Bio

Bio


Maryam Hamidi, PhD is a researcher at the Stanford Medicine WellMD Center and Department of Psychiatry and Behavioral Sciences. In her role, she is involved in development, implementation and evaluation of various innovative interventions to improve physicians’ well-being. Dr. Hamidi has particular nutrition expertise in enhancing the cognitive performance and alertness of professionals with high cognitive demands. The focus of her current work is to use latest scientific evidence to improve the cognitive performance and overall well-being of physicians at Stanford Medicine.

Dr. Hamidi completed her graduate studies in nutritional sciences at University of Toronto in Canada and is the author and co-author of many highly cited scientific papers on nutrition and well-being. Prior to coming to Stanford she served as a scientific associate at the University Health Network of Toronto, and as an advisor to Air Canada Rouge pilots and cabin crew on optimal nutrition.

Current Role at Stanford


Associate Director of Scholarship & Health Promotion at Stanford Medicine WellMD Center
Research Professional at Department of Psychiatry and Behavioral Sciences

Education & Certifications


  • PhD, University of Toronto, Institute of Medical Science, Nutritional Epidemiology (2012)
  • MSc, University of Toronto, Department of Nutritional Sciences, Clinical Nutrition (2002)

Publications

All Publications


  • Physician Well-Being: The Reciprocity of Practice Efficiency, Culture of Wellness, and Personal Resilience Bohman, B. NEJM Catalyst. 2017 ; Leadership

    Abstract

    Think of physician well-being as a three-legged stool. Improvement efforts should focus on all three domains to achieve best results.

  • A Brief Instrument to Assess Both Burnout and Professional Fulfillment in Physicians: Reliability and Validity, Including Correlation with Self-Reported Medical Errors, in a Sample of Resident and Practicing Physicians. Academic psychiatry : the journal of the American Association of Directors of Psychiatric Residency Training and the Association for Academic Psychiatry Trockel, M., Bohman, B., Lesure, E., Hamidi, M. S., Welle, D., Roberts, L., Shanafelt, T. 2017

    Abstract

    The objective of this study was to evaluate the performance of the Professional Fulfillment Index (PFI), a 16-item instrument to assess physicians' professional fulfillment and burnout, designed for sensitivity to change attributable to interventions or other factors affecting physician well-being.A sample of 250 physicians completed the PFI, a measure of self-reported medical errors, and previously validated measures including the Maslach Burnout Inventory (MBI), a one-item burnout measure, the World Health Organization's abbreviated quality of life assessment (WHOQOL-BREF), and PROMIS short-form depression, anxiety, and sleep-related impairment scales. Between 2 and 3 weeks later, 227 (91%) repeated the PFI and the sleep-related impairment scale.Principal components analysis justified PFI subscales for professional fulfillment, work exhaustion, and interpersonal disengagement. Test-retest reliability estimates were 0.82 for professional fulfillment (α = 0.91), 0.80 for work exhaustion (α = 0.86), 0.71 for interpersonal disengagement (α = 0.92), and 0.80 for overall burnout (α = 0.92). PFI burnout measures correlated highly (r ≥ 0.50) with their closest related MBI equivalents. Cohen's d effect size differences in self-reported medical errors for high versus low burnout classified using the PFI and the MBI were 0.55 and 0.44, respectively. PFI scales correlated in expected directions with sleep-related impairment, depression, anxiety, and WHOQOL-BREF scores. PFI scales demonstrated sufficient sensitivity to detect expected effects of a two-point (range 8-40) change in sleep-related impairment.PFI scales have good performance characteristics including sensitivity to change and offer a novel contribution by assessing professional fulfillment in addition to burnout.

    View details for DOI 10.1007/s40596-017-0849-3

    View details for PubMedID 29196982

  • Improving bone health in men with prostate cancer receiving androgen deprivation therapy: Results of a randomized phase 2 trial. Cancer Alibhai, S. M., Breunis, H., Timilshina, N., Hamidi, M. S., Cheung, A. M., Tomlinson, G. A., Manokumar, T., Samadi, O., Sandoval, J., Durbano, S., Warde, P., Jones, J. M. 2017

    Abstract

    Strategies to improve bone health care in men receiving androgen deprivation therapy (ADT) are not consistently implemented. The authors conducted a phase 2 randomized controlled trial of 2 education-based models-of-care interventions to determine their feasibility and ability to improve bone health care.A single-center parallel-group randomized controlled trial of men with prostate cancer who were receiving ADT was performed. Participants were randomized 1:1:1 to 1) a patient bone health pamphlet and brief recommendations for their family physician (BHP+FP); 2) a BHP and support from a bone health care coordinator (BHP+BHCC); or 3) usual care. The primary efficacy outcome was receipt of a bone mineral density (BMD) test within 6 months. Secondary efficacy outcomes included guideline-appropriate calcium and vitamin D use and bisphosphonate prescriptions for men at high fracture risk. Feasibility endpoints included recruitment, retention, satisfaction, contamination, and outcome capture. The main analysis used logistic regression with a 1-sided P of .10. The trial is registered at ClinicalTrials.gov (identifier NCT02043236).A total of 119 men were recruited. The BHP+BHCC strategy was associated with a greater percentage of men undergoing a BMD test compared with the usual-care group (78% vs 36%; P<.001). BMD ordering also was found to be increased with the BHP+FP strategy (58% vs 36%; P = .047). Both strategies were associated with higher percentages of patients using calcium and vitamin D, but only the BHP+FP arm was statistically significant (P = .039). No men were detected to be at high fracture risk. All but one feasibility endpoint was met.Educational strategies to improve bone health care appear feasible and are associated with improved BMD ordering in men receiving ADT. Cancer 2017. © 2017 American Cancer Society.

    View details for DOI 10.1002/cncr.31171

    View details for PubMedID 29211305

  • Running on empty: a review of nutrition and physicians' well-being POSTGRADUATE MEDICAL JOURNAL Hamidi, M. S., Boggild, M. K., Cheung, A. M. 2016; 92 (1090): 478-481

    Abstract

    Resident and physician burnout is a complex issue. Adequate nutrition and hydration play important roles in the maintenance of health and well-being of all individuals. Given the high prevalence of burnout in physicians, we believe that in addition to issues related to heavy workload, structure and length of shifts, the current status of physicians' nutrition and hydration and their effects on their work performance and well-being should also be addressed. In this review, we summarise the current evidence on the potential effects of nutrition and hydration on physicians' occupational well-being and performance, identify gaps and discuss opportunities to address nutrition as one of the important means of improving physicians' well-being.

    View details for DOI 10.1136/postgradmedj-2016-134131

    View details for Web of Science ID 000380942700011

    View details for PubMedID 27215232

  • Vitamin K and musculoskeletal health in postmenopausal women MOLECULAR NUTRITION & FOOD RESEARCH Hamidi, M. S., Cheung, A. M. 2014; 58 (8): 1647-1657

    Abstract

    Aside from its important role in blood clotting, vitamin K is an important dietary factor in regulating bone and cartilage mineralization. The vitamin K requirements to maintain musculoskeletal health may be more than the current recommendations and subclinical vitamin K deficiency may be involved in the pathogenesis of osteoporosis and osteoarthritis. Observational studies suggest that diets low in vitamin K are associated with increased risk of fractures and osteoarthritis in older adults. However, so far randomized controlled trials of vitamin K supplementation in Caucasian populations have not shown clinically significant improvements in bone mineral density at major skeletal sites. Supplementation with vitamin K may reduce the risk of fractures, but this conclusion comes from clinical trials with methodological limitations. At this time, only one randomized controlled trial has examined the effect of vitamin K supplementation on radiographic hand osteoarthritis and found no overall effect. Large well-designed randomized controlled trials are needed to compare the efficacies of vitamin K1 and K2 on fractures and osteoarthritis among older adults. In summary, currently there is not enough evidence to recommend the use of vitamin K supplements for the prevention of bone loss, fractures, or osteoarthritis in postmenopausal women.

    View details for DOI 10.1002/mnfr.201300950

    View details for Web of Science ID 000340528500007

    View details for PubMedID 24956598

  • Vitamin K and Bone Health JOURNAL OF CLINICAL DENSITOMETRY Hamidi, M. S., Gajic-Veljanoski, O., Cheung, A. M. 2013; 16 (4): 409-413

    Abstract

    Vitamin K has been purported to play an important role in bone health. It is required for the gamma-carboxylation of osteocalcin (the most abundant noncollagenous protein in bone), making osteocalcin functional. There are 2 main forms (vitamin K1 and vitamin K2), and they come from different sources and have different biological activities. Epidemiologic studies suggest a diet high in vitamin K is associated with a lower risk of hip fractures in aging men and women. However, randomized controlled trials of vitamin K1 or K2 supplementation in white populations did not increase bone mineral density at major skeletal sites. Supplementation with vitamin K1 and K2 may reduce the risk of fractures, but the trials that examined fractures as an outcome have methodological limitations. Large well-designed trials are needed to compare the efficacies of vitamin K1 and K2 on fractures. We conclude that currently there is not enough evidence to recommend the routine use of vitamin K supplements for the prevention of osteoporosis and fractures in postmenopausal women.

    View details for DOI 10.1016/j.jocd.2013.08.017

    View details for Web of Science ID 000326851500006

    View details for PubMedID 24090644

  • Effects of vitamin E on bone turnover markers among US postmenopausal women JOURNAL OF BONE AND MINERAL RESEARCH Hamidi, M. S., Corey, P. N., Cheung, A. M. 2012; 27 (6): 1368-1380

    Abstract

    Increased oxidative stress and inflammation resulting from aging and declining estrogen levels can lead to increased bone loss in postmenopausal women. Alpha-tocopherol and gamma-tocopherol, the two predominant isomers of vitamin E, have antioxidant and anti-inflammatory properties, but their effects on bone metabolism have not been well studied in humans. We examined the associations between dietary and total (diet and supplements) alpha-tocopherol intake, serum alpha-tocopherol and gamma-tocopherol levels and their ratio, and bone turnover markers (BTMs) among postmenopausal women aged ≥45 years. We used cross-sectional data from the National Health and Nutrition Examination Survey 1999–2002. Multiple regression models with adjustments for relevant confounders were used to examine the associations between intake and serum levels of tocopherols, and serum bone-specific alkaline phosphatase (BAP), a biomarker of bone formation, and urinary N-telopeptides/creatinine (uNTx/Cr), a biomarker of bone resorption. The study sample included 497 postmenopausal women who were not taking estrogen, steroids, or osteoporosis medications, were free from kidney and liver disease, cancer, and rheumatoid arthritis, and were fasting >9 hours prior to examination. Participants had a mean age of 65.5 ± 0.6 years and over 45% used vitamin E (alpha-tocopherol) supplements in the past month. Vitamin E supplement users had significantly lower serum gamma-tocopherol, higher serum alpha-tocopherol levels, and higher ratio of serum alpha-tocopherol to gamma-tocopherol than nonusers. High serum gamma-tocopherol levels and low ratio of serum alpha-tocopherol to gamma-tocopherol were associated with increased BAP levels (p < 0.01 for both). There were no associations between any of the vitamin E variables and uNTx/Cr. In conclusion, we hypothesize that gamma-tocopherol may uncouple bone turnover, resulting in more bone formation than resorption. Vitamin E supplements in the form of alpha-tocopherol suppress serum gamma-tocopherol levels and may have negative effects on bone formation. Further research is needed to investigate the potential anabolic effect of gamma-tocopherol from food sources on bone.

    View details for DOI 10.1002/jbmr.1566

    View details for Web of Science ID 000304141500014

    View details for PubMedID 22308007

  • Association between the Healthy Eating Index and bone turnover markers in US postmenopausal women aged >= 45 y AMERICAN JOURNAL OF CLINICAL NUTRITION Hamidi, M., Tarasuk, V., Corey, P., Cheung, A. M. 2011; 94 (1): 199-208

    Abstract

    Some studies have reported that overall diet quality affects bone status in postmenopausal women; however, the findings are inconsistent.Our primary objective was to examine the association between overall diet quality and bone turnover markers (BTMs) in postmenopausal women aged ≥45 y by using the Healthy Eating Index 2005 (HEI-2005)-a diet quality-assessment tool-developed by the US Department of Agriculture. Our secondary objective was to explore the associations between the components of the HEI-2005 and the MyPyramid food groups and BTMs.We used cross-sectional data from NHANES 1999-2002. Multiple regression models with adjustments for relevant confounders were used to examine the relation between the total HEI-2005 score and its components and food groups and serum bone-specific alkaline phosphatase (BAP), a biomarker of bone formation, and urinary N-telopeptides/creatinine (uNTx/Cr), a biomarker of bone resorption.No association was found between the total HEI-2005 score and BTMs. The milk group component of HEI-2005 had a significant negative linear relation with uNTx/Cr. Women in the lowest tertile of the MyPyramid milk group had the highest uNTx/Cr. Those in the highest tertile of energy-adjusted added sugar intake had the highest BAP.Our results support the ability of a healthy diet with adequate dairy intake to promote bone health in aging women. However, we found that the HEI-2005 is not a good measure of healthy eating for optimal bone health. Further research is needed to develop an overall dietary assessment tool in relation to bone health for postmenopausal women.

    View details for DOI 10.3945/ajcn.110.009605

    View details for Web of Science ID 000291794800028

    View details for PubMedID 21562084

  • Fruit and vegetable intake and bone health in women aged 45 years and over: a systematic review OSTEOPOROSIS INTERNATIONAL Hamidi, M., Boucher, B. A., Cheung, A. M., Beyene, J., Shah, P. S. 2011; 22 (6): 1681-1693

    Abstract

    High fruit and vegetable intake may be associated with improved bone status among women aged ≥ 45 years. This is the first systematic review that specifically assessed this association and identified research gaps. The benefits of fruit and vegetables (F&V) on bone health remain unclear. Further studies are needed.F&V have several components that are beneficial to bones. Some studies report that high F&V intake is associated with improved bone status in middle aged and aged women; however, findings are inconsistent. The objective was to systematically review observational and interventional studies that investigated the effects of F&V intake on incidence of osteoporotic fractures, bone mineral density (BMD), and bone turnover markers (BTM) in women aged ≥ 45 years and to identify potential research gaps.Electronic databases were searched, and peer-reviewed manuscripts published in English, with F&V intake as a main dietary exposure, were included. Data selection, extraction, and evaluation of risk of bias were performed independently by two reviewers.Eight studies were included. One cohort study reported cross-sectional as well as longitudinal data. There was significant between-study heterogeneity in design, definition, and amount of F&V intake, outcomes, analyses, and reporting of results. Two studies had low, two had moderate, and four had high risk of bias. Among reports with low or moderate risk of bias, two cross-sectional analyses reported positive associations between F&V intake and BMD of the forearm, lumbar spine, or total hip, whereas one randomized controlled trial and two prospective cohort analyses reported no effects. One trial reported no associations between F&V and BTM.Based on limited evidence, the benefits of F&V on bone health remain unclear for women aged ≥ 45 years. Further studies with low risk of bias are needed.

    View details for DOI 10.1007/s00198-010-1510-0

    View details for Web of Science ID 000290544900005

    View details for PubMedID 21165601

  • Validation of a calcium assessment tool in postmenopausal Canadian women MATURITAS Hung, A., Hamidi, M., Riazantseva, E., Thompson, L., Tile, L., Tomlinson, G., Stewart, B., Cheung, A. M. 2011; 69 (2): 168-172

    Abstract

    Adequate calcium intake is important for optimal bone health. Assessing dietary calcium intake, however, is neither widely done nor standardized in North American clinical practices.Our goal was to validate a calcium assessment tool (CAT), a modified version of the Calcium Calculator™, against the 3-day food record.Data were obtained from 348 participants in the ECKO (Evaluation of the Clinical use of vitamin K supplementation in postmenopausal women with Osteopenia) trial. In this study, CAT data was collected at baseline and 3-day food records (FRs) were collected at baseline and 3 months by trained study coordinators. CAT and 3-day FR data were compared using correlations and Bland-Altman plots. Additionally, receiver operator characteristic (ROC) curves of CAT were constructed to identify subjects with low calcium intake at thresholds of 500 mg/day and 1000 mg/day on the 3-day FR curves.Mean calcium intake values per day were 902 mg for the 3-day FRs and 781 mg for the CAT. The Pearson correlation was 0.57 (95% CI: 0.50-0.64). Areas under the ROC curves at thresholds of 500 and 1000 mg calcium were 0.81 (95% CI: 0.73-0.89) and 0.82 (95% CI: 0.78-0.86), respectively.The CAT is a valid tool for the measurement of dietary calcium intake using cut-off values of 500 mg and 1000 mg in postmenopausal women, even though there is only moderate correlation between the CAT and 3-day FR. This tool may facilitate the determination of whether calcium supplements are needed in the clinical setting.

    View details for DOI 10.1016/j.maturitas.2011.02.016

    View details for Web of Science ID 000291837600013

    View details for PubMedID 21450422

  • Effect of antibiotics as cholesterol-lowering agents METABOLISM-CLINICAL AND EXPERIMENTAL Jenkins, D. J., Kendall, C. W., HAMIDI, M., Vidgen, E., Faulkner, D., Parker, T., Irani, N., Wolever, T. M., Fong, I., Kopplin, P., Connelly, P. W., Onderdonk, A., Rao, A. V. 2005; 54 (1): 103-112

    Abstract

    Antibiotics were once proposed as hypercholesterolemic agents although the mechanism is unclear, despite broad implications, including providing an alternative approach to cholesterol reduction, with potential relevance for current trials of antibiotics to reduce cardiovascular disease, and possible confounding of routine diagnostic cholesterol measurements. The effect on serum lipids of antibiotics against aerobes and anaerobes, together with possible mechanisms, was therefore explored. Twenty-two men and women took antibiotics for 10 days (either ciprofloxacin for 13 subjects or metronidazole for 10 subjects), with 10 days control in random order separated by 2-week washout periods. Subjects maintained low-fat diets throughout the study. Blood samples and blood pressure were obtained on days 0 and 10 of each phase with 3-day fecal collections and 12-hour breath gas collections at the end of each phase. The results indicated that metronidazole markedly reduced low-density lipoprotein cholesterol (-14.0 +/- 4.0%, P = .006), oxidized low-density lipoprotein (-23.0 +/- 5.1%, P = .002), and the apolipoprotein B/A-I ratio (-18.0 +/- 2.8%, P < .001), whereas the reduction with ciprofloxacin was less pronounced (apolipoprotein B/A-I, -5.0 +/- 1.8%, P = .017). Neither antibiotic altered C-reactive protein or blood pressure. The low-density lipoprotein cholesterol reduction related to an increase in bifidobacteria (r = -0.46, P = .029), but not to markers of colonic fermentation. We conclude that antibiotics can reduce serum lipids acutely. These effects may confound diagnostic measurements but indicate possible links between colonic microflora and blood lipids and the need to study ways of altering colonic microflora by nonantibiotic means as a potential therapeutic option.

    View details for DOI 10.1016/j.metabol.2004.07.019

    View details for Web of Science ID 000228794600015

    View details for PubMedID 15562388

  • Glycemic index: overview of implications in health and disease AMERICAN JOURNAL OF CLINICAL NUTRITION Jenkins, D. J., Kendall, C. W., Augustin, L. S., Franceschi, S., HAMIDI, M., Marchie, A., Jenkins, A. L., Axelsen, M. 2002; 76 (1): 266S-273S

    Abstract

    The glycemic index concept is an extension of the fiber hypothesis, suggesting that fiber consumption reduces the rate of nutrient influx from the gut. The glycemic index has particular relevance to those chronic Western diseases associated with central obesity and insulin resistance. Early studies showed that starchy carbohydrate foods have very different effects on postprandial blood glucose and insulin responses in healthy and diabetic subjects, depending on the rate of digestion. A range of factors associated with food consumption was later shown to alter the rate of glucose absorption and subsequent glycemia and insulinemia. At this stage, systematic documentation of the differences that exist among carbohydrate foods was considered essential. The resulting glycemic index classification of foods provided a numeric physiologic classification of relevant carbohydrate foods in the prevention and treatment of diseases such as diabetes. Since then, low-glycemic-index diets have been shown to lower urinary C-peptide excretion in healthy subjects, improve glycemic control in diabetic subjects, and reduce serum lipids in hyperlipidemic subjects. Furthermore, consumption of low-glycemicindex diets has been associated with higher HDL-cholesterol concentrations and, in large cohort studies, with decreased risk of developing diabetes and cardiovascular disease. Case-control studies have also shown positive associations between dietary glycemic index and the risk of colon and breast cancers. Despite inconsistencies in the data, sufficient, positive findings have emerged to suggest that the dietary glycemic index is of potential importance in the treatment and prevention of chronic diseases.

    View details for Web of Science ID 000176378500038

    View details for PubMedID 12081850