize and evaluate online resources for phosphorus-specific nutrition therapy. DESIGN AND METHODS: Patient-facing resources were collected from Google, Yahoo, and Facebook in June-July 2021. Using nine independent search terms, the first 100 hits were reviewed. Dietary advice for food types, food groups, food subgroups, and individual food items was categorized as "restricted," "recommended," "mixed," and "not mentioned." Information on publication date, source, and author(s), phosphorus bioavailability, and demineralization were also collected. RESULTS: After removing duplicates, 199 resources from Google and Yahoo and 33 from Facebook were reviewed. Resources ranged from 2005 to 2021 and were primarily authored by registered dietitians and medical doctors (65% and 31%, respectively). Dietary advice mostly focuses on restricting high-phosphorus foods and phosphorus additive-based processed foods. Dietary restrictions were generally consistent with the traditional low-phosphorus diet, which targets whole grains, dairy, and plant-based protein foods, although major inconsistencies were noted. Phosphorus bioavailability and demineralization were rarely mentioned (16% and 8%, respectively). Similar findings were found on Facebook, but the limited number of resources limited meaningful comparisons. CONCLUSION: Results showed that online resources for phosphorus-specific nutrition therapy are highly restrictive of heart-healthy food items and contain significant inconsistencies. Given the widespread and increasing use of online resources by people with CKD and health care professionals to inform dietary choices, efforts are urgently needed to establish consensus for phosphorus-specific nutrition therapy. Until then, the findings of this study provide a basis for increasing awareness of the potential for confusion arising from online resources.

Effect of dietary phosphorus deprivation during the dry period on the liver transcriptome of high-yielding periparturient dairy cows.

Although dietary phosphorus (P) deprivation extending from the dry period into early lactation impairs health and productivity of cows, restricting dietary P supply during the dry period not only appears to be innocuous but rather effectively mitigates hypocalcemia during the first wk of lactation. To investigate possible negative metabolic effects of P deprivation during the dry period, the present study tested the hypothesis that restricted dietary P supply during the dry period alters the liver transcriptome of dairy cows during the periparturient period. Thirty late-pregnant multiparous Holstein-Friesian dairy cows entering their second, third, or fourth lactation were assigned to either a dry cow ration with low (LP, 0.16% P in DM) or adequate P content (AP, 0.35% in DM) during the last 4 wk of the dry period (n = 15/group). Liver transcriptomics, which was carried out in a subset of 5 second-parity cows of each group (n = 5), and determination of selected hormones and metabolites in blood of all cows, was performed ∼1 wk before calving and on d 3 postpartum. Liver tissue specimens and blood samples were obtained by a micro-invasive biopsy technique from the right tenth intercostal space and puncture of a jugular vein, respectively. One hundred seventy-five hepatic transcripts were expressed differentially between LP versus AP cows in late pregnancy, and 165 transcripts differed between LP versus AP cows in early lactation (fold change >1.3 and <-1.3, P < 0.05). In late pregnancy, the enriched biological processes of the upregulated and the downregulated transcripts were mainly related to immune processes and signal transduction (P < 0.05), respectively. In early lactation, the enriched biological processes of the upregulated and the downregulated transcripts were involved in mineral transport and biotransformation (P < 0.05), respectively. The plasma concentrations of the hormones and acute-phase proteins (progesterone, insulin-like growth factor 1, serum amyloid α, haptoglobin, and 17ß-estradiol) determined were not affected by P supply. These results suggest that P deprivation during the dry period moderately affects the liver transcriptome of cows in late pregnancy and early lactation, and causes no effects on important plasma hormones and acute-phase proteins indicating no obvious impairment of health or metabolism of the cows.

Hyperparathyroidism, Serum Phosphorus and Dietary Intake in Hemodialysis Patients: Is There a Novel Relationship?

The management of hyperparathyroidism (intact parathyroid hormone (iPTH) serum levels > 585 pg/mL), frequently focuses on the appropriate control of mineral and bone markers, with the decrease in serum and dietary phosphorus as two of the targets. We aimed to investigate the association between iPTH, serum phosphorus levels and dietary intake. This was a cross-sectional, multicenter, observational study with 561 patients on hemodialysis treatment. Clinical parameters, body composition and dietary intake were assessed. For the analysis, patients were divided into three groups: (a) iPTH < 130, (b) iPTH between 130 and 585 and (c) iPTH > 585 pg/mL. The association between PTH, serum phosphorus and dietary intake was analyzed using linear regression models. In the whole sample, 23.2% of patients presented an iPTH > 585 pg/mL. Patients with higher iPTH levels were those with longer HD vintage and lower ages, higher serum phosphorus, serum calcium, Ca/P product, albumin and caffeine intake, and a lower dietary intake of phosphorus, fiber, riboflavin and folate. Higher serum phosphorus predicted higher iPTH levels, even in the adjusted model. However, lower dietary phosphorus and fiber intake were predictors of higher iPTH levels, including in the adjusted model. Our results bring new data to the relationship between dietary intake and iPTH values. Despite higher serum phosphorus being observed in patients with HPTH, an opposite association was noted regarding dietary phosphate and fiber.

Effect of 25-hydroxycholecalciferol supplementation with different dietary available phosphorus levels for broilers.

1. Based on the hypothesis that 25-hydroxycholecalciferol (25-OH-D3) inclusion would optimise dietary mineral digestibility and ameliorate growth performance and bone mineralisation in available phosphorus (AvP) deficient-fed broilers, a trial was conducted to evaluate its effect on diets with different levels of AvP.2. Broilers aged 1-21 d were randomly assigned one of the eight treatments, consisting of four dietary levels of AvP (0.45%, 0.42%, 0.39%, and 0.36%) and with or without supplementation with 25-OH-D3 at 69 µg/kg of feed. All diets contained 100 µg/kg of vitamin D3 (cholecalciferol).3. The addition of 25-OH-D3 resulted in higher feed intake and body weight gain, and lower FCR (P < 0.05) compared to non-supplemented diets, whereas AvP levels had a quadratic effect only on feed intake. There were no interactions between treatment factors.4. Increasing AvP levels linearly reduced the ileal digestibility of Ca and P (P < 0.01) and supplementing 25-OH-D3 increased both Ca and P ileal digestibility (P < 0.05), without any interactions observed for ileal digestibility.5. There was an interaction, whereby 25-OH-D3 inclusion increased serum metabolites in broilers fed 0.36% to 0.42% AvP compared to the non-supplemented diets (P < 0.001), whereas, at 0.45% AvP, diets with or without 25-OH-D3 had similar results.6. The P content in bone linearly increased in line with AvP levels (P < 0.05) and supplementation of 25-OH-D3 increased ash bone content (P < 0.001).7. Broilers can benefit from 25-OH-D3 supplementation combined with cholecalciferol with regard to Ca and P utilisation and vitamin D status, allowing for a reduction of dietary AvP levels down to 0.36% without impairing growth performance or bone status.

Effect of limestone particle size and microbial phytase on phosphorus and calcium digestion kinetics along the gastrointestinal tract in laying hens.

1. This study assessed the effect of limestone particle size and microbial phytase incorporation on the fate of phosphorus (P) and calcium (Ca) along the gastrointestinal tract in 72 laying hens.2. Four experimental diets were formulated according to a 2 × 2 factorial arrangement to evaluate the effect of two coarse limestone (CL) inclusion. This included a mix (MIX) of 75% CL (2 - 4 mm) and 25% fine particles (FL, <0.5 mm) or 100% FL, in two different basal diets formulated without (MIX0 and FL0) or with 300 FTU of microbial phytase/kg (MIX300 and FL300).3. Contents of the crop, gizzard, duodenum, jejunum and ileum were collected to determine the mean retention time (MRT) of dry matter (DM), the recovery rate of Ca and P in each segment of the gastrointestinal tract and the apparent fractional digestibility coefficient (AD) of Ca and P in each intestinal segment.4. In hens fed FL, microbial phytase decreased the MRT of DM along the intestine (p < 0.05). In the crop and the gizzard, Ca recovery increased with MIX incorporation to a greater extent in hens fed without microbial phytase (p < 0.05). The mixed particle size incorporation decreased absorption kinetics of Ca in hens fed microbial phytase. The AD of P and the absorption kinetics of P were significantly decreased in hens receiving FL300, probably due to complex formation between Ca and phytic acid.5. This study showed that coarse limestone particles incorporation improved mineral utilisation along the digestive tract.

Supplemental phosphorus can be completely replaced with microbial phytase in White Leghorn layer diets.

1. A study was conducted to assess the possibility of totally replacing supplemental phosphorus sources in White Leghorn (WL) layer diets (aged 28 to 45 weeks of age) with microbial phytase supplementation. One thousand commercial layers (HyLine White) of 28 weeks of age were housed in California cages fitted in open-sided poultry shed at the rate of 20 layers in each replicate. Ten replicates were randomly allotted to each treatment, and the respective diet was fed from 28 to 45 weeks of age.2. A control diet (CD) containing the recommended levels of non-phytate phosphorus (3.6 g/kg NPP) and four other test diets (2-5) having sub-optimal levels of NPP (2.4, 2.0, 1.6 and 1.2 g/kg), but with supplemental microbial phytase (600 FTU/kg) were prepared and fed for the trial duration.3. The layers fed with lower levels of NPP with phytase had the same laying performance as the group fed the CD. Egg production, feed efficiency, egg mass, shell defects, egg density, shell weight, shell thickness, ash content and breaking strength of the tibia and sternum were not affected by feeding the lowest concentration of NPP (1.2 g/kg) plus microbial phytase.4. Phytase supplementation in diets with sub-optimal levels of NPP (2.4, 2 and 1.6 g/kg) significantly improved the Haugh unit score compared to those fed the CD.5. It was concluded that supplemental phosphorus can be completely replaced with microbial phytase (600 FTU/kg) in a diet without affecting egg production, shell quality or bone mineral variables in WL layers (28 to 45 weeks).

Dietary phosphorus requirement of silver CARP (Hypophthalmichthys molitrix) fingerlings.

The aim of this study was to determine the optimal dietary phosphorus (P) requirement and its effects on growth performance, body composition, mineralization and alkaline phosphate (ALP) activity in silver carp (Hypophthalmichthys molitrix). A total of 360 fish with an average initial weight of 7.0 ± 0.15 g were divided into 18 tanks (70 L capacity each) with a stocking density of 20 fish per tank in triplicate. The fish were fed diets containing six levels of P (3.3, 4.4, 5.5, 6.5, 7.5 and 8.6 g/kg) up to satiation for 90 days twice daily at 09:00 and 16:00. The results showed that fish fed diets containing 6.5 and 7.5 g/kg dietary P had significantly higher (p < 0.05) growth performance in terms of final weight gain, average weight gain (AWG), weight gain% (WG%), protein efficiency ratio (PER) and specific growth rate (SGR) than fish fed other diets. The best value of the feed conversion ratio (FCR) was observed in fish fed the 6.5 g/kg P diet, which was not significantly different from the 7.5 g/kg P diet. Increasing P supplementation above 6.5 g/kg significantly reduced (p < 0.05) the feed intake of silver carp. Whole-body composition analysis indicated that increasing P levels resulted in a decrease (p < 0.05) in crude fat (CF) and an increase (p < 0.05) in crude ash (CA) content, while crude protein (CP) and moisture content remained unaffected (p > 0.05). Fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Ca content in the whole body, bones and scales compared to those fed diets containing ≤5.5 g/kg P. A similar trend was observed for P and Mg contents in the whole body, bones and scales. The Zn content tended to decrease (p < 0.05) with increasing P supplementation in the whole body and bones, but fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Zn content compared to fish fed diets containing ≤5.5 g/kg P. The Ca/P ratio was significantly affected by P supplementation. Fish fed diets containing ≥6.5 g/kg P had significantly higher (p < 0.05) Ca and P contents in the serum than fish fed other diets. ALP activity increased (p < 0.05) with increasing P levels up to 6.5 g/kg P and decreased (p < 0.05) thereafter. In conclusion, supplementing P up to 6.35 g/kg is recommended for the optimal growth of silver carp.

Influences of dietary-reduced nitrogen (N) and phosphorus (P) on chemical body composition, N and P retention and health traits of contemporary barrows.

Farmgate balances are used as a tool for monitoring nutrient surpluses at farm level. In Germany, preparation of farmgate balances is legally mandatory and also requires data on chemical body composition, especially concentration of nitrogen (N) and phosphorus (P), of farm animals. It is well known that increased N and P efficiency results in lowered N and P excretions with the manure and therefore mitigates negative consequences of high N and P release into the environment (e.g. eutrophication of surface waters), especially in areas with high livestock density. In this context, feeding N- and P-reduced diets can be a strategy for increasing N and P efficiency in fattening pigs. To investigate the influence of N- and P-reduced diets on chemical body composition of barrows and to update current used data basis, 8 barrows were slaughtered after a balance trial and their bodies were subjected to full body analysis. During the balance trial, pigs received the control diet (CON) meeting common nutrient requirements or the N- and P-reduced diet (NPred) in a three-phased feeding regimen (n = 4/diet, 3 weeks/phase). Pigs were slaughtered with an average live weight (LW) of 123.3 ± 7.5 kg and carcasses were manually dissected in four fractions. Fractions were analysed for nutrient concentration. Furthermore, organs were weighed individually and blood serum was sampled during exsanguination. Serum samples were analysed for clinical-chemical traits. Chemical body composition did not significantly differ between NPred- and CON-fed pigs. N concentration was 23.3 ± 0.3 and 24.5 ± 1.0 g/kg, P concentration was 5.2 ± 0.1 and 5.5 ± 0.4 g/kg in the empty body of NPred- and CON-fed pigs (p = 0.073, 0.164). N and P retention between the experiment's start and slaughter did not differ between the feeding groups (p = 0.641, 0.240). Variables related to liver integrity, energy metabolism and electrolytes were similar between CON- and NPred-fed pigs. Traits related to protein metabolism showed significantly reduced concentrations of urea and albumin in NPred-fed pigs (p = 0.013, 0.025), but no hypoalbuminaemia. Results suggest that N- and P-reduced feeding does not significantly affect chemical body composition of contemporary barrows.

Effect of Dietary Phosphate Restriction in Pre-Dialysis Chronic Kidney Disease Patients with Hyperphosphataemia in Southern Nigeria.

BACKGROUND: Hyperphosphataemia is a common cardiovascular risk factor in chronic kidney disease (CKD). Dietary counseling and control are key aspects in the management of CKD. Although some studies have shown the beneficial effects of dietary phosphate restriction on cardiovascular and bone health in haemodialysis patients, little is known about its effect in pre-dialysis CKD patients. AIM: To determine the effect of dietary phosphate restriction in predialysis CKD patients with hyperphosphataemia. METHODS: A hospital-based interventional study involving 72 predialysis CKD patients with hyperphosphataemia randomly allocated into 2 groups. Group 1 had nutritional counseling on dietary phosphate restriction while group 2 had no form of dietary phosphate restriction. All participants were placed on a phosphate binder throughout the study period of 3 months. At the end of the third month, a repeat of baseline tests (serum phosphate, calcium, albumin, creatinine and serum lipids) and anthropometric measurements were done and compared between the 2 groups. RESULTS: The mean age in the treatment and control groups were 54.6±14.7 years and 54.9±14.5 years, respectively. The mean serum phosphate (5.7±0.5 vs. 5.5± 0.4mg/dl), calcium (7.9±0.9 vs. 7.8± 0.7mg/dl), albumin (3.8±0.4 vs. 3.9±0.7g/dl), creatinine (3.9±1.3 vs. 3.7±1.2mg/dl) and body mass index (BMI) (25.0±3.9 vs.25.4±3.1kg/m2) were similar in both groups. Serum phosphate, potassium, fasting blood glucose (FBG), total cholesterol, triglycerides and BMI were significantly reduced while there was no significant change in serum calcium-phosphate product and haematocrit following dietary phosphate restriction in addition to use of phosphate binders. However, on comparison of the changes between the treatment and control groups preand post- intervention, there was no significant change in serum phosphate but there was significant decrease in serum potassium, triglyceride and FBG. CONCLUSION: The use of phosphate binders in pre-dialysis CKD significantly reduced serum phosphate while additional dietary phosphate restriction had no significant effect on serum phosphate lowering and there was no significant change in nutritional status in predialysis CKD patients with hyperphosphataemia.

CONTEXTE: L'hyperphosphatémie est un facteur de risque cardiovasculaire courant dans la maladie rénale chronique (MRC). Le conseil et le contrôle diététiques sont des aspects clés dans la gestion de la MRC. Bien que certaines études aient montré les effets bénéfiques de la restriction alimentaire en phosphate sur la santé cardiovasculaire et osseuse chez les patients en hémodialyse, peu est connu sur son effet chez les patients atteints de MRC pré-dialyse. OBJECTIF: Déterminer l'effet de la restriction alimentaire en phosphate chez les patients atteints de MRC pré-dialyse avec hyperphosphatémie. MÉTHODES: Étude interventionnelle hospitalière impliquant 72 patients atteints de MRC pré-dialyse avec hyperphosphatémie, répartis aléatoirement en 2 groupes. Le groupe 1 a reçu des conseils nutritionnels sur la restriction alimentaire en phosphate tandis que le groupe 2 n'a reçu aucune forme de restriction alimentaire en phosphate. Tous les participants ont été mis sous un chélateur de phosphate pendant toute la période d'étude de 3 mois. À la fin du troisième mois, les tests de base (phosphate sérique, calcium, albumine, créatinine et lipides sériques) et les mesures anthropométriques ont été répétés et comparés entre les 2 groupes. RÉSULTATS: L'âge moyen dans les groupes traitement et contrôle était respectivement de 54,6±14,7 ans et 54,9±14,5 ans. Les moyennes du phosphate sérique (5,7±0,5 contre 5,5±0,4 mg/dl), du calcium (7,9±0,9 contre 7,8±0,7 mg/dl), de l'albumine (3,8±0,4 contre 3,9±0,7 g/dl), de la créatinine (3,9±1,3 contre 3,7±1,2 mg/dl) et de l'indice de masse corporelle (IMC) (25,0±3,9 contre 25,4±3,1 kg/m2) étaient similaires dans les deux groupes. Le phosphate sérique, le potassium, la glycémie à jeun (GAJ), le cholestérol total, les triglycérides et l'IMC ont été significativement réduits, tandis qu'il n'y avait aucun changement significatif dans le produit calcium-phosphate sérique et l'hématocrite suite à la restriction alimentaire en phosphate en plus de l'utilisation de chélateurs de phosphate. Cependant, en comparant les changements entre les groupes traitement et contrôle avant et après l'intervention, il n'y avait pas de changement significatif du phosphate sérique, mais il y avait une diminution significative du potassium sérique, des triglycérides et de la GAJ. CONCLUSION: L'utilisation de chélateurs de phosphate chez les patients atteints de MRC pré-dialyse a significativement réduit le phosphate sérique, tandis que la restriction alimentaire en phosphate supplémentaire n'a eu aucun effet significatif sur la réduction du phosphate sérique et il n'y avait aucun changement significatif de l'état nutritionnel chez les patients atteints de MRC pré-dialyse avec hyperphosphatémie. MOTS-CLÉS: Maladie rénale chronique, Pré-dialyse, Hyperphosphatémie, Restriction alimentaire.

A U-shaped association between dietary phosphorus intake and new-onset hypertension: a nationwide cohort study in China.

BACKGROUND: The association between dietary phosphorus intake and the risk of hypertension remains uncertain. We aimed to investigate the relation of dietary phosphorus intake with new-onset hypertension among Chinese adults. METHODS: A total of 12,177 participants who were free of hypertension at baseline from the China Health and Nutrition Survey (CHNS) were included. Dietary intake was measured by 3 consecutive 24-hour dietary recalls combined with a household food inventory. New-onset hypertension was defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg or diagnosed by a physician or under antihypertensive treatment during the follow-up. RESULTS: During a median follow-up of 6.1 years, 4,269 participants developed new-onset hypertension. Overall, the association between dietary phosphorus intake and new-onset hypertension followed a U-shape (P for nonlinearity<.001). Consistently, when dietary phosphorus intake was assessed as quintiles, compared with those in the 3rd to 4th quintiles (912.0-<1089.5 mg/d), a significantly higher risk of new-onset hypertension was found in participants in the 1st to 2nd quintiles (<912.0 mg/d: HR, 1.23; 95% CI, 1.14-1.33), and the fifth quintile (≥1089.5 mg/d: HR, 1.21; 95% CI, 1.10-1.33). CONCLUSION: There was a U-shaped association between dietary phosphorus intake and new-onset hypertension in general Chinese adults.

Phosphorus absorption kinetics and exudation strategies of roots developed by three lupin species to tackle P deficiency.

MAIN CONCLUSION: Different lupin species exhibited varied biomass, P allocation, and physiological responses to P-deprivation. White and yellow lupins had higher carboxylate exudation rates, while blue lupin showed the highest phosphatase activity. White lupin (Lupinus albus) can produce specialized root structures, called cluster roots, which are adapted to low-phosphorus (P) soil. Blue lupin (L. angustifolius) and yellow lupin (L. luteus), which are two close relatives of white lupin, do not produce cluster roots. This study characterized plant responses to nutrient limitation by analyzing biomass accumulation and P distribution, absorption kinetics and root exudation in white, blue, and yellow lupins. Plants were grown in hydroponic culture with (64 µM NaH2PO4) or without P for 31 days. Under P limitation, more biomass was allocated to roots to improve P absorption. Furthermore, the relative growth rate of blue lupin showed the strongest inhibition. Under + P conditions, the plant total-P contents of blue lupin and yellow lupin were higher than that of white lupin. To elucidate the responses of lupins via the perspective of absorption kinetics and secretion analysis, blue and yellow lupins were confirmed to have stronger affinity and absorption capacity for orthophosphate after P-deprivation cultivation, whereas white lupin and yellow lupin had greater ability to secrete organic acids. The exudation of blue lupin had higher acid phosphatase activity. This study elucidated that blue lupin was more sensitive to P-scarcity stress and yellow had the greater tolerance of P-deficient condition than either of the other two lupin species. The three lupin species have evolved different adaptation strategies to cope with P deficiency.

Association between dietary phosphorus intake and chronic constipation in adults: evidence from the National Health and Nutrition Examination Survey.

BACKGROUND: Several studies suggest a link between micronutrients and constipation. However, the relationship between constipation and phosphorus has rarely been examined. The main aim of this study was to investigate the association between changes in the prevalence of chronic constipation and dietary phosphorus intake among adult respondents of the National Health and Nutritional Examination Survey (NHANES). METHODS: Data were extracted from the NHANES database for the years 2005-2010. A total of 13,948 people were included in the analysis. Dietary information was collected using the respondents' 24-h dietary records. We conducted multiple logistic regression analyses to examine the correlation between phosphorus intake and poor bowel movement. The primary and secondary outcomes was constipation defined by stool consistency and stool frequency, respectively. RESULTS: Following multi-variate adjustment in model III, a significant association between chronic constipation and each additional 0.1-g intake of dietary phosphorus (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.95, 1.00; P = 0.034 for stool consistency vs. OR, 0.94; 95% CI, 0.90, 0.99; P = 0.027 for stool frequency) was observed. Following multi-variate adjustment in model III, OR values and 95% CI from the second to fourth quartiles compared to the first quartile (reference group) were 0.92 (0.66, 1.27), 0.73 (0.47, 1.13), and 0.39 (0.20, 0.76), respectively, using the stool frequency definition. CONCLUSIONS: This study revealed a negative correlation between phosphorus intake and chronic constipation. This may be due to the fact that dietary phosphorus intake is associated with softer stools and increased stool frequency. Further studies in different settings should be considered to verify these findings.

A U-shaped association between dietary phosphorus intake and new-onset diabetes: A nationwide cohort study in China.

BACKGROUND AND AIMS: The association between dietary phosphorus intake and the risk of diabetes remains uncertain. We aimed to investigate the relation of dietary phosphorus intake with new-onset diabetes among Chinese adults. METHODS AND RESULTS: A total of 16,272 participants who were free of diabetes at baseline from the China Health and Nutrition Survey were included. Dietary intake was measured by 3 consecutive 24-h dietary recalls combined with a household food inventory. Participants with self-reported physician-diagnosed diabetes, or fasting glucose ≥7.0 mmol/L or glycated hemoglobin ≥6.5% during the follow-up were defined as having new-onset diabetes. During a median follow-up of 9.0years, 1101 participants developed new-onset diabetes. Overall, the association between dietary phosphorus intake with new-onset diabetes followed a U-shape (P for nonlinearity<0.001). The risk of new-onset diabetes significantly decreased with the increment of dietary phosphorus intake (per SD increment: HR, 0.64; 95%CI, 0.48-0.84) in participants with phosphorus intake <921.6 mg/day, and increased with the increment of dietary phosphorus intake (per SD increment: HR, 1.33; 95%CI, 1.16-1.53) in participants with phosphorus intake ≥921.6 mg/day. Consistently, when dietary phosphorus intake was assessed as quintiles, compared with those in the 3rd quintile (905.0-<975.4 mg/day), significantly higher risks of new-onset diabetes were found in participants in the 1st-2nd quintiles (<905.0 mg/day: HR, 1.59; 95%CI, 1.30-1.94), and 4th-5th quintiles (≥975.4 mg/day: HR, 1.46; 95%CI, 1.19-1.78). CONCLUSIONS: There was a U-shaped association between dietary phosphorus intake and new-onset diabetes in general Chinese adults, with an inflection point at 921.6 mg/day and a minimal risk at 905.0-975.4 mg/day of dietary phosphorus intake.

Family-centered empowerment approach to optimize phosphate management among hemodialysis patients: an experimental study.

BACKGROUND: This study aimed to investigate the effect of a family-centered empowerment program on hyperphosphatemia management. METHOD: This experimental study was performed on 80 randomly selected eligible patients with hyperphosphatemia undergoing hemodialysis. Patients were assigned randomly to two groups of family-centered empowerment program (FCEPG) and control group (CG) by coin toss (40 people per group). Data collection tools were the researcher-made Phosphate Control Knowledge Scale, the researcher-made Adherence to Dietary Restriction of Phosphorus Intake Scale, the eight-item Morisky Medication Adherence Scale, and serum phosphorus measurements. Data were collected before the intervention, one month, and three months after the intervention. Patients in FCEPG participated in a family-centered empowerment program. The statistical significance level was considered to be 0.05. RESULTS: Inter-group comparisons showed no significant difference between FCEPG and CG in terms of the mean score of knowledge of phosphate control, adherence to dietary restriction of phosphorus intake, adherence to medication, and the mean serum phosphorus level before the empowerment program, but showed significant differences between them in these respects at one month after the program and three months after the program (p < 0.05). Intra-group comparisons showed a significant difference in FCEPG between the mean and standard deviation of all four variables before the empowerment program and the corresponding values one month and three months after the program (P < 0.05). CONCLUSION: The findings of this study can be used in various fields of healthcare in the hospital and community.

Maternal diet during breastfeeding in correlation to calcium and phosphorus concentrations in human milk.

BACKGROUND: The impact of maternal diet on mineral concentration in human milk (HM) remains unclear. The main aim of this study was to investigate the relationship between maternal dietary intake and calcium and phosphorus concentrations in HM. Furthermore, we aimed to evaluate the intake of both minerals by exclusively breastfed infants. METHODS: HM samples were obtained from 30 mothers at 6-8 weeks postpartum. Each mother was asked to express pre- and postfeeding milk four times during a 24-h period (6.00-12.00, 12.00-18.00, 18.00-24.00, 24.00-6.00). Maternal dietary assessment was based on a food frequency questionnaire and 3-day dietary records. Analysed minerals were determined using an inductively coupled plasma mass spectrometer (NexION 300D ICP mass spectrometer, Perkin Elmer SCIEX). RESULTS: The mean concentrations of calcium and phosphorus in HM samples were 278.7 ± 61.0 and 137.1 ± 21.9 mg/L, respectively, maintaining 2:1 ratio by weight. The concentration of both minerals was correlated with each other (r = 0.632, p = <0.001). The infants' mean calcium intake was 149.53 ± 36.41 mg/L, and their mean phosphorus intake was 74.62 ± 19.41 mg/L. The risk of insufficient intake of calcium was reported in 60% of infants (n = 18). Spearman's/Pearson's correlation coefficients did not reveal any correlations between HM calcium concentration and maternal diet, contrary to HM phosphorus concentration, which was positively correlated with energy (r = 0.369, p = 0.045), total protein (r = 0.464, p = 0.01), calcium (r = 385, p = 0.036), phosphorus (r = 501, p = 0.005), niacin (p < 0.001) and pyridoxine (r = 382, 0.037) intake. However, in multivariable analysis we observed that maternal dietary intake of both minerals had a positive influence on their concentration in HM. CONCLUSIONS: Maternal calcium and phosphorus intake influenced the concentration of both minerals in HM; however, the relationship was rather weak. In addition, we observed that calcium intake by most of the exclusively breastfed infants was insufficient to meet the recommended daily intake.

Phosphorus Additives and Their Impact on Phosphorus Content in Foods-An Analysis of the USDAs Branded Foods Product Database.

OBJECTIVES: The frequency of phosphate additives reported in the United States Department of Agriculture Branded Foods Product Database and how these additives impact phosphate content is unknown. METHODS: All products included in the Branded Foods Product Database reporting phosphorus content were reviewed for presence of phosphate salts and/or lecithin additives. RESULTS: Phosphorus content information was available for 3,466 (1.45%) food items, of these 1791 (51.6%) contained additives. Median phosphorus content was lowest in products with lecithin only compared to products without phosphorus additives (86 [54-200] vs. 145 [77-351] mg per 100 g, P < .01), which was not different from products with phosphate salts (176 [101-276] mg per 100 g, P = .22) or products with both phosphate salts and lecithin (161 [99-285] mg per 100 g, P = 1.00). The impact of a phosphorus salt on phosphorus content (mg per 100) was explored among ultra-processed products grouped by similar phosphorus contents. The phosphorus content of in in nondairy alternatives, dairy, plant proteins, and grains were significantly higher when the product contained a phosphate salt compared to products without a phosphate salt. For all products phosphorus and potassium content were correlated, but the relationship was stronger for when a potassium phosphate additive was present compared to absent (rho = 0.81 vs. 0.53, P < .05). Similar patterns were seen for sodium, calcium, and iron with stronger correlations with phosphate content for products with additives than those without (calcium phosphate: rho = 0.47 vs. 0.32; iron phosphate: rho = 0.47 vs. 0.33; sodium phosphate: rho = 0.45 vs. 0.07. All P < .05). The relationship between phosphate and sodium for products without phosphate additives was weak. CONCLUSIONS: Lecithin may not be associated with increased phosphorus content. Calcium, potassium, sodium, and iron phosphorus salts appear to be associated with increases in the composite mineral and phosphorus content, with the strongest correlation between potassium and phosphorus content.

'Phos'tering a Clear Message: The Evolution of Dietary Phosphorus Management in Chronic Kidney Disease.

Phosphorus is a vital nutrient, but disturbances in phosphorus homeostasis are central to chronic kidney disease-mineral and bone disorder. To minimize disturbances, traditional dietary guidance focused on a numerical phosphorus target leading to the exclusion of many healthy foods and implementation challenges. Contemporary phosphorus guidance focuses on dietary source, avoiding additives, and emphasizing low-phosphorus bioaccessibility foods, leading to a more liberal approach. Additional work is needed to demonstrate the efficacy of these contemporary approaches and understand the influence of specific foods, processing, and cooking methods. Unfortunately, patient education using traditional and contemporary strategies may give mixed messages, particularly related to plant-based foods. Thus, greater clarity on the effects of specific foods and dietary patterns may improve phosphorus education. This review aims to discuss the evolution of dietary phosphorus management while highlighting areas for future research that can help move the field toward stronger evidence-based guidance to prevent and treat hyperphosphatemia.