Hostname: page-component-6766d58669-r8qmj Total loading time: 0 Render date: 2026-05-23T01:39:34.844Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of a 12 week low carbohydrate ketogenic diet versus a high carbohydrate diet on blood count indicators of iron status in male endurance athletes

Published online by Cambridge University Press:  29 September 2017

F. McSwiney ,
B. Wardrop ,
J. Volek  and
L. Doyle
F. McSwiney
Affiliation:
Department of Health, Sport and Exercise Science, Waterford Institute of Technology, Cork Road, Waterford
B. Wardrop
Affiliation:
Department of Health, Sport and Exercise Science, Waterford Institute of Technology, Cork Road, Waterford
J. Volek
Affiliation:
Kinesiology Program, Department of Human Sciences, The Ohio State University, Columbus, Ohio, USA
L. Doyle
Affiliation:
Department of Health, Sport and Exercise Science, Waterford Institute of Technology, Cork Road, Waterford
Rights & Permissions [Opens in a new window]

Abstract

An abstract is not available for this content. As you have access to this content, full HTML content is provided on this page. A PDF of this content is also available in through the ‘Save PDF’ action button.

Low carbohydrate ketogenic diets (LCKD) where carbohydrate intake is <50 g/d have become popular is many populations, including endurance athletes( Reference Volek, Noakes and Phinney 1 ). The complete effect of this diet on nutrient absorption and its potential to influence health has not been fully uncovered( Reference Paoli, Rubini and Volek 2 ). A 14 day ketogenic diet in females demonstrated no effect on RBC, Hb or Hct levels in healthy females( Reference Nazarewicz, Ziolkowski and Vaccaro 3 ), but longer duration research in an athletic population is lacking. The aim of the current research is to examine the effect of a LCKD versus a high carbohydrate diet, on blood count indicators of iron status in endurance athletes.

Following ethical approval 19 participants selected into a high carbohydrate (HC) (65 % kcal CHO, 20 % kcal fat, 14 % kcal protein) or LCKD (>75 % kcal fat, 10–15 % kcal protein and <50 g/d CHO) group for 12 weeks. Participants also completed an endurance training protocol during the trial. Whole blood samples were analysed using the haematology analyser before and after selection into each dietary group. RM ANOVA was used to assess changes in indicators of iron status in participants over time. Paired t-tests assessed changed within group over time.

RBC – red blood cell; Hb – haemoglobin; Hct – haematocrit; MCV – mean corpuscular volume; MCH – mean corpuscular haemoglobin; MCHC – mean corpuscular haemoglobin concentration; red cell distribution width.

* Significant difference at P < 0·05; a Significant difference within group over time at P < 0·05.

RBC, Hb, and Hct significantly decreased over time. Within group Hct decreased between weeks 1 and 12 in the HC participants and Hb, MCH and MCHC decreased within the LCKD participants.

Endurance training has been associated with increased plasma volume with exercise induced inflammation also implicated as a possible cause for iron deficiency in athletes( Reference Hinton 4 ). It is possible the endurance training added during this trial had a similar effect on iron status within these participants. However it does not explain the difference in Hb, MCH and MCHC between HC and LCKD participants. Due to the effect iron status has on oxygen transport to muscle, further research is warranted to investigate the effect of a ketogenic diet on iron status in endurance athletes.

References

1. Volek, JS, Noakes, T & Phinney, SD (2015) Eur J Sp Sci 15, 13–20.CrossRefGoogle Scholar
2. Paoli, A, Rubini, A, Volek, JS et al. (2013) Eur J Clin Nutr 67, 789–796.Google Scholar
3. Nazarewicz, RR, Ziolkowski, W, Vaccaro, PS et al. (2007) Rejuvenation Res 10, 435–439.CrossRefGoogle Scholar
4. Hinton, PS (2014) Appl Physiol Nutr Metab 39, 1012–1018.CrossRefGoogle Scholar