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Can Improving the Nutritional Content of Bread Enhance Cognition? Cognitive Outcomes from a Randomized Controlled Trial

  • Naomi White
  • Phoebe Naldoza-Drake
  • Katherine Black
  • Luke Scullion
  • Liana MachadoEmail author
Original Research
  • 11 Downloads

Abstract

Past research indicates that dietary alterations involving increases in nuts or beetroot, or decreases in salt, may have the potential to enhance cognitive functioning. The current study reports cognitive outcomes from a 12-week randomized controlled parallel intervention trial designed to evaluate the effectiveness of manipulating these ingredients in a dietary staple, bread. Participants were recruited from Dunedin, New Zealand, between February 2015 and March 2017. Initial inclusion criteria required at least one indicator of metabolic syndrome and daily consumption of at least six slices of bread, but these criteria were relaxed 6 months into the study due to recruitment difficulties. In total, 196 participants were randomized (using minimization by age group, sex, and body mass index) to consume one of four breads (hazelnut, beetroot, low salt, or a control white bread). Participants completed a computerized cognitive test battery and physiological testing at four points during the intervention. Analyses focused on 102 participants (aged 18–73 years) who finished the intervention and completed pre- and post-intervention cognitive testing. Participants who consumed the experimental breads showed no evidence of cognitive improvement relative to the control group. Furthermore, the expected physiological changes did not occur, and participants reported poor compliance. Our findings suggest that participants may have changed their eating habits during the intervention period such that they consumed less bread and ingested other counteracting nutrients, rendering the intervention ineffective. Insight from this study can be used to guide the design of future dietary interventions.

Keywords

Cognitive performance Dietary intervention Salt Beetroot Nuts 

Notes

Acknowledgments

The authors thank Georgia Best, Kirstin Bierre, Georgia Cowan, Stephanie Glover, Chris Gorman, Grace Killmer, Saejung Oh, Laura Thompson, Scott van Heerden, and the Human Nutrition team for their assistance with this project.

Funding Information

This research was supported by a Health Research Council of New Zealand Emerging Researcher First Grant awarded to Katherine Black (#14/581), and a Neurological Foundation of New Zealand Small Project Grant (#1537-SPG) awarded to Liana Machado.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

41465_2019_149_MOESM1_ESM.docx (16 kb)
Table S1 (DOCX 16 kb)

References

  1. Afsar, B. (2013). The relationship between cognitive function, depressive behaviour and sleep quality with 24-h urinary sodium excretion in patients with essential hypertension. High Blood Pressure & Cardiovascular Prevention, 20(1), 19–24.  https://doi.org/10.1007/s40292-013-0002-7.CrossRefGoogle Scholar
  2. Alfaro, F. J., Gavrieli, A., Saade-Lemus, P., Lioutas, V. A., Upadhyay, J., & Novak, V. (2018). White matter microstructure and cognitive decline in metabolic syndrome: a review of diffusion tensor imaging. Metabolism: Clinical and Experimental, 78, 52–68.  https://doi.org/10.1016/j.metabol.2017.08.009.CrossRefGoogle Scholar
  3. Austin, B. P., Nair, V. A., Meier, T. B., Xu, G., Rowley, H. A., Carlsson, C. M., et al. (2011). Effects of hypoperfusion in Alzheimer’s disease. Journal of Alzheimer’s Disease, 26(Suppl 3), 123–133.  https://doi.org/10.3233/JAD-2011-0010.CrossRefPubMedPubMedCentralGoogle Scholar
  4. Bahaeddin, Z., Yans, A., Khodagholi, F., Hajimehdipoor, H., & Sahranavard, S. (2017). Hazelnut and neuroprotection: improved memory and hindered anxiety in response to intra-hippocampal Abeta injection. Nutritional Neuroscience, 20(6), 317–326.  https://doi.org/10.1080/1028415X.2015.1126954.CrossRefPubMedGoogle Scholar
  5. Barbour, J. A., Howe, P. R., Buckley, J. D., Bryan, J., & Coates, A. M. (2014). Nut consumption for vascular health and cognitive function. Nutrition Research Reviews, 27(1), 131–158.  https://doi.org/10.1017/S0954422414000079.CrossRefPubMedGoogle Scholar
  6. Barnham, K. J., Masters, C. L., & Bush, A. I. (2004). Neurodegenerative diseases and oxidative stress. Nature Reviews Drug Discovery, 3(3), 205–214.  https://doi.org/10.1038/nrd1330.CrossRefPubMedGoogle Scholar
  7. Bolhuis, D. P., Temme, E. H., Koeman, F. T., Noort, M. W., Kremer, S., & Janssen, A. M. (2011). A salt reduction of 50% in bread does not decrease bread consumption or increase sodium intake by the choice of sandwich fillings. Journal of Nutrition, 141(12), 2249–2255.  https://doi.org/10.3945/jn.111.141366.CrossRefPubMedGoogle Scholar
  8. Brainard, D. H. (1997). The psychophysics toolbox. Spatial Vision, 10(4), 433–436.  https://doi.org/10.1163/156856897X00357.CrossRefPubMedPubMedCentralGoogle Scholar
  9. Chisholm, A., Mc Auley, K., Mann, J., Williams, S., & Skeaff, M. (2005). Cholesterol lowering effects of nuts compared with a canola oil enriched cereal of similar fat composition. Nutrition, Metabolism, and Cardiovascular Diseases, 15(4), 284–292.  https://doi.org/10.1016/j.numecd.2005.01.006.CrossRefPubMedGoogle Scholar
  10. Chugh, G., Asghar, M., Patki, G., Bohat, R., Jafri, F., Allam, F., et al. (2013). A high-salt diet further impairs age-associated declines in cognitive, behavioral, and cardiovascular functions in male Fischer brown Norway rats. Journal of Nutrition, 143(9), 1406–1413.  https://doi.org/10.3945/jn.113.177980.CrossRefPubMedGoogle Scholar
  11. Corsi, P. M. (1972). Human memory and the medial temporal region of the brain. Dissertation Abstracts International, 34, 819B.Google Scholar
  12. Cutler, J. A., Follmann, D., & Allender, P. S. (1997). Randomized trials of sodium reduction: An overview. American Journal of Clinical Nutrition, 65(2 Suppl), 643S–651S.  https://doi.org/10.1093/ajcn/65.2.643S.CrossRefPubMedGoogle Scholar
  13. Devi, A., Chisholm, A., Gray, A., Tey, S. L., Williamson-Poutama, D., Cameron, S. L., & Brown, R. C. (2015). Nut-enriched bread is an effective and acceptable vehicle to improve regular nut consumption. European Journal of Nutrition.  https://doi.org/10.1007/s00394-015-1038-3.CrossRefGoogle Scholar
  14. Fiocco, A. J., Shatenstein, B., Ferland, G., Payette, H., Belleville, S., Kergoat, M. J., et al. (2012). Sodium intake and physical activity impact cognitive maintenance in older adults: The NuAge study. Neurobiology of Aging, 33(4), 829 e821–829 e828.  https://doi.org/10.1016/j.neurobiolaging.2011.07.004.CrossRefGoogle Scholar
  15. Folstein, M. F., Folstein, S. E., & McHugh, P. R. (1975). “mini-mental state”. A practical method for grading the cognitive state of patients for the clinician. Journal of Psychiatric Research, 12(3), 189–198.  https://doi.org/10.1016/0022-3956(75)90026-6.CrossRefPubMedGoogle Scholar
  16. Forsyth, B., Machado, L., Jowett, T., Jakobi, H., Garbe, K., Winter, H., & Glue, P. (2016). Effects of low dose ibogaine on subjective mood state and psychological performance. Journal of Ethnopharmacology, 189, 10–13.  https://doi.org/10.1016/j.jep.2016.05.022.CrossRefPubMedGoogle Scholar
  17. Gilchrist, M., Winyard, P. G., Fulford, J., Anning, C., Shore, A. C., & Benjamin, N. (2014). Dietary nitrate supplementation improves reaction time in type 2 diabetes: development and application of a novel nitrate-depleted beetroot juice placebo. Nitric Oxide, 40, 67–74.  https://doi.org/10.1016/j.niox.2014.05.003.CrossRefPubMedGoogle Scholar
  18. Gomez-Pinilla, F. (2008). Brain foods: the effects of nutrients on brain function. Nature Reviews: Neuroscience, 9(7), 568–578.  https://doi.org/10.1038/nrn2421.CrossRefPubMedGoogle Scholar
  19. Haring, B., Wu, C., Coker, L. H., Seth, A., Snetselaar, L., Manson, J. E., et al. (2016). Hypertension, dietary sodium, and cognitive decline: results from the Women’s Health Initiative memory study. American Journal of Hypertension, 29(2), 202–216.  https://doi.org/10.1093/ajh/hpv081.CrossRefPubMedGoogle Scholar
  20. He, F. J., & MacGregor, G. A. (2002). Effect of modest salt reduction on blood pressure: a meta-analysis of randomized trials. Implications for public health. Journal of Human Hypertension, 16(11), 761–770.  https://doi.org/10.1038/sj.jhh.1001459.CrossRefPubMedGoogle Scholar
  21. Hobbs, D. A., Kaffa, N., George, T. W., Methven, L., & Lovegrove, J. A. (2012). Blood pressure-lowering effects of beetroot juice and novel beetroot-enriched bread products in normotensive male subjects. British Journal of Nutrition, 108(11), 2066–2074.  https://doi.org/10.1017/S0007114512000190.CrossRefPubMedGoogle Scholar
  22. Hobbs, D. A., Goulding, M. G., Nguyen, A., Malaver, T., Walker, C. F., George, T. W., et al. (2013). Acute ingestion of beetroot bread increases endothelium-independent vasodilation and lowers diastolic blood pressure in healthy men: a randomized controlled trial. Journal of Nutrition, 143(9), 1399–1405.  https://doi.org/10.3945/jn.113.175778.CrossRefPubMedGoogle Scholar
  23. Iadecola, C., Yaffe, K., Biller, J., Bratzke, L. C., Faraci, F. M., Gorelick, P. B., et al. (2016). Impact of hypertension on cognitive function: a scientific statement from the American Heart Association. Hypertension, 68(6), e67–e94.  https://doi.org/10.1161/HYP.0000000000000053.CrossRefPubMedPubMedCentralGoogle Scholar
  24. Kelly, J., Fulford, J., Vanhatalo, A., Blackwell, J. R., French, O., Bailey, S. J., et al. (2013). Effects of short-term dietary nitrate supplementation on blood pressure, O2 uptake kinetics, and muscle and cognitive function in older adults. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 304(2), R73–R83.  https://doi.org/10.1152/ajpregu.00406.2012.CrossRefPubMedGoogle Scholar
  25. Kessels, R. P., van Zandvoort, M. J., Postma, A., Kappelle, L. J., & de Haan, E. H. (2000). The Corsi block-tapping task: standardization and normative data. Applied Neuropsychology, 7(4), 252–258.  https://doi.org/10.1207/S15324826AN0704_8.CrossRefPubMedGoogle Scholar
  26. Lidder, S., & Webb, A. J. (2013). Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. British Journal of Clinical Pharmacology, 75(3), 677–696.  https://doi.org/10.1111/j.1365-2125.2012.04420.x.CrossRefPubMedPubMedCentralGoogle Scholar
  27. Liu, Y. Z., Chen, J. K., Li, Z. P., Zhao, T., Ni, M., Li, D. J., et al. (2014). High-salt diet enhances hippocampal oxidative stress and cognitive impairment in mice. Neurobiology of Learning and Memory, 114, 10–15.  https://doi.org/10.1016/j.nlm.2014.04.010.CrossRefPubMedGoogle Scholar
  28. McMahon, E., Clarke, R., Jaenke, R., & Brimblecombe, J. (2016). Detection of 12.5% and 25% salt reduction in bread in a remote indigenous Australian community. Nutrients, 8(3), 169.  https://doi.org/10.3390/nu8030169.CrossRefPubMedPubMedCentralGoogle Scholar
  29. Nooyens, A. C., Bueno-de-Mesquita, H. B., van Boxtel, M. P., van Gelder, B. M., Verhagen, H., & Verschuren, W. M. (2011). Fruit and vegetable intake and cognitive decline in middle-aged men and women: the Doetinchem cohort study. British Journal of Nutrition, 106(5), 752–761.  https://doi.org/10.1017/S0007114511001024.CrossRefPubMedGoogle Scholar
  30. Ozemek, C., Phillips, S. A., Popovic, D., Laddu-Patel, D., Fancher, I. S., Arena, R., & Lavie, C. J. (2017). Nonpharmacologic management of hypertension: a multidisciplinary approach. Current Opinion in Cardiology, 32(4), 381–388.  https://doi.org/10.1097/HCO.0000000000000406.CrossRefPubMedGoogle Scholar
  31. Pelli, D. G. (1997). The VideoToolbox software for visual psychophysics: transforming numbers into movies. Spatial Vision, 10(4), 437–442.  https://doi.org/10.1163/156856897X00366.CrossRefGoogle Scholar
  32. Poulet, R., Gentile, M. T., Vecchione, C., Distaso, M., Aretini, A., Fratta, L., et al. (2006). Acute hypertension induces oxidative stress in brain tissues. Journal of Cerebral Blood Flow and Metabolism, 26(2), 253–262.  https://doi.org/10.1038/sj.jcbfm.9600188.CrossRefPubMedGoogle Scholar
  33. Poulose, S. M., Miller, M. G., & Shukitt-Hale, B. (2014). Role of walnuts in maintaining brain health with age. Journal of Nutrition, 144(4 Suppl), 561S–566S.  https://doi.org/10.3945/jn.113.184838.CrossRefPubMedGoogle Scholar
  34. Presley, T. D., Morgan, A. R., Bechtold, E., Clodfelter, W., Dove, R. W., Jennings, J. M., et al. (2011). Acute effect of a high nitrate diet on brain perfusion in older adults. Nitric Oxide, 24(1), 34–42.  https://doi.org/10.1016/j.niox.2010.10.002.CrossRefPubMedGoogle Scholar
  35. Pribis, P., & Shukitt-Hale, B. (2014). Cognition: the new frontier for nuts and berries. American Journal of Clinical Nutrition, 100(Supplement 1), 347S–352S.  https://doi.org/10.3945/ajcn.113.071506.CrossRefPubMedGoogle Scholar
  36. Pribis, P., Bailey, R. N., Russell, A. A., Kilsby, M. A., Hernandez, M., Craig, W. J., et al. (2012). Effects of walnut consumption on cognitive performance in young adults. British Journal of Nutrition, 107(9), 1393–1401.  https://doi.org/10.1017/S0007114511004302.CrossRefPubMedGoogle Scholar
  37. Siervo, M., Lara, J., Ogbonmwan, I., & Mathers, J. C. (2013). Inorganic nitrate and beetroot juice supplementation reduces blood pressure in adults: a systematic review and meta-analysis. Journal of Nutrition, 143(6), 818–826.  https://doi.org/10.3945/jn.112.170233.CrossRefPubMedGoogle Scholar
  38. Tanaka, T., Okamura, T., Miura, K., Kadowaki, T., Ueshima, H., Nakagawa, H., & Hashimoto, T. (2002). A simple method to estimate populational 24-h urinary sodium and potassium excretion using a casual urine specimen. Journal of Human Hypertension, 16(2), 97–103.  https://doi.org/10.1038/sj.jhh.1001307.CrossRefPubMedGoogle Scholar
  39. Tey, S. L., Brown, R. C., Chisholm, A. W., Delahunty, C. M., Gray, A. R., & Williams, S. M. (2011). Effects of different forms of hazelnuts on blood lipids and α-tocopherol concentrations in mildly hypercholesterolemic individuals. European Journal of Clinical Nutrition, 65(1), 117–124.  https://doi.org/10.1038/ejcn.2010.200.CrossRefPubMedGoogle Scholar
  40. Tey, S. L., Brown, R. C., & Chisholm, A. W. (2012). Nuts and heart health. National heart foundation of New Zealand evidence-based position statement on the relationship of nuts to heart health. Auckland: National Heart Foundation of New Zealand.Google Scholar
  41. Thompson, K. G., Turner, L., Prichard, J., Dodd, F., Kennedy, D. O., Haskell, C., et al. (2014). Influence of dietary nitrate supplementation on physiological and cognitive responses to incremental cycle exercise. Respiratory Physiology & Neurobiology, 193, 11–20.  https://doi.org/10.1016/j.resp.2013.12.015.CrossRefGoogle Scholar
  42. Thompson, C., Wylie, L. J., Fulford, J., Kelly, J., Black, M. I., McDonagh, S. T., et al. (2015). Dietary nitrate improves sprint performance and cognitive function during prolonged intermittent exercise. European Journal of Applied Physiology, 115(9), 1825–1834.  https://doi.org/10.1007/s00421-015-3166-0.CrossRefPubMedGoogle Scholar
  43. Thurnham, D. I., Smith, E., & Flora, P. S. (1988). Concurrent liquid-chromatographic assay of retinol, alpha-tocopherol, beta-carotene, alpha-carotene, lycopene, and beta-cryptoxanthin in plasma, with tocopherol acetate as internal standard. Clinical Chemistry, 34(2), 377–381.PubMedGoogle Scholar
  44. University of Otago and Ministry of Health. (2011). A focus on nutrition: Key findings of the 2008/09 New Zealand adult nutrition survey. Wellington: Ministry of Health Retrieved from http://www.health.govt.nz/system/files/documents/publications/a-focus-on-nutrition-v2.pdf.Google Scholar
  45. Webb, A. J., Patel, N., Loukogeorgakis, S., Okorie, M., Aboud, Z., Misra, S., et al. (2008). Acute blood pressure lowering, vasoprotective, and antiplatelet properties of dietary nitrate via bioconversion to nitrite. Hypertension, 51(3), 784–790.  https://doi.org/10.1161/HYPERTENSIONAHA.107.103523.CrossRefPubMedPubMedCentralGoogle Scholar
  46. Wengreen, H., Munger, R. G., Cutler, A., Quach, A., Bowles, A., Corcoran, C., et al. (2013). Prospective study of dietary approaches to stop hypertension- and Mediterranean-style dietary patterns and age-related cognitive change: the Cache County study on memory, health and aging. American Journal of Clinical Nutrition, 98(5), 1263–1271.  https://doi.org/10.3945/ajcn.112.051276.CrossRefPubMedGoogle Scholar
  47. White, N., Forsyth, B., Lee, A., & Machado, L. (2018). Repeated computerized cognitive testing: performance shifts and test-retest reliability in healthy young adults. Psychological Assessment, 30(4), 539–549.  https://doi.org/10.1037/pas0000503.CrossRefPubMedGoogle Scholar
  48. White, N., Flannery, L., McClintock, A., & Machado, L. (2019). Repeated computerized cognitive testing: performance shifts and test-retest reliability in healthy older adults. Journal of Clinical and Experimental Neuropsychology, 41(2), 179–191.  https://doi.org/10.1080/13803395.2018.1526888.CrossRefPubMedGoogle Scholar
  49. Wightman, E. L., Haskell-Ramsay, C. F., Thompson, K. G., Blackwell, J. R., Winyard, P. G., Forster, J., et al. (2015). Dietary nitrate modulates cerebral blood flow parameters and cognitive performance in humans: a double-blind, placebo-controlled, crossover investigation. Physiology and Behavior, 149, 149–158.  https://doi.org/10.1016/j.physbeh.2015.05.035.CrossRefPubMedGoogle Scholar
  50. Woodward, E., Eyles, H., & Ni Mhurchu, C. (2012). Key opportunities for sodium reduction in New Zealand processed foods. Australian and New Zealand Journal of Public Health, 36(1), 84–89.  https://doi.org/10.1111/j.1753-6405.2012.00829.x.CrossRefPubMedGoogle Scholar

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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Psychology and Brain Health Research CentreUniversity of OtagoDunedinNew Zealand
  2. 2.Brain Research New ZealandDunedinNew Zealand
  3. 3.Department of Human NutritionUniversity of OtagoDunedinNew Zealand

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