Skip to main content

Main menu

  • Home
  • Content
    • Published Ahead of Print
    • Current Issue
    • Podcasts
    • Subject Collections
    • Archives
    • ASN Meeting Abstracts
    • Saved Searches
  • Authors
    • Submit a Manuscript
    • Author Resources
    • Reprint Information
  • Trainees
    • Peer Review Program
    • Prize Competition
  • About CJASN
    • About CJASN
    • Editorial Team
    • CJASN Impact
    • CJASN Recognitions
  • More
    • Alerts
    • Advertising
    • Reprint Information
    • Subscriptions
    • Feedback
  • ASN Kidney News
  • Other
    • JASN
    • Kidney360
    • Kidney News Online
    • American Society of Nephrology

User menu

  • Subscribe
  • My alerts
  • Log in
  • My Cart

Search

  • Advanced search
American Society of Nephrology
  • Other
    • JASN
    • Kidney360
    • Kidney News Online
    • American Society of Nephrology
  • Subscribe
  • My alerts
  • Log in
  • My Cart
Advertisement
American Society of Nephrology

Advanced Search

  • Home
  • Content
    • Published Ahead of Print
    • Current Issue
    • Podcasts
    • Subject Collections
    • Archives
    • ASN Meeting Abstracts
    • Saved Searches
  • Authors
    • Submit a Manuscript
    • Author Resources
    • Reprint Information
  • Trainees
    • Peer Review Program
    • Prize Competition
  • About CJASN
    • About CJASN
    • Editorial Team
    • CJASN Impact
    • CJASN Recognitions
  • More
    • Alerts
    • Advertising
    • Reprint Information
    • Subscriptions
    • Feedback
  • ASN Kidney News
  • Visit ASN on Facebook
  • Follow CJASN on Twitter
  • CJASN RSS
  • Community Forum
Editorials
You have accessRestricted Access

Source Matters: From Phosphorus Load to Bioavailability

Masafumi Fukagawa, Hirotaka Komaba and Ken-ichi Miyamoto
CJASN February 2011, 6 (2) 239-240; DOI: https://doi.org/10.2215/CJN.11051210
Masafumi Fukagawa
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Hirotaka Komaba
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Ken-ichi Miyamoto
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Info & Metrics
  • View PDF
Loading

Phosphorus plays crucial roles in the development of mineral and bone disorders including secondary hyperparathyroidism and vascular calcification, which eventually result in high risk for cardiovascular events and effect on survival in patients with chronic kidney disease (CKD) (1). Such an effect of phosphorus load on survival has also been demonstrated in general populations. Contribution of phosphorus load to abnormal mineral metabolism already starts from the early stages of CKD, still without significant increase of its serum level (2,3). Such effects of phosphorus load in early stages of CKD are presumably mediated by the increase of fibroblast growth factor 23 (FGF23) secretion from the bone (3,4). Although diurnal variation in serum phosphorus including postprandial changes may also contribute to the development of mineral and bone disorders and their related outcomes, these data support the importance of controlling dietary phosphorus load as well as of its serum concentration.

Except for several trials to inhibit active phosphate transport from the intestine through Na/Pi IIb (5), control of phosphorus load has been traditionally attempted by restriction of dietary phosphorus intake, mostly by that of protein, and by the use of phosphate binders (6). In addition to such strategies, recent reports suggested that the source of phosphorus, not just its content, should be considered in food (7).

Phosphorus in food is provided in the form of either inorganic phosphate or organic phosphate. Inorganic phosphate is readily absorbable. Thus, its overload by food additives and preservatives has recently emerged as another serious issue for patients with CKD (8,9). Absorption of organic phosphate derived from protein is lower. Moreover, absorption of phosphorus derived from plants may be different from that derived from meat. Phosphorus in meat is present within the cells as organic phosphates, which is easily hydrolyzed and absorbed. By contrast, phosphorus in plants, such as seeds, nuts, and legumes, is mostly in the form of phytate (10). Because mammals lack the degrading enzyme phytase, bioavailability of phosphorus from plant-derived foods is relatively low, despite their high phosphorus content.

Such difference in the bioavailability of phosphorus should be of great importance especially in patients with CKD. As a pilot study of an animal model, Moe et al. (11) showed lower bioavailability of phosphorus in rats that had CKD and were fed grain-based chow compared with those that were fed casein-based chow with comparable contents of protein and phosphorus. In this issue of CJASN, they further demonstrated the decreased bioavailability of phosphorus from a vegetarian source than from a meat source in patients with stage 3/4 CKD and normal levels of serum phosphorus (12). In this crossover trial, which compared the effects of 1 week of vegetarian and meat diets with equivalent phosphorus content on mineral metabolism, Moe et al. found lower serum phosphorus levels, a trend toward decreased urine 24-h phosphorus excretion, and significantly decreased FGF23 levels in the vegetarian diet group compared with the meat diet group. Although more precise effects of phytate on absorption of other nutrients including calcium need to be clarified in the future, these observations will certainly have an effect on the new strategies for diet therapy in patients with CKD.

Despite its beneficial effects on the control of serum phosphorus, higher risk for malnutrition has recently been recognized in severe dietary protein restriction (13). By considering dietary phosphorus sources in more detail, it may become possible to control actual phosphorus load without the risk for malnutrition (14). Furthermore, ethnic differences in CKD progression and its manifestation may possibly be explained by the differences in food sources (7,10). For this reason, information of phosphorus bioavailability needs to be provided for food frequency questionnaires, food tables, and nutritional database, in addition to the contents of phosphorus, phosphorus–protein ratio (7), and food additives. Only after such information is routinely available for nutritional assessments will it become possible to manage actual phosphorus burden adequately while simultaneously maintaining protein intake in patients with CKD. Whether such management strategy provides survival benefit to dialysis patients as well as predialysis patients with CKD and whether measuring FGF23 levels is useful to guide phosphorus management in this situation (15) are interesting and worthy of further investigation.

Disclosures

None.

Footnotes

  • Published online ahead of print. Publication date available at www.cjasn.org.

  • See related article, “Vegetarian Compared with Meat Dietary Protein Source and Phosphorus Homeostasis in Chronic Kidney Disease,” on pages 257–264.

  • Copyright © 2011 by the American Society of Nephrology

References

  1. ↵
    1. Block GA,
    2. Klassen PS,
    3. Lazarus JM,
    4. Ofshun N,
    5. Lowrie EG,
    6. Chertow GM
    : Mineral metabolism, mortality, and morbidity in maintenance hemodialysis. J Am Soc Nephrol 15: 2208–2218, 2004
    OpenUrlAbstract/FREE Full Text
  2. ↵
    1. Yi H,
    2. Fukagawa M,
    3. Yamato H,
    4. Kumagai M,
    5. Watanabe T,
    6. Kurokawa K
    : Prevention of enhanced parathyroid hormone secretion, synthesis and hyperplasia by mild dietary phosphorus restriction in early chronic renal failure in rats: Possible direct role of phosphorus. Nephron 70: 242–248, 1995
    OpenUrlCrossRefPubMed
  3. ↵
    1. Oliveira RB,
    2. Cancela AL,
    3. Graciolli FG,
    4. Dos Reis LM,
    5. Draibe SA,
    6. Cuppari L,
    7. Carvalho AB,
    8. Jorgetti V,
    9. Canziani ME,
    10. Moyses RM
    : Early control of PTH and FGF23 in normophosphatemic CKD patients: A new target in CKD-MBD therapy? Clin J Am Soc Nephrol 5: 286–291, 2010
    OpenUrlAbstract/FREE Full Text
  4. ↵
    1. Hasegawa H,
    2. Nagano N,
    3. Urakawa I,
    4. Yamazaki Y,
    5. Iijima K,
    6. Fujita T,
    7. Yamashita T,
    8. Fukumoto S,
    9. Shimada T
    : Direct evidence for a causative role of FGF23 in the abnormal renal phosphate handling and vitamin D metabolism in rats with early stage of chronic kidney disease. Kidney Int 78: 975–980, 2010
    OpenUrlCrossRefPubMed
  5. ↵
    1. Katai K,
    2. Tanaka H,
    3. Tatsumi S,
    4. Fukunaga Y,
    5. Genjida K,
    6. Morita K,
    7. Kuboyama N,
    8. Suzuki T,
    9. Akiba T,
    10. Miyamoto K,
    11. Takeda E
    : Nicotinamide inhibits sodium-dependent phosphate cotransport activity in rat small intestine. Nephrol Dial Transplant 14: 1195–1201, 1999
    OpenUrlCrossRefPubMed
  6. ↵
    1. Kazama JJ
    : Oral phosphate binders: History and prospects. Bone 45[Suppl 2]: S8–S12, 2009
    OpenUrlCrossRefPubMed
  7. ↵
    1. Kalanter-Zadeh K,
    2. Gutekunst L,
    3. Mehrotra R,
    4. Kovesdy C,
    5. Bross R,
    6. Shinaberger CS,
    7. Noori N,
    8. Hirschberg R,
    9. Benner D,
    10. Nissenson AR,
    11. Kopple J
    : Understanding sources of dietary phosphorus in the treatment of patients with chronic kidney disease. Clin J Am Soc Nephrol 5: 519–530, 2010
    OpenUrlAbstract/FREE Full Text
  8. ↵
    1. Sullivan C,
    2. Sayre SS,
    3. Leon JB,
    4. Machekano R,
    5. Love TE,
    6. Porter D,
    7. Marquisha MA,
    8. Sehgal AR
    : Effect of food additives on hyperphosphatemia among patients with end-stage renal disease. JAMA 301: 629–635, 2009
    OpenUrlCrossRefPubMed
  9. ↵
    1. Sherman RA,
    2. Mehta O
    : Dietary phosphorus restriction in dialysis patients: Potential impact of processed meat, poultry, and fish products as protein sources. Am J Kidney Dis 54: 18–23, 2009
    OpenUrlCrossRefPubMed
  10. ↵
    1. Schlemmer U,
    2. Frolich W,
    3. Prieto RM,
    4. Grases F
    : Phytate in food and significance for humans: Food sources, intake, processing, bioavailability, protective role and analysis. Mol Nutr Food Res 53: S330–S375, 2009
    OpenUrlCrossRefPubMed
  11. ↵
    1. Moe SM,
    2. Chen NX,
    3. Seifert MF,
    4. Sinders RM,
    5. Duan D,
    6. Chen X,
    7. Liang Y,
    8. Radcliff JS,
    9. White KE,
    10. Gattone VH 2nd.
    : A rat model of chronic kidney disease-mineral bone disorder. Kidney Int 75: 176–184, 2009
    OpenUrlCrossRefPubMed
  12. ↵
    1. Moe SM,
    2. Zidehsarai MP,
    3. Chambers MA,
    4. Jackman LA,
    5. Radcliff JS,
    6. Trevino LL,
    7. Donahue SE,
    8. Asplin JR
    : Vegetarian compared with meat dietary protein source and phosphorus homeostasis in chronic kidney disease. Clin J Am Soc Nephrol 6: 257–264, 2011
    OpenUrlAbstract/FREE Full Text
  13. ↵
    1. Shinaberger CS,
    2. Greenland S,
    3. Kopple JD,
    4. Van Wyck D,
    5. Mehrotra R,
    6. Kovesdy CP,
    7. Kalanter-Zadeh K
    : Is controlling phosphorus by decreasing dietary protein intake beneficial or harmful in persons with chronic kidney disease? Am J Clin Nutr 88: 1511–1518, 2008
    OpenUrlAbstract/FREE Full Text
  14. ↵
    1. Mathewson AM,
    2. Fouque D,
    3. Toft AJ
    : Dietary phosphate assessment in dialysis patients. J Ren Nutr 20: 351–358, 2010
    OpenUrlCrossRefPubMed
  15. ↵
    1. Koiwa F,
    2. Kazama JJ,
    3. Tokumoto A,
    4. Onoda N,
    5. Kato H,
    6. Okada T,
    7. Nii-Kono T,
    8. Fukagawa M,
    9. Shigematsu T
    : Sevelamer hydrochloride and calcium carbonate reduce serum FGF23 levels in dialysis patients. Ther Apher Dial 9: 328–330, 2005
    OpenUrlCrossRefPubMed
PreviousNext
Back to top

In this issue

Clinical Journal of the American Society of Nephrology: 6 (2)
Clinical Journal of the American Society of Nephrology
Vol. 6, Issue 2
1 Feb 2011
  • Table of Contents
  • Table of Contents (PDF)
  • Index by author
View Selected Citations (0)
Print
Download PDF
Sign up for Alerts
Email Article
Thank you for your help in sharing the high-quality science in CJASN.
Enter multiple addresses on separate lines or separate them with commas.
Source Matters: From Phosphorus Load to Bioavailability
(Your Name) has sent you a message from American Society of Nephrology
(Your Name) thought you would like to see the American Society of Nephrology web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Source Matters: From Phosphorus Load to Bioavailability
Masafumi Fukagawa, Hirotaka Komaba, Ken-ichi Miyamoto
CJASN Feb 2011, 6 (2) 239-240; DOI: 10.2215/CJN.11051210

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Request Permissions
Share
Source Matters: From Phosphorus Load to Bioavailability
Masafumi Fukagawa, Hirotaka Komaba, Ken-ichi Miyamoto
CJASN Feb 2011, 6 (2) 239-240; DOI: 10.2215/CJN.11051210
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like

Jump to section

  • Article
    • Disclosures
    • Footnotes
    • References
  • Info & Metrics
  • View PDF

More in this TOC Section

  • Steroid Regimen for Children with Nephrotic Syndrome Relapse
  • Mind the Gap
  • Opportunities for Improvement in Quality of Care of PD-Related Peritonitis in Children
Show more Editorials

Cited By...

  • Assessing the Health Impact of Phosphorus in the Food Supply: Issues and Considerations
  • The Production of p-Cresol Sulfate and Indoxyl Sulfate in Vegetarians Versus Omnivores
  • Google Scholar

Similar Articles

Related Articles

  • Vegetarian Compared with Meat Dietary Protein Source and Phosphorus Homeostasis in Chronic Kidney Disease
  • PubMed
  • Google Scholar

Articles

  • Current Issue
  • Early Access
  • Subject Collections
  • Article Archive
  • ASN Meeting Abstracts

Information for Authors

  • Submit a Manuscript
  • Trainee of the Year
  • Author Resources
  • ASN Journal Policies
  • Reuse/Reprint Policy

About

  • CJASN
  • ASN
  • ASN Journals
  • ASN Kidney News

Journal Information

  • About CJASN
  • CJASN Email Alerts
  • CJASN Key Impact Information
  • CJASN Podcasts
  • CJASN RSS Feeds
  • Editorial Board

More Information

  • Advertise
  • ASN Podcasts
  • ASN Publications
  • Become an ASN Member
  • Feedback
  • Follow on Twitter
  • Password/Email Address Changes
  • Subscribe

© 2021 American Society of Nephrology

Print ISSN - 1555-9041 Online ISSN - 1555-905X

Powered by HighWire