The circadian rhythm of calcium and bone homeostasis in Maasai
Am J Hum Biol. 2022 Apr 28;e23756. doi: 10.1002/ajhb.23756
Anne Schou 1 2, Niklas Rye Jørgensen 3 4, Venance Phillip Maro 5, Kajiru Kilonzo 5, Kaushik Ramaiya 6, Joseph Sironga 5 7, Andreas Kryger Jensen 2 4, Dirk Lund Christensen 2 4, Peter Schwarz 1 4
Objectives: Ethnic groups differ in prevalence of calcium-related diseases. Differences in the physiology and the endogenous circadian rhythm (CR) of calcium and bone homeostasis may play a role. Thus, we aimed to investigate details of CR pattern in calcium and bone homeostasis in East African Maasai.
Methods: Ten clinically healthy adult Maasai men and women from Tanzania were examined. Blood samples were collected every 2nd hour for 24 h. Serum levels of total calcium, albumin, parathyroid hormone (PTH), 25(OH)D, creatinine, C-terminal telopeptide (CTX), bone-specific alkaline phosphatase (BSAP), procollagen type 1 N-terminal propeptide (P1NP), and osteocalcin were measured. Circadian patterns were derived from graphic curves of medians, and rhythmicity was assessed with Fourier analysis.
Results: PTH-levels varied over the 24 h exhibiting a bimodal pattern. Nadir level corresponded to 65% of total 24-h mean. CTX and P1NP showed 24-h variations with a morning nadir and nocturnal peak with nadir levels corresponding to 23% and 79% of the 24-h mean, respectively. Albumin-corrected calcium level was held in a narrow range and alterations were corresponding to alterations in PTH. There was no distinct pattern in 24-h variations of 25(OH)D, creatinine, osteocalcin, or BSAP.
Conclusions: All participants showed pronounced 24-h variations in PTH and bone turnover markers CTX and P1NP. These findings support that Maasai participants included in this study have typical patterns of CR in calcium and bone homeostasis consistent with findings from other ethnic populations.
Download the PDF from VitaminDWiki
From PDF
- "The traditional Maasai diet to a large degree consists of milk and milk products with some studies suggesting that these account for ~20% of the daily energy intake"
- "Eighteen individuals were initially enrolled in the study following 12 h of overnight fasting"
- "All participants received food as close to their typical daily diet as possible."
- They were indoors in a hotel during the experiment - not exposed to the sun
- Without access to the sun it seems reasonable that there was no circadian changes in Vitamin D levels
- No indication if the experiment was conducted in the dry or wet season
VitaminDWiki pages with PTH in title (32 as of April 2022)
This list is automatically updated
Items found: 36
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Modified |
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Calcium, PTH etc. levels vary by about 30% during the day – Aug 2024 |
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21 Sep, 2024 |
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3 Cancers have higher mortality if high PTH (which can be lowered by Vitamin D) - Aug 2024 |
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15 Aug, 2024 |
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Vitamin D dosing varies with genes, PTH, Mg, Vit K, etc – video and transcript Sept 2022 |
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29 Dec, 2022 |
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PTH and Vitamin D - many studies |
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29 Dec, 2022 |
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Maasai have PTH and bone resorption (CTX) circadian rhythms – April 2022 |
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29 Apr, 2022 |
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PTH failed to decrease with Vitamin D if overweight and had low Magnesium – Aug 2019 |
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04 Mar, 2022 |
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Based on PTH response, obese adolescents may not need and much vitamin D as non-obese (12 ng vs 16.5 ng) – June 2021 |
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12 Jun, 2021 |
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High PTH plus low Vitamin D is not good (5X more likely for COPD to need hospital) – April 2021 |
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25 Apr, 2021 |
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Increased Colorectal cancer risk if Vitamin D does not lower PTH (Vit D not getting to cells) – Nov 2020 |
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06 Nov, 2020 |
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ICU death rate reduced 3X when a vitamin D injection changed the PTH – Nov 2015 |
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06 Jun, 2020 |
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Worse diabetic vision is associated with low vitamin D or high PTH - Nov 2012 |
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07 Jan, 2020 |
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Hip fractures worse if both high PTH and low Vitamin D – Jan 2019 |
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01 Feb, 2019 |
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Interview of Dr. Coimbra: MS, Autoimmune, Vitamin D, B2, Ca, Mg, PTH etc. – perhaps 2018 |
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02 Dec, 2018 |
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Heart Failure is predicted by PTH (but vitamin D both prevents and treats HF) – Jan 2018 |
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31 Mar, 2018 |
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Coronary Heart Disease 57 percent more likely if poor Vitamin D Binding Protein with high PTH – Nov 2017 |
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08 Nov, 2017 |
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Ischemic Stroke risk best predicted by Vitamin D, including PTH improves the prediction – Feb 2017 |
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02 Mar, 2017 |
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Critically ill injected with 300,000 IU of vitamin D, 3X more likely to die if PTH did not respond - RCT July 2015 |
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22 Jan, 2017 |
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3000 IU of vitamin D minimum to reduce parathyroid hormone (PTH) – meta-analysis Sept 2015 |
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10 Dec, 2016 |
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Need 40 ng of vitamin D to have proper PTH levels – May 2011 |
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29 Mar, 2016 |
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PTH boosts immune response when vitamin D levels are low – May 2012 |
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29 Mar, 2016 |
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PTH does not plateau with increasing vitamin D, but does decrease with patient age – Aug 2012 |
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29 Mar, 2016 |
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Hypothesis Vitamin D receptor controls PTH without needing Vitamin D – Aug 2015 |
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01 Sep, 2015 |
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Knee Osteoarthritis 3.2X more likely to get worse if low Vitamin D and high PTH – Dec 2014 |
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23 Feb, 2015 |
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PTH reduced 3.5 pmol by vitamin D intervention which added 22 ng – meta-analysis June 2014 |
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01 Jan, 2015 |
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Diabetes after giving birth was associated with low vitamin D combined with high PTH – May 2014 |
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31 May, 2014 |
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ICU reduces Vitamin D levels, deregulates PTH - Sept 2013 |
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28 Sep, 2013 |
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Almost 3X more likely to get preeclampsia if low vitamin D and high PTH– July 2013 |
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15 Sep, 2013 |
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Vitamin D deficiency for children’s bones is 14ng, based on PTH analysis – Sept 2013 |
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09 Sep, 2013 |
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PTH needs vitamin D level higher than 13 ng – Cohort June 2010 |
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09 Sep, 2013 |
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Children have PTH problems when vitamin D is less than 15 ng – Nov 2011 |
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09 Sep, 2013 |
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Hypothesis: Not vitamin D deficient if have normal PTH and BMD – May 2013 |
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01 Jun, 2013 |
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1000 IU of vitamin D reduced child PTH, but did not increase Calcium – RCT Jan 2013 |
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03 Jan, 2013 |
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Chronic kidney disease and PTH – Calcium – Phosphate – Vitamin D – April 2011 |
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23 May, 2012 |
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20 ng of vitamin D is enough for African American PTH – Dec 2011 |
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09 Mar, 2012 |
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Africans in Europe might only need 19 ng of vitamin D – estimated from PTH July 2011 |
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09 Mar, 2012 |
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Blacks may need less vitamin D than whites – PTH Aug 2010 |
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23 Dec, 2011 |