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Lucock MD. The evolution of human skin pigmentation: A changing medley of vitamins, genetic variability, and UV radiation during human expansion. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 180:252-271. [PMID: 36790744 PMCID: PMC10083917 DOI: 10.1002/ajpa.24564] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 05/19/2022] [Accepted: 05/25/2022] [Indexed: 04/12/2023]
Abstract
This review examines putative, yet likely critical evolutionary pressures contributing to human skin pigmentation and subsequently, depigmentation phenotypes. To achieve this, it provides a synthesis of ideas that frame contemporary thinking, without limiting the narrative to pigmentation genes alone. It examines how geography and hence the quality and quantity of UV exposure, pigmentation genes, diet-related genes, vitamins, anti-oxidant nutrients, and cultural practices intersect and interact to facilitate the evolution of human skin color. The article has a strong focus on the vitamin D-folate evolutionary model, with updates on the latest biophysical research findings to support this paradigm. This model is examined within a broad canvas that takes human expansion out of Africa and genetic architecture into account. A thorough discourse on the biology of melanization is provided (includes relationship to BH4 and DNA damage repair), with the relevance of this to the UV sensitivity of folate and UV photosynthesis of vitamin D explained in detail, including the relevance of these vitamins to reproductive success. It explores whether we might be able to predict vitamin-related gene polymorphisms that pivot metabolism to the prevailing UVR exposome within the vitamin D-folate evolutionary hypothesis context. This is discussed in terms of a primary adaptive phenotype (pigmentation/depigmentation), a secondary adaptive phenotype (flexible metabolic phenotype based on vitamin-related gene polymorphism profile), and a tertiary adaptive strategy (dietary anti-oxidants to support the secondary adaptive phenotype). Finally, alternative evolutionary models for pigmentation are discussed, as are challenges to future research in this area.
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Affiliation(s)
- Mark D. Lucock
- School of Environmental & Life SciencesUniversity of NewcastleOurimbahNew South WalesAustralia
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Lucock MD, Jones PR, Veysey M, Thota R, Garg M, Furst J, Martin C, Yates Z, Scarlett CJ, Jablonski NG, Chaplin G, Beckett EL. Biophysical evidence to support and extend the vitamin D-folate hypothesis as a paradigm for the evolution of human skin pigmentation. Am J Hum Biol 2021; 34:e23667. [PMID: 34418235 DOI: 10.1002/ajhb.23667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE To test the "vitamin D-folate hypothesis for the evolution of human skin pigmentation." METHODS Total ozone mapping spectrometer (TOMS) satellite data were used to examine surface UV-irradiance in a large (n = 649) Australian cross-sectional study population. Genetic analysis was used to score vitamin D- and folate-related gene polymorphisms (n = 22), along with two pigmentation gene variants (IRF4-rs12203592/HERC2-rs12913832). Red cell folate and vitamin D3 were measured by immunoassay and HPLC, respectively. RESULTS Ultraviolet radiation (UVR) and pigmentation genes interact to modify blood vitamin levels; Light skin IRF4-TT genotype has greatest folate loss while light skin HERC2-GG genotype has greatest vitamin D3 synthesis (reflected in both TOMS and seasonal data). UV-wavelength exhibits a dose-response relationship in folate loss within light skin IRF4-TT genotype (305 > 310 > 324 > 380 nm). Significant vitamin D3 photosynthesis only occurs within light skin HERC2-GG genotype, and is maximal at 305 nm. Three dietary antioxidants (vitamins C, E, and β-carotene) interact with UVR and pigmentation genes preventing oxidative loss of labile reduced folate vitamers, with greatest benefit in light skin IRF4-TT subjects. The putative photosensitiser, riboflavin, did not sensitize red cell folate to UVR and actually afforded protection. Four genes (5xSNPs) influenced blood vitamin levels when stratified by pigmentation genotype; MTHFR-rs1801133/rs1801131, TS-rs34489327, CYP24A-rs17216707, and VDR-ApaI-rs7975232. Lightest IRF4-TT/darkest HERC2-AA genotype combination (greatest folate loss/lowest vitamin D3 synthesis) has 0% occurrence. The opposing, commonest (39%) compound genotype (darkest IRF4-CC/lightest HERC2-GG) permits least folate loss and greatest synthesis of vitamin D3 . CONCLUSION New biophysical evidence supports the vitamin D-folate hypothesis for evolution of skin pigmentation.
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Affiliation(s)
- Mark D Lucock
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Patrice R Jones
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | | | - Rohith Thota
- Nutraceuticals Research Group, University of Newcastle, Callaghan, New South Wales, Australia.,Metabolism and Nutrition, Riddet Institute, Massey University, Palmerston North, New Zealand
| | - Manohar Garg
- Nutraceuticals Research Group, University of Newcastle, Callaghan, New South Wales, Australia
| | - John Furst
- Maths and Physical Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Charlotte Martin
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Zoe Yates
- Biomedical Sciences and Pharmacy, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Christopher J Scarlett
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
| | - Nina G Jablonski
- Anthropology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - George Chaplin
- Anthropology Department, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Emma L Beckett
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia
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Jablonski NG. The evolution of human skin pigmentation involved the interactions of genetic, environmental, and cultural variables. Pigment Cell Melanoma Res 2021; 34:707-729. [PMID: 33825328 PMCID: PMC8359960 DOI: 10.1111/pcmr.12976] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 12/12/2022]
Abstract
The primary biological role of human skin pigmentation is as a mediator of penetration of ultraviolet radiation (UVR) into the deep layers of skin and the cutaneous circulation. Since the origin of Homo sapiens, dark, protective constitutive pigmentation and strong tanning abilities have been favored under conditions of high UVR and represent the baseline condition for modern humans. The evolution of partly depigmented skin and variable tanning abilities has occurred multiple times in prehistory, as populations have dispersed into environments with lower and more seasonal UVR regimes, with unique complements of genes and cultural practices. The evolution of extremes of dark pigmentation and depigmentation has been rare and occurred only under conditions of extremely high or low environmental UVR, promoted by positive selection on variant pigmentation genes followed by limited gene flow. Over time, the evolution of human skin pigmentation has been influenced by the nature and course of human dispersals and modifications of cultural practices, which have modified the nature and actions of skin pigmentation genes. Throughout most of prehistory and history, the evolution of human skin pigmentation has been a contingent and non-deterministic process.
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Affiliation(s)
- Nina G. Jablonski
- Department of AnthropologyThe Pennsylvania State UniversityUniversity ParkPAUSA
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Lucock M. Vitamin-related phenotypic adaptation to exposomal factors: The folate-vitamin D-exposome triad. Mol Aspects Med 2021; 87:100944. [PMID: 33551238 DOI: 10.1016/j.mam.2021.100944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/02/2021] [Accepted: 01/25/2021] [Indexed: 12/16/2022]
Abstract
The biological role of two key vitamins, folic acid and vitamin D is so fundamental to life processes, it follows that their UV sensitivity, dietary abundance (both key exposomal factors) and variability in dependent genes will modify their functional efficacy, particularly in the context of maintaining the integrity and function of genome and epigenome. This article therefore examines folate and vitamin D-related phenotypic adaptation to environmental factors which vary across the human life cycle as well as over an evolutionary time-scale. Molecular mechanisms, key nutrigenomic factors, phenotypic maladaptation and evolutionary models are discussed.
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Affiliation(s)
- Mark Lucock
- School of Environmental & Life Sciences, University of Newcastle, PO Box 127, Brush Rd, Ourimbah, NSW, 2258, Australia.
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Risk evaluation of vitamin D insufficiency or deficiency in children using simple scores: The Healthy Growth Study. Nutr Res 2020; 88:19-27. [PMID: 33743321 DOI: 10.1016/j.nutres.2020.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 11/21/2022]
Abstract
Although identification of population groups at high risk for low vitamin D status is of public health importance,there are no risk prediction tools available for children in Southern Europe that can cover this need. The present study aimed to develop and validate 2 simple scores that evaluate the risk for vitamin D insufficiency or deficiency in children. A cross-sectional epidemiological study was conducted among 2280 schoolchildren (9--13-year-old) living in Greece. The total sample was randomly divided into 2 subsamples of 1524 and 756 children, used in the development and validation of the 2 scores, respectively. Multivariate logistic regression analyses were used to develop the 2 risk evaluation scores, while receiver operating characteristic curves were employed to identify the optimal "points of change" for each risk score, upon which vitamin D insufficiency and deficiency is diagnosed with the highest possible sensitivity and specificity. The components of the 2 risk evaluation scores included children's age, gender, region of residence, screen-time, body weight status, maternal education, and season. The increase in each score by 1 unit elevated the likelihood for vitamin D insufficiency and deficiency by 31% and 28%, respectively. The receiver operating characteristic curves showed that the optimal "points of change" for each risk score, upon which vitamin D insufficiency or deficiency is diagnosed with the highest possible sensitivity and specificity were 8.5 and 12.5, respectively. In conclusion, this study developed 2 simple scores that evaluate the risk for vitamin D insufficiency or deficiency in children living in Greece. However, more studies are required for these scores to be validated in other populations of children from different countries.
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Morgan B, Mant M, de la Cova C, Brickley MB. Osteoporosis, osteomalacia, and hip fracture: A case study from the Terry collection. INTERNATIONAL JOURNAL OF PALEOPATHOLOGY 2020; 30:17-21. [PMID: 32402820 DOI: 10.1016/j.ijpp.2020.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 02/27/2020] [Accepted: 03/21/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVE This case study describes a perimortem hip fracture in a documented individual from the Robert J. Terry Skeletal Collection. The purpose of this paper is to comprehend how co-occurring conditions contributed to fracture risk and to understand the effect of the injury on this individual. MATERIALS AND METHODS A 73-year-old female from the Terry Collection with a fracture of the left proximal femur was assessed macroscopically, and images were taken with a Keyence VHX-2000 digital microscope. Documentation concerning the individual's history and contemporary treatment of hip fractures was explored. RESULTS Assessment demonstrated impaction of fractured elements occurred as a result of the inferior displacement of the femoral head into the femoral neck. Eburnation and hinge fractures are present on the fracture margins. Bending deformities of the sacrum, sternum, and ribs indicate underlying osteomalacia. No evidence of surgical intervention was observed. CONCLUSIONS Both osteomalacia and osteoporosis contributed to overall fracture risk in this case, which demonstrates how complex underlying factors can interact to increase the probability of fracture, and influence post-fracture mortality. SIGNIFICANCE This report is the first case study, to date, of a healing hip fracture in which the circumstances of the fracture and the medical history of the individual are known. LIMITATIONS To fully investigate osteoporosis, bone mineral density for this individual should be compared with others in the collection. SUGGESTIONS FOR FURTHER RESEARCH The effect of co-occurring conditions on fracture risk should be explored in the wider Terry Collection, and in other skeletal collections.
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Affiliation(s)
- Brianne Morgan
- Department of Anthropology, McMaster University, Hamilton, ON L8S 4L9, Canada.
| | - Madeleine Mant
- Department of Archaeology, Memorial University, St. John's, NL A1B 3R6, Canada; Department of Anthropology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
| | - Carlina de la Cova
- Department of Anthropology, University of South Carolina, Columbia, SC 29208, USA.
| | - Megan B Brickley
- Department of Anthropology, McMaster University, Hamilton, ON L8S 4L9, Canada.
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Flegr J, Sýkorová K, Fiala V, Hlaváčová J, Bičíková M, Máčová L, Kaňková Š. Increased 25(OH)D3 level in redheaded people: Could redheadedness be an adaptation to temperate climate? Exp Dermatol 2020; 29:598-609. [DOI: 10.1111/exd.14119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/18/2020] [Accepted: 05/23/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Jaroslav Flegr
- Department of Philosophy and History of Sciences Faculty of Science Charles University Prague Czech Republic
| | - Kateřina Sýkorová
- Department of Philosophy and History of Sciences Faculty of Science Charles University Prague Czech Republic
| | - Vojtěch Fiala
- Department of Philosophy and History of Sciences Faculty of Science Charles University Prague Czech Republic
| | - Jana Hlaváčová
- Department of Philosophy and History of Sciences Faculty of Science Charles University Prague Czech Republic
| | | | | | - Šárka Kaňková
- Department of Philosophy and History of Sciences Faculty of Science Charles University Prague Czech Republic
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Harris AM, DeGiorgio M. Identifying and Classifying Shared Selective Sweeps from Multilocus Data. Genetics 2020; 215:143-171. [PMID: 32152048 PMCID: PMC7198270 DOI: 10.1534/genetics.120.303137] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/29/2020] [Indexed: 11/18/2022] Open
Abstract
Positive selection causes beneficial alleles to rise to high frequency, resulting in a selective sweep of the diversity surrounding the selected sites. Accordingly, the signature of a selective sweep in an ancestral population may still remain in its descendants. Identifying signatures of selection in the ancestor that are shared among its descendants is important to contextualize the timing of a sweep, but few methods exist for this purpose. We introduce the statistic SS-H12, which can identify genomic regions under shared positive selection across populations and is based on the theory of the expected haplotype homozygosity statistic H12, which detects recent hard and soft sweeps from the presence of high-frequency haplotypes. SS-H12 is distinct from comparable statistics because it requires a minimum of only two populations, and properly identifies and differentiates between independent convergent sweeps and true ancestral sweeps, with high power and robustness to a variety of demographic models. Furthermore, we can apply SS-H12 in conjunction with the ratio of statistics we term [Formula: see text] and [Formula: see text] to further classify identified shared sweeps as hard or soft. Finally, we identified both previously reported and novel shared sweep candidates from human whole-genome sequences. Previously reported candidates include the well-characterized ancestral sweeps at LCT and SLC24A5 in Indo-Europeans, as well as GPHN worldwide. Novel candidates include an ancestral sweep at RGS18 in sub-Saharan Africans involved in regulating the platelet response and implicated in sudden cardiac death, and a convergent sweep at C2CD5 between European and East Asian populations that may explain their different insulin responses.
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Affiliation(s)
- Alexandre M Harris
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802
- Molecular, Cellular, and Integrative Biosciences at the Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Michael DeGiorgio
- Department of Computer and Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, Florida 33431
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Grant WB, Fakhoury HMA, Karras SN, Al Anouti F, Bhattoa HP. Variations in 25-Hydroxyvitamin D in Countries from the Middle East and Europe: The Roles of UVB Exposure and Diet. Nutrients 2019; 11:E2065. [PMID: 31484329 PMCID: PMC6769941 DOI: 10.3390/nu11092065] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/09/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022] Open
Abstract
Serum 25-hydroxyvitamin D (25(OH)D) has been largely associated with latitude and sunshine exposure across several regions. According to previous results, 25(OH)D concentrations are, on average, relatively low in countries with abundant sunshine, including those of the Middle East and North Africa region, as well as lower-latitude Europe. The standard explanation for this phenomenon is that people wear concealing clothing because of cultural and religious practices and that high temperatures in summer limit direct sun exposure. However, the role of diet in the development of profound hypovitaminosis D has not been adequately explored in those countries. To examine how diet affects vitamin D status in the Middle Eastern and European countries, a search was conducted for papers from that region reporting 25(OH)D concentrations. Papers were sought that reported summertime and wintertime 25(OH)D concentrations for healthy nonpregnant adults representative of the entire population. Data from 15 Middle Eastern and European countries were found through this search. Data for postmenopausal women from 19 European countries were also obtained. Dietary supply data for animal products containing vitamin D (animal fat, eggs, ocean fish, animal meat, and milk) were obtained from the Food and Agriculture Organization of the United Nations. Latitude and a solar UVB dose index also were obtained for each country. For the 15-country study, energy from dietary factors was highly correlated with latitude, making it difficult to separate the effects of UVB exposure and dietary factors. However, for the 19-country study, dietary factors were only weakly correlated with latitude. In that study, ocean fish was the most important single dietary factor affecting serum 25(OH)D concentration for postmenopausal women in various European countries, but animal fat and meat also contributed. Because this is an ecological study, further research is encouraged to evaluate and extend the findings.
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Affiliation(s)
- William B Grant
- Director, Sunlight, Nutrition, and Health Research Center, P.O. Box 641603, San Francisco, CA 94164-1603, USA.
| | - Hana M A Fakhoury
- Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, P.O. Box 50927, Riyadh 11533, Saudi Arabia
| | - Spyridon N Karras
- Division of Endocrinology and Metabolism and Diabetes Center, First Department of Internal Medicine, Medical School, Aristotle University of Thessaloniki, AHEPA University Hospital, 55535 Thessaloniki, Greece
| | - Fatme Al Anouti
- College of Natural and Health Sciences, Department of Public Health and Nutrition, Zayed University, P.O. Box 4783, Abu Dhabi 144534, UAE
| | - Harjit P Bhattoa
- Endocrinology Unit and Andrology and Cryopreservation Unit, Department of Laboratory Medicine, Faculty of Medicine University of Debrecen Nagyerdei krt. 98, H-4032 Debrecen, Hungary
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Jablonski NG, Chaplin G. The roles of vitamin D and cutaneous vitamin D production in human evolution and health. INTERNATIONAL JOURNAL OF PALEOPATHOLOGY 2018; 23:54-59. [PMID: 29606375 DOI: 10.1016/j.ijpp.2018.01.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 01/24/2018] [Accepted: 01/25/2018] [Indexed: 06/08/2023]
Abstract
Most of the vitamin D necessary for the maintenance of human health and successful reproduction is made in the skin under the influence of a narrow portion of the electromagnetic spectrum emitted from the sun, namely ultraviolet B radiation (UVB). During the course of human evolution, skin pigmentation has evolved to afford protection against high levels of UVR while still permitting cutaneous production of vitamin D. Similar pigmentation phenotypes evolved repeatedly as the result of independent genetic events when isolated human populations dispersed into habitats of extremely low or high UVB. The gradient of skin color seen in modern human populations is evidence of the operation of two clines, one favoring photoprotection near the equator, the other favoring vitamin D production nearer the poles. Through time, human adaptations to different solar regimes have become more cultural than biological. Rapid human migrations, increasing urbanization, and changes in lifestyle have created mismatches between skin pigmentation and environmental conditions leading to vitamin D deficiency. The prevalence and significance for health of vitamin D deficiencies, and the definition of optimal levels of vitamin D in the bloodstream are subjects of intense research and debate, but two of the causes of vitamin D deficiency - lack of sun exposure and abandonment of vitamin D rich foods in the diet - are traceable to changes in human lifestyles accompanying urbanization in prehistory.
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Affiliation(s)
- Nina G Jablonski
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, United States.
| | - George Chaplin
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, United States
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Mays S, Prowse T, George M, Brickley M. Latitude, urbanization, age, and sex as risk factors for vitamin D deficiency disease in the Roman Empire. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 167:484-496. [DOI: 10.1002/ajpa.23646] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/08/2018] [Accepted: 06/14/2018] [Indexed: 12/16/2022]
Affiliation(s)
- S. Mays
- Research Department; Historic England; Portsmouth United Kingdom
- Department of Archaeology; University of Southampton; Southampton United Kingdom
- School of History, Classics and Archaeology; University of Edinburgh; Edinburgh United Kingdom
| | - T. Prowse
- Department of Anthropology; McMaster University; Hamilton Ontario Canada
| | - M. George
- Department of Classics; McMaster University; Hamilton Ontario Canada
| | - M. Brickley
- Department of Anthropology; McMaster University; Hamilton Ontario Canada
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Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. Proc Natl Acad Sci U S A 2018; 115:E4426-E4432. [PMID: 29686092 PMCID: PMC5948952 DOI: 10.1073/pnas.1711788115] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The frequency of the human-specific EDAR V370A isoform is highly elevated in North and East Asian populations. The gene is known to have several pleiotropic effects, among which are sweat gland density and ductal branching in the mammary gland. The former has led some geneticists to argue that the near-fixation of this allele was caused by selection for modulation of thermoregulatory sweating. We provide an alternative hypothesis, that selection instead acted on the allele’s effect of increasing ductal branching in the mammary gland, thereby amplifying the transfer of critical nutrients to infants via mother’s milk. This is likely to have occurred during the Last Glacial Maximum when a human population was genetically isolated in the high-latitude environment of the Beringia. Because of the ubiquitous adaptability of our material culture, some human populations have occupied extreme environments that intensified selection on existing genomic variation. By 32,000 years ago, people were living in Arctic Beringia, and during the Last Glacial Maximum (LGM; 28,000–18,000 y ago), they likely persisted in the Beringian refugium. Such high latitudes provide only very low levels of UV radiation, and can thereby lead to dangerously low levels of biosynthesized vitamin D. The physiological effects of vitamin D deficiency range from reduced dietary absorption of calcium to a compromised immune system and modified adipose tissue function. The ectodysplasin A receptor (EDAR) gene has a range of pleiotropic effects, including sweat gland density, incisor shoveling, and mammary gland ductal branching. The frequency of the human-specific EDAR V370A allele appears to be uniquely elevated in North and East Asian and New World populations due to a bout of positive selection likely to have occurred circa 20,000 y ago. The dental pleiotropic effects of this allele suggest an even higher occurrence among indigenous people in the Western Hemisphere before European colonization. We hypothesize that selection on EDAR V370A occurred in the Beringian refugium because it increases mammary ductal branching, and thereby may amplify the transfer of critical nutrients in vitamin D-deficient conditions to infants via mothers’ milk. This hypothesized selective context for EDAR V370A was likely intertwined with selection on the fatty acid desaturase (FADS) gene cluster because it is known to modulate lipid profiles transmitted to milk from a vitamin D-rich diet high in omega-3 fatty acids.
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Marciniak S, Perry GH. Harnessing ancient genomes to study the history of human adaptation. Nat Rev Genet 2017; 18:659-674. [PMID: 28890534 DOI: 10.1038/nrg.2017.65] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The past several years have witnessed an explosion of successful ancient human genome-sequencing projects, with genomic-scale ancient DNA data sets now available for more than 1,100 ancient human and archaic hominin (for example, Neandertal) individuals. Recent 'evolution in action' analyses have started using these data sets to identify and track the spatiotemporal trajectories of genetic variants associated with human adaptations to novel and changing environments, agricultural lifestyles, and introduced or co-evolving pathogens. Together with evidence of adaptive introgression of genetic variants from archaic hominins to humans and emerging ancient genome data sets for domesticated animals and plants, these studies provide novel insights into human evolution and the evolutionary consequences of human behaviour that go well beyond those that can be obtained from modern genomic data or the fossil and archaeological records alone.
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Affiliation(s)
- Stephanie Marciniak
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - George H Perry
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Manios Y, Moschonis G, Lambrinou CP, Tsoutsoulopoulou K, Binou P, Karachaliou A, Breidenassel C, Gonzalez-Gross M, Kiely M, Cashman KD. A systematic review of vitamin D status in southern European countries. Eur J Nutr 2017; 57:2001-2036. [PMID: 29090332 DOI: 10.1007/s00394-017-1564-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 10/07/2017] [Indexed: 12/16/2022]
Abstract
PURPOSE Despite an acknowledged dearth of data on serum 25-hydroxyvitamin D (25(OH)D) concentrations from Southern European countries, inter-country comparison is hampered by inconsistent data reporting. The purpose of the current study was to conduct a systematic literature review of available data on serum 25(OH)D concentrations and estimate vitamin D status in Southern European and Eastern Mediterranean countries, both at a population level and within key population subgroups, stratified by age, sex, season and country. METHODS A systematic review of the literature was conducted to identify and retrieve scientific articles reporting data on serum 25(OH)D concentration and/or vitamin D status following standard procedures. RESULTS Data were extracted from 107 studies, stratified by sex and age group, representing 630,093 individuals. More than one-third of the studies reported mean 25(OH)D concentrations below 50 nmol/L and ~ 10% reported mean serum 25(OH)D concentrations below 25 nmol/L. Overall, females, neonates/ infants and adolescents had the higher prevalence of poor vitamin D status. As expected, there was considerable variability between studies. Specifically, mean 25(OH)D ranged from 6.0 (in Italian centenarians) to 158 nmol/L (in elderly Turkish men); the prevalence of serum 25(OH)D < 50 nmol/L ranged from 6.8 to 97.9% (in Italian neonates). CONCLUSIONS Contrary to expectations, there was a high prevalence of low vitamin D status in the Southern Europe and the Eastern Mediterranean regions, despite abundant sunshine. These data further emphasize the need for strategies, such as fortification of foods with vitamin D and/or vitamin D supplementation, which will be tailored to the needs of specific population groups with higher risk of insufficiency or deficiency, to efficiently tackle the pandemic of hypovitaminosis D in Europe.
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Affiliation(s)
- Yannis Manios
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, 70 El Venizelou Avenue, Kallithea, 17671, Athens, Greece.
| | - George Moschonis
- Department of Rehabilitation, Nutrition and Sport, College of Science, Health and Engineering, La Trobe University, Bundoora, 3086, Melbourne, Australia
| | - Christina-Paulina Lambrinou
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, 70 El Venizelou Avenue, Kallithea, 17671, Athens, Greece
| | - Konstantina Tsoutsoulopoulou
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, 70 El Venizelou Avenue, Kallithea, 17671, Athens, Greece
| | - Panagiota Binou
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, 70 El Venizelou Avenue, Kallithea, 17671, Athens, Greece
| | - Alexandra Karachaliou
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, 70 El Venizelou Avenue, Kallithea, 17671, Athens, Greece
| | - Christina Breidenassel
- ImFINE Research Group, Department of Health and Human Performance, Universidad Politécnica de Madrid, Madrid, Spain
| | - Marcela Gonzalez-Gross
- ImFINE Research Group, Department of Health and Human Performance, Universidad Politécnica de Madrid, Madrid, Spain
| | - Mairead Kiely
- Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.,The Irish Centre for Fetal and Neonatal Translational Research (INFANT), University College Cork, Cork, Ireland
| | - Kevin D Cashman
- Cork Centre for Vitamin D and Nutrition Research, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.,Department of Medicine, University College Cork, Cork, Ireland
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Bromage S, Tselmen D, Bradwin G, Holick MF, Ganmaa D. Validation of summer and winter ELISA measurements of serum 25-hydroxyvitamin D concentrations in Mongolia. Asia Pac J Clin Nutr 2017; 26:987-993. [PMID: 28917222 DOI: 10.6133/apjcn.122016.02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND AND OBJECTIVES Assay cost, quality, and availability pose challenges for vitamin D surveys in limited resource settings. This study aimed to validate an inexpensive vitamin D assay (ELISA) under real-world conditions in Mongolia, the northernmost developing country, to characterize the assay's usefulness and inform the design of epidemiologic studies in similar regions. METHODS AND STUDY DESIGN We collected paired summer and winter serum samples from 120 men and women (aged 20-57 years) in urban and rural Mongolia, analyzed each sample for 25(OH)D concentration using both Immunodiagnostic Systems ELISA and DiaSorin LIAISON 25(OH)D TOTAL, and compared the assays using multiple statistics. LIAISON was itself validated by participation in the DEQAS program. RESULTS Correlation and agreement between assays were higher in summer (Pearson's correlation=0.60, Spearman's rank correlation=0.67, Lin's concordance correlation=0.56) than winter (rP=0.37, rS=0.43, rC=0.33), although ELISA less accurately assigned subjects to sufficiency categories in summer (percent agreement=44%) than winter (58%), during the latter of which most subjects were deficient ([25(OH)D] categories used: >75 nmol/L (optimal), 50-75 nmol/L (adequate), 25-50 nmol/L (inadequate), <25 nmol/L (deficient)). Compared with LIAISON, ELISA tended to indicate higher vitamin D status in both seasons (mean paired difference: 7.0 nmol/L (95% CI: 3.5-10.5) in summer, 5.2 nmol/L (95% CI: 2.9-7.5) in winter). CONCLUSIONS ELISA proved useful for measuring and ranking subjects' vitamin D status in Mongolia during summer, but levels were too low in winter to sensitively discriminate between subjects, and ELISA overestimated status in both seasons. These findings have implications for the timing and interpretation, respectively, of vitamin D surveys in highly deficient populations.
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Affiliation(s)
- Sabri Bromage
- Harvard T.H. Chan School of Public Health, United States.
| | | | - Gary Bradwin
- Boston Children's Hospital, United States.,Harvard Medical School, United States
| | | | - Davaasaambuu Ganmaa
- Harvard T.H. Chan School of Public Health, United States.,Harvard Medical School, United States.,Brigham and Women's Hospital, United States
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16
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Rühli F, van Schaik K, Henneberg M. Evolutionary Medicine: The Ongoing Evolution of Human Physiology and Metabolism. Physiology (Bethesda) 2017; 31:392-397. [PMID: 27708045 DOI: 10.1152/physiol.00013.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The field of evolutionary medicine uses evolutionary principles to understand changes in human anatomy and physiology that have occurred over time in response to environmental changes. Through this evolutionary-based approach, we can understand disease as a consequence of anatomical and physiological "trade-offs" that develop to facilitate survival and reproduction. We demonstrate how diachronic study of human anatomy and physiology is fundamental for an increased understanding of human health and disease.
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Affiliation(s)
- Frank Rühli
- Institute of Evolutionary Medicine, University of Zurich, Zurich, Switzerland;
| | - Katherine van Schaik
- Institute of Evolutionary Medicine, University of Zurich, Zurich, Switzerland; Harvard Medical School and Harvard Department of the Classics, Harvard University, Cambridge, Massachusetts; and
| | - Maciej Henneberg
- Institute of Evolutionary Medicine, University of Zurich, Zurich, Switzerland; Adelaide Medical School, The University of Adelaide, Adelaide, Australia
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17
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Jablonski NG, Chaplin G. The colours of humanity: the evolution of pigmentation in the human lineage. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160349. [PMID: 28533464 PMCID: PMC5444068 DOI: 10.1098/rstb.2016.0349] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2016] [Indexed: 12/16/2022] Open
Abstract
Humans are a colourful species of primate, with human skin, hair and eye coloration having been influenced by a great variety of evolutionary forces throughout prehistory. Functionally naked skin has been the physical interface between the physical environment and the human body for most of the history of the genus Homo, and hence skin coloration has been under intense natural selection. From an original condition of protective, dark, eumelanin-enriched coloration in early tropical-dwelling Homo and Homo sapiens, loss of melanin pigmentation occurred under natural selection as Homo sapiens dispersed into non-tropical latitudes of Africa and Eurasia. Genes responsible for skin, hair and eye coloration appear to have been affected significantly by population bottlenecks in the course of Homo sapiens dispersals. Because specific skin colour phenotypes can be created by different combinations of skin colour-associated genetic markers, loss of genetic variability due to genetic drift appears to have had negligible effects on the highly redundant genetic 'palette' for the skin colour. This does not appear to have been the case for hair and eye coloration, however, and these traits appear to have been more strongly influenced by genetic drift and, possibly, sexual selection.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.
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Affiliation(s)
- Nina G Jablonski
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
| | - George Chaplin
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
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18
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O’Brien DM, Thummel KE, Bulkow LR, Wang Z, Corbin B, Klejka J, Hopkins SE, Boyer BB, Hennessy TW, Singleton R. Declines in traditional marine food intake and vitamin D levels from the 1960s to present in young Alaska Native women. Public Health Nutr 2017; 20:1738-1745. [PMID: 27465921 PMCID: PMC5274583 DOI: 10.1017/s1368980016001853] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/23/2016] [Accepted: 06/15/2016] [Indexed: 01/19/2023]
Abstract
OBJECTIVE To measure the trends in traditional marine food intake and serum vitamin D levels in Alaska Native women of childbearing age (20-29 years old) from the 1960s to the present. DESIGN We measured a biomarker of traditional food intake, the δ15N value, and vitamin D level, as 25-hydroxycholecalciferol (25(OH)D3) concentration, in 100 serum samples from 20-29-year-old women archived in the Alaska Area Specimen Bank, selecting twenty-five per decade from the 1960s to the 1990s. We compared these with measurements of red-blood-cell δ15N values and serum 25(OH)D3 concentrations from 20-29-year-old women from the same region collected during the 2000s and 2010s in a Center for Alaska Native Health Research study. SETTING The Yukon Kuskokwim Delta region of south-west Alaska. SUBJECTS Alaska Native women (n 319) aged 20-29 years at the time of specimen collection. RESULTS Intake of traditional marine foods, as measured by serum δ15N values, decreased significantly each decade from the 1960s through the 1990s, then remained constant from the 1990s through the present (F 5,306=77·4, P<0·0001). Serum vitamin D concentrations also decreased from the 1960s to the present (F 4,162=26·1, P<0·0001). CONCLUSIONS Consumption of traditional marine foods by young Alaska Native women dropped significantly between the 1960s and the 1990s and was associated with a significant decline in serum vitamin D concentrations. Studies are needed to evaluate the promotion of traditional marine foods and routine vitamin D supplementation during pregnancy for this population.
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Affiliation(s)
- Diane M O’Brien
- Center for Alaska Native Health Research, Institute of Arctic Biology, University of Alaska, PO Box 757000, Fairbanks, AK 99775–7000, USA
- Department of Biology and Wildlife, University of Alaska, Fairbanks, AK, USA
| | | | - Lisa R Bulkow
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA
| | - Zhican Wang
- School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Brittany Corbin
- Department of Biology and Wildlife, University of Alaska, Fairbanks, AK, USA
| | | | - Scarlett E Hopkins
- Center for Alaska Native Health Research, Institute of Arctic Biology, University of Alaska, PO Box 757000, Fairbanks, AK 99775–7000, USA
| | - Bert B Boyer
- Center for Alaska Native Health Research, Institute of Arctic Biology, University of Alaska, PO Box 757000, Fairbanks, AK 99775–7000, USA
| | - Thomas W Hennessy
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA
| | - Rosalyn Singleton
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA
- Alaska Native Tribal Health Consortium, Division of Community Health Services, Anchorage, AK, USA
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Beckett EL, Jones P, Veysey M, Duesing K, Martin C, Furst J, Yates Z, Jablonski NG, Chaplin G, Lucock M. VDR gene methylation as a molecular adaption to light exposure: Historic, recent and genetic influences. Am J Hum Biol 2017; 29. [DOI: 10.1002/ajhb.23010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/24/2017] [Accepted: 04/01/2017] [Indexed: 01/14/2023] Open
Affiliation(s)
- Emma L Beckett
- School of Environmental & Life SciencesUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
- Medicine and Public HealthUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
- Food and Nutrition FlagshipCSIRO NSW Australia
| | - Patrice Jones
- School of Environmental & Life SciencesUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
| | - Martin Veysey
- Medicine and Public HealthUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
- Teaching & Research Unit, Central Coast Local Health DistrictPO Box 361, Gosford NSW2250 Australia
| | | | - Charlotte Martin
- School of Environmental & Life SciencesUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
| | - John Furst
- Maths & Physical SciencesUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
| | - Zoe Yates
- Biomedical Sciences & PharmacyUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
| | - Nina G. Jablonski
- Anthropology DepartmentThe Pennsylvania State University409 Carpenter Building, University Park Pennsylvania16802
| | - George Chaplin
- Anthropology DepartmentThe Pennsylvania State University409 Carpenter Building, University Park Pennsylvania16802
| | - Mark Lucock
- School of Environmental & Life SciencesUniversity of NewcastlePO Box 127, Brush Rd, Ourimbah NSW2258 Australia
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Göring H, Koshuchowa S. Vitamin D deficiency in Europeans today and in Viking settlers of Greenland. BIOCHEMISTRY (MOSCOW) 2016; 81:1492-1497. [DOI: 10.1134/s0006297916120117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
The well-documented latitudinal clines of genes affecting human skin color presumably arise from the need for protection from intense ultraviolet radiation (UVR) vs. the need to use UVR for vitamin D synthesis. Sampling 751 subjects from a broad range of latitudes and skin colors, we investigated possible multilocus correlated adaptation of skin color genes with the vitamin D receptor gene (VDR), using a vector correlation metric and network method called BlocBuster. We discovered two multilocus networks involving VDR promoter and skin color genes that display strong latitudinal clines as multilocus networks, even though many of their single gene components do not. Considered one by one, the VDR components of these networks show diverse patterns: no cline, a weak declining latitudinal cline outside of Africa, and a strong in- vs. out-of-Africa frequency pattern. We confirmed these results with independent data from HapMap. Standard linkage disequilibrium analyses did not detect these networks. We applied BlocBuster across the entire genome, showing that our networks are significant outliers for interchromosomal disequilibrium that overlap with environmental variation relevant to the genes’ functions. These results suggest that these multilocus correlations most likely arose from a combination of parallel selective responses to a common environmental variable and coadaptation, given the known Mendelian epistasis among VDR and the skin color genes.
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Boucher BJ. Re: Prime mover or fellow traveller: 25-hydroxyvitamin D's seasonal variation, cardiovascular disease and death in the Scottish Heart Health Extended Study. Int J Epidemiol 2016; 45:287-9. [PMID: 26792762 DOI: 10.1093/ije/dyv314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Barbara J Boucher
- The Blizard Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, UK.
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23
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Mirzakhani H, Al-Garawi A, Weiss ST, Litonjua AA. Vitamin D and the development of allergic disease: how important is it? Clin Exp Allergy 2015; 45:114-25. [PMID: 25307157 DOI: 10.1111/cea.12430] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Vitamin D has known effects on lung development and the immune system that may be important in the development, severity, and course of allergic diseases (asthma, eczema, and food allergy). Vitamin D deficiency is prevalent worldwide and may partly explain the increases in asthma and allergic diseases that have occurred over the last 50-60 years. In this review, we explore past and current knowledge on the effect of vitamin D on lung development and immunomodulation and present the evidence of its role in allergic conditions. While there is growing observational and experimental evidence for the role of vitamin D, well-designed and well-powered clinical trials are needed to determine whether supplementation of vitamin D should be recommended in these disorders.
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Affiliation(s)
- H Mirzakhani
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
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Daulatzai MA. “Boomerang Neuropathology” of Late-Onset Alzheimer’s Disease is Shrouded in Harmful “BDDS”: Breathing, Diet, Drinking, and Sleep During Aging. Neurotox Res 2015; 28:55-93. [DOI: 10.1007/s12640-015-9528-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 04/03/2015] [Accepted: 04/03/2015] [Indexed: 12/12/2022]
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Abstract
In recent years, new functional roles of vitamin D beyond its traditional role in calcium homoeostasis and bone metabolism have emerged linking the fat-soluble vitamin to various non-communicable diseases. Vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25-30 nmol/l) and sub-optimal status (25(OH)D < 50-100 nmol/l) are increasingly associated with unfavourable metabolic phenotypes, including insulin resistance, type 2 diabetes and CVD; conditions also commonly linked with overweight and obesity. Early studies reported poor vitamin D status in the morbidly obese. More recently, it has been observed that a graded relationship between vitamin D status and BMI, or specifically adiposity, exists in the general population. A number of hypotheses have been proposed to explain the potential mechanisms whereby alterations in the vitamin D endocrine system occur in the obese state. Plausible explanations include sequestration in adipose tissue, volumetric dilution or negative feedback mechanisms from increased circulating 1,25-dihydroxyvitamin D3. Others hypothesise that heavier individuals may partake in less outdoor activity, may also cover-up and wear more clothing than leaner individuals, thus decreasing sun exposure and limiting endogenous production of cholecalciferol in the skin. Moreover, in some but not all studies, BMI and adiposity have been negatively associated with the change in vitamin D status following vitamin D supplementation. It therefore remains unclear if body size and/or adiposity should be taken into account when determining the dietary requirements for vitamin D. This review will evaluate the current evidence linking vitamin D status and supplementation to overweight and obesity, and discuss the implications for setting dietary requirements.
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26
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Jablonski NG. Is there a golden mean for sun exposure? J Intern Med 2014; 276:71-3. [PMID: 24697849 DOI: 10.1111/joim.12248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- N G Jablonski
- Department of Anthropology, The Pennsylvania State University, University Park, PA, USA
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