Webster et al.

BMC Medicine (2022) 20:275

https://doi.org/10.1186/s12916-022-02468-0

RESEARCH ARTICLE Open Access

Risk of hip fracture in meat‑eaters,

pescatarians, and vegetarians: results
from the UK Women’s Cohort Study
James Webster1* , Darren C. Greenwood2† and Janet E. Cade1†

Abstract
Background: The risk of hip fracture in women on plant-based diets is unclear. We aimed to investigate the risk
of hip fracture in occasional meat-eaters, pescatarians, and vegetarians compared to regular meat-eaters in the UK
Women’s Cohort Study and to determine if potential associations between each diet group and hip fracture risk are
modified by body mass index (BMI).
Methods: UK women, ages 35–69 years, were classified as regular meat-eaters (≥ 5 servings/week), occasional meat-
eaters (< 5 servings/week), pescatarian (ate fish but not meat), or vegetarian (ate neither meat nor fish) based on a
validated 217-item food frequency questionnaire completed in 1995–1998. Incident hip fractures were identified via
linkage to Hospital Episode Statistics up to March 2019. Cox regression models were used to estimate the associations
between each diet group and hip fracture risk over a median follow-up time of 22.3 years.
Results: Amongst 26,318 women, 822 hip fracture cases were observed (556,331 person-years). After adjustment for
confounders, vegetarians (HR (95% CI) 1.33 (1.03, 1.71)) but not occasional meat-eaters (1.00 (0.85, 1.18)) or pescatar-
ians (0.97 (0.75, 1.26)) had a greater risk of hip fracture than regular meat-eaters. There was no clear evidence of effect
modification by BMI in any diet group (p-interaction = 0.3).
Conclusions: Vegetarian women were at a higher risk of hip fracture compared to regular meat-eaters. Further
research is needed to confirm this in men and non-European populations and to identify factors responsible for the
observed risk difference. Further research exploring the role of BMI and nutrients abundant in animal-sourced foods is
recommended.
Trial registration: Clini​calTr​ials.​gov, NCT05​081466
Keywords: Diet, Nutrition, Vegetarian, Hip fracture, Cohort study

Background Health-related quality of life declines after hip fracture

Hip fractures are most common in elderly women [1] and mortality increases [1, 4]. Social and economic
and are becoming increasingly prevalent in the UK costs from hip fractures are also substantial [2], with
and globally due to growing ageing populations [2, 3]. an international average cost 12 months after the first
hip fracture of $44,000 per patient [5]. There are grow-
†
ing concerns regarding bone health and fracture risk in
Darren C. Greenwood and Janet E. Cade contributed equally to this work.
individuals on meat-free diets [6–9], but associations
*Correspondence: sp16jw@leeds.ac.uk between these diet groups and hip fracture risk remain
1
Nutritional Epidemiology Group, School of Food Science and Nutrition, unclear. An estimated 5% of the US population [10],
University of Leeds, Leeds LS2 9JT, UK
3% of the UK population [11, 12], and 30% of India’s
Full list of author information is available at the end of the article

© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which
permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the
original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or
other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line
to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory
regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this
licence, visit http://​creat​iveco​mmons.​org/​licen​ses/​by/4.​0/. The Creative Commons Public Domain Dedication waiver (http://​creat​iveco​
mmons.​org/​publi​cdoma​in/​zero/1.​0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
Webster et al. BMC Medicine (2022) 20:275 Page 2 of 10

population follow vegetarian diets [13]. The number of fracture in occasional meat-eaters, pescatarians, and
vegetarians worldwide is increasing [7], possibly due vegetarians compared to regular meat-eaters in middle-
to accumulating evidence of reduced risks of several aged UK women and to determine if potential associa-
chronic diseases, including diabetes [14], ischaemic tions between each diet group and hip fracture risk are
heart disease, and cancer [15], and a lower environmen- modified by BMI.
tal footprint of vegetarian diets compared to omnivo-
rous diets [16, 17]. Understanding hip fracture risk in Methods
vegetarians in particular is therefore becoming increas- We followed the Strengthening the Reporting of Obser-
ingly important to public health. vational Studies in Epidemiology – Nutritional Epide-
Whilst diet quality varies among vegetarians [16], miology (STROBE-nut) guidelines for the reporting of
vegetarian diets are often characterised by a higher cohort studies (Additional file 1: Table S1) [28].
intake of fruits and vegetables including foods high
in vegetable protein [8], which have been associated Study design and participants
with a reduced hip fracture risk in adults in reviews The UKWCS has been described in detail elsewhere [27].
of previous epidemiological studies [18–21]. How- In brief, 500,000 women from England, Scotland, and
ever, vegetarian diets have also been characterised by Wales responded to a direct mail questionnaire from
lower dietary intakes of nutrients that have been posi- the World Cancer Research Fund (WCRF) between
tively associated with bone mineral density (BMD) 1995 and 1998. Of the 75% that agreed to participate in
and are more abundant in animal products than in a more detailed survey, those who identified as vegetar-
plants. Examples include total protein, calcium, vita- ian or non-red meat-eaters, and were aged 35–69 years
min D, vitamin B12, and ω-3 fatty acids [6, 22], though when completing the WCRF questionnaire, were eli-
associations between these nutrients and hip fracture gible for inclusion in the UKWCS. For each vegetarian,
risk are unclear and complex [20]. Studies have also the next non-vegetarian or red meat-eater who was aged
reported a lower average body mass index (BMI) in within 10 years of the vegetarian was selected to form
vegetarians and pescatarians compared to omnivores a comparison group. In total, 35,372 women across the
[8, 23], which has been inversely associated with hip UK, aged 35–69 years, responded to a postal question-
fracture risk [24]. Risk differences for hip fracture naire that collected dietary, lifestyle, demographic, and
between vegetarians, pescatarians, and meat-eaters anthropometric data at recruitment (1995–1998). This
are therefore plausible, but evidence is limited in approach was taken to maximise power in comparing the
exploring these dietary patterns. risk of hip fracture across the diet groups [29]. Partici-
Cross-sectional studies show lower BMD in vegetari- pants were then excluded if they lived outside of England
ans compared to non-vegetarians [25, 26], but prospec- (n = 3821), had a hip fracture on or before the date of
tive studies comparing the risk of hip fracture in these recruitment according to hospital episode statistics (n =
diet groups over time are scarce and limited [8, 9]. The 2), had missing age data (n = 364), or had outlier FFQ or
recently published European Prospective Investigation covariate data (daily energy intake < 500 kcal or > 5000
into Cancer (EPIC)-Oxford cohort study of UK men kcal, BMI < 10 or > 60 kg/m2, or FFQ intakes > 3 stand-
and women showed a greater risk of hip fracture in pes- ard deviations from the mean; n = 941), leaving 30,244
catarians, vegetarians, and vegans compared to meat- participants potentially eligible for inclusion in this study
eaters [8]. The Adventist Health Study-2 (AHS-2) also (Additional file 1: Fig. S1). Ethical approval was granted
showed a greater risk of hip fracture in vegans but not from the National Research Ethics Service Commit-
vegetarians compared to meat-eaters in US women, but tee for Yorkshire & the Humber – Leeds East (reference
with outcome data based on self-administered ques- 15/YH/0027) at the cohort’s inception in 1993 and was
tionnaires [9]. To our knowledge, no other prospective updated to include linkage outcomes, such as hip fracture
study has compared the risk of hip fracture in veg- incidence, in 2017 (reference 17/YH/0144).
etarians and non-vegetarians; therefore, associations
between these diet groups and hip fracture risk require Diet group
further investigation. Dietary habits of cohort participants over 12 months were
The United Kingdom Women’s Cohort Study assessed at recruitment using a self-administered 217-item
(UKWCS) has been enriched with vegetarians and pes- food frequency questionnaire (FFQ). The FFQ was vali-
catarians, so is well-suited to study the risk of chronic dated by comparison with 4-day weighed food diaries and
diseases over time in these diet groups [27]. Our a repeated FFQ on 283 women, both administered 3 years
objectives were therefore to investigate the risk of hip after baseline [27]. Based on the responses to questions on
Webster et al. BMC Medicine (2022) 20:275 Page 3 of 10

meat, fish, eggs, and dairy intakes, participants were clas- single/widowed); menopausal status (premenopau-
sified as regular meat-eaters (ate meat ≥ 5 times/week), sal, postmenopausal); number of children (continu-
occasional meat-eaters (ate meat < 5 times/week), pes- ous); prevalence of cardiovascular disease, cancer, or
catarians (ate fish but not meat), vegetarians (ate eggs or diabetes at recruitment (yes, no); physical activity in
dairy but not meat or fish), or vegans (did not eat meat, hours per day (continuous); smoking status (current,
fish, eggs, or dairy). Vegans were combined with the vege- former, never); alcohol consumption (> 1/week, ≤ 1/
tarian group due to the small number of vegan participants week, never); BMI (continuous); and any nutritional
(n = 130) and cases (n = 5). Participants with intakes of supplement use (yes, no). The DAG and definitions of
a food item of less than once per month were considered confounders are given in Additional file 1: Supplemen-
non-consumers. Further details on the questionnaire and tary methods, Table S3, and Fig. S2. The proportional
classification of diet groups are provided in Additional hazards assumption was assessed based on Schoen-
file 1: Supplementary methods and Table S2. feld residuals and was not violated for all terms in the
adjusted model.
Outcome To determine the role of BMI as a potential effect
Participants’ diet and lifestyle characteristics were linked modifier, we added dichotomized BMI level (< 23.5, ≥
with their hospital episode statistics up to 31 March 2019. 23.5 kg/m2) to the adjusted model as an interaction term
The primary outcome was hip fracture incidence (Interna- with each diet group, with these cut-off points defined
tional Classification of Diseases, ICD-9 code 820, ICD-10 to ensure a similar number of participants in each stra-
codes S72.0–72.2, Table S3). We also used hip replace- tum. We also added individual BMI (continuous per kg/
ments (ICD-10 code Z96.64) as an indicator of hip frac- m2 increase) to the adjusted model as an interaction term
ture, but no additional cases were identified using these with each diet group and omitted BMI from the adjust-
criteria. The time frame was person-years until hip frac- ment set for that analysis. Further exploratory analyses
ture incidence, or until the end of the study period or death included testing for interaction effects with each diet
in non-cases, using attained age as the timescale [30]. group for menopausal status (premenopausal, postmen-
opausal), physical activity level (< 150 minutes/week,
Statistical analysis ≥ 150 min/week), age (≤ 60, > 60 years), SES (routine/
All statistical methods were registered in advance on manual, intermediate, professional/managerial), smoking
Clini​calTr​ials.​gov (NCT05081466). status (current, former, never), and use of any nutritional
Socio-demographic, lifestyle, anthropometric, and nutri- supplements (yes, no). In each exploratory subgroup
tional characteristics of UKWCS participants at recruit- analysis, the potential effect modifier was omitted from
ment were summarised by diet group using descriptive the relevant adjustment set.
statistics. Cox proportional hazard regression models were We explored the effect of potential mediators by fur-
fitted to estimate hazard ratios (HR) and 95% confidence ther adjusting the adjusted model for each mediator
intervals (95% CI) for the associations between each diet independently. Potential mediators were total energy
group and hip fracture risk, with regular meat-eaters as intake and intake of protein, calcium, vitamin D, vitamin
the reference group. The target estimand was the relative B12, monounsaturated fatty acids (MUFA), polyunsatu-
causal effect of each diet group on hip fracture risk com- rated fatty acids (PUFA), and zinc from dietary sources
pared to regular meat-eaters. Cox models used weights only (not including supplemental sources). An adjusted
based on the inverse probability of being sampled to model with BMI removed from the adjustment set is also
account for the over-sampling of pescatarians and vegetar- presented to determine its influence on any associations.
ians at recruitment, increasing the representativeness of As a sensitivity analysis, we explored the risk of hip
the cohort to the UK population [29]. fracture in vegans compared to meat-eaters by fitting the
We applied both unadjusted and multivariable- adjusted model with vegetarians and vegans separated.
adjusted models. Both models controlled for age by Additional sensitivity analyses were as follows: excluding
using attained age as the timescale [30]. Additional participants with a survival time < 5 years to check for
confounders included in the adjusted model were based reverse causation, excluding participants on long-term
on a directed acyclic graph (DAG), following available treatment for illness, and further adjusting for hormone
guidelines on their creation and reporting [31], and replacement therapy (HRT) and prevalence of fracture
included (all at recruitment): ethnicity (white, Asian, at sites other than the hip at recruitment (identified in
black, other); socio-economic status (SES, professional/ hospital episode statistics), respectively, since these are
managerial, intermediate, routine/manual); marital known risk factors for hip fracture [32]. Participants with
status (married/living as married, separated/divorced, missing data for a variable required in a given analysis
Webster et al. BMC Medicine (2022) 20:275 Page 4 of 10

were excluded from that analysis. We did not impute 811), physical activity (n = 1561), marital status (n =
missing covariate data. All statistical analyses were per- 460), SES (n = 331), or menopausal status (n = 309)
formed using Stata (version 17). were excluded, leaving 26,318 women for unadjusted
and adjusted analyses. The study flow chart is given in
Results Additional file 1: Fig. S1.
Participants
Of the 30,244 women potentially eligible at recruit- Descriptive data
ment, those with missing covariate data for body Characteristics of the 26,318 cohort participants at
weight (n = 596), height (n = 649), ethnicity (n = recruitment are summarised by diet group in Table 1.

Table 1 Characteristics of 26,318 UKWCS participants at recruitment by diet group

Characteristics, mean (SD) or n (%) Total Diet group
Regular meat-eater Occasional meat-eater Pescatarian Vegetarian

Participants (%) 26,318 13,984 (46.2) 8000 (26.5) 3867 (12.8) 4393 (14.5)
Cases (%) 822 (3.1) 394 (3.2) 247 (3.6) 80 (2.4) 101 (2.6)
Socio-demographics
Age, years (SD) 52.1 (9.2) 53.3 (9.2) 53.2 (9.4) 49.7 (8.5) 48.3 (8.2)
Degree-level education (%) 6502 (26.8) 2306 (20.7) 1780 (28.2) 1143 (35.9) 1273 (35.1)
Socioeconomic status (%)
   Professional or managerial 19,057 (72.4) 8518 (69.7) 5120 (74.2) 2576 (76.3) 2843 (74.5)
  Intermediate 2440 (9.3) 1117 (9.1) 694 (10.1) 270 (8.0) 359 (9.4)
   Routine or manual 4821 (18.3) 2586 (21.2) 1088 (15.8) 531 (15.7) 616 (16.1)
Married (%) 20,268 (77.0) 10,103 (82.7) 5007 (72.5) 2432 (72.0) 2726 (71.4)
White ethnicity (%) 25,992 (98.8) 12,139 (99.3) 6820 (98.8) 3331 (98.6) 3702 (97.0)
Lifestyle
Exercise (h/day) 0.2 (0.5) 0.2 (0.5) 0.2 (0.4) 0.3 (0.5) 0.3 (0.5)
Smoking status (%)
  Current 3513 (13.3) 1678 (13.7) 921 (13.3) 448 (13.3) 466 (12.2)
  Former 7947 (30.2) 3519 (28.8) 2078 (30.1) 1161 (34.4) 1189 (31.1)
  Never 3110 (11.8) 7024 (57.5) 3903 (56.5) 1768 (52.4) 2163 (56.7)
Alcohol consumption (%)
   > 1 serving/week 13,918 (52.9) 6798 (55.6) 3548 (51.4) 1830 (54.2) 1742 (45.6)
  ≤ 1 serving/week 9290 (35.3) 4276 (35.0) 2471 (35.8) 1145 (33.9) 1398 (36.6)
  Never 3110 (11.8) 1147 (9.4) 883 (12.8) 402 (11.9) 678 (17.8)
Nutritional supplementation (%) 14,009 (53.2) 5902 (48.3) 3881 (56.2) 2070 (61.3) 2156 (56.5)
Anthropometrics
BMI, kg/m2 (SD) 24.4 (4.2) 25.3 (4.5) 24.1 (3.9) 23.3 (3.5) 23.3 (3.9)
Height, m (SD) 1.6 (0.1) 1.6 (0.1) 1.6 (0.1) 1.6 (0.1) 1.6 (0.1)
Dietary nutrient intakes
Energy intake, kcal/day (SD) 2300 (654.8) 2445 (640.3) 2069 (605.9) 2294 (656.3) 2259 (658.2)
Protein intake, g/day (SD) 88.1 (26.3) 100.9 (24.8) 77.5 (21.3) 79.6 (23.1) 74.0 (22.3)
≥ 0.75 g protein/kg body weight/day (%) 24,837 (94.4) 12,067 (98.7) 6262 (90.7) 3116 (92.3) 3392 (88.8)
Calcium intake, mg/day (SD) 1135 (365.4) 1163 (344.6) 1060 (356.3) 1183 (395.0) 1138 (398.0)
Vitamin D intake, μg/day (SD) 3.1 (1.7) 3.6 (1.6) 2.9 (1.6) 3.1 (1.8) 1.9 (1.1)
Vitamin B12 intake, μg/day (SD) 2.5 (1.2) 7.5 (2.9) 5.1 (2.2) 4.3 (2.0) 2.5 (1.2)
Others
Premenopausal (%) 11,707 (44.5) 7521 (61.5) 4114 (59.6) 1531 (45.3) 1445 (37.8)
Postmenopausal (%) 14,611 (55.5) 4700 (38.5) 2788 (40.4) 1846 (54.7) 2373 (62.2)
≥ 1 children (%) 20,723 (78.7) 10,263 (84.0) 5324 (77.1) 2468 (73.1) 2668 (69.9)
Prevalence of CVD, cancer, or diabetes (%) 2388 (9.1) 1250 (10.2) 664 (9.6) 252 (7.5) 222 (5.8)
SD standard deviation, SES social economic status, BMI body mass index
Webster et al. BMC Medicine (2022) 20:275 Page 5 of 10

Fig. 1 Risk of hip fracture in occasional meat-eaters, pescatarians, and vegetarians compared to regular meat-eaters in the UKWCS. The
multivariable-adjusted model was adjusted for the following (all at recruitment): ethnicity (white, Asian, black, other); socio-economic status
(professional/managerial, intermediate, routine/manual); marital status (married/living as married, separated/divorced, single/widowed);
menopausal status (premenopausal, postmenopausal); number of children (continuous); prevalence of cardiovascular disease, cancer, or diabetes
(yes, no); physical activity in hours per day (continuous); smoking status (current, former, never); alcohol consumption (> 1/week, ≤ 1/week, never);
BMI (continuous); and any nutritional supplement use (yes, no). HR (95% CI), hazard ratio (95% confidence interval)

Over a median follow-up time of 22.3 years, 822 hip or restricting to participants with missing covariate data
fracture cases were observed (556,331 person-years), (Additional file 1: Table S5).
corresponding to 3.1% of the cohort. On average, at
recruitment, pescatarians and vegetarians were younger Diet groups
than regular meat-eaters, reported higher education lev- Compared with regular meat-eaters, vegetarians (HR
els, were more likely to have professional or managerial 1.40 (95% CI 1.11, 1.78)) but not occasional meat-eaters
jobs and less likely to have routine or manual jobs, and (1.03 (0.88, 1.21)) or pescatarians (1.04 (0.81, 1.34)) had
were less likely to be married or have any children. BMI a greater risk of hip fracture in the unadjusted model
was lower in vegetarians (mean (standard deviation, SD) (Fig. 1). Adjustment for confounders slightly attenuated
23.3 (3.9 kg/m2)) and pescatarians (23.3 (3.5 kg/m2)) than these associations in the adjusted model, but the higher
in regular meat-eaters (25.2 (4.4 kg/m2)). Prevalence of risk in vegetarians remained and was statistically signifi-
CVD, cancer, or diabetes at recruitment was highest in cant (vegetarians 1.33 (1.03, 1.71); occasional meat-eaters
regular meat-eaters (n = 1250 (10.2%)), and lowest in 1.00 (0.85, 1.18); pescatarians 0.97 (0.75, 1.26)).
vegetarians (222 (5.8%)). Exercise and smoking habits
were similar across diet groups, but a higher proportion Subgroup analyses
of vegetarians reported never drinking alcohol than all Whilst the risk of hip fracture was 46% higher in partici-
other diet groups. Regular meat-eaters reported the high- pants with BMI < 23.5 kg/m2 compared to BMI ≥ 23.5
est absolute dietary intakes of protein, vitamin D, and kg/m2, there was no evidence of effect modification by
vitamin B12, whilst vegetarians reported the lowest. Cal- BMI on hip fracture risk in each diet group when BMI
cium intakes were similar across the diet groups. Other was modelled categorically (p-interaction = 0.3) or lin-
food and nutrient intakes in each diet group are sum- early (p-interaction = 0.6) (Table 2). There was also no
marised in Additional file 1: Table S4. Characteristics of evidence of effect modification in any diet group by age,
the cohort at recruitment were similar when including physical activity, nutritional supplementation, SES, or

Table 2 Risk of hip fracture in occasional meat-eaters, pescatarians, and vegetarians compared to regular meat-eaters by BMI in the
UKWCS
Stratifying variable n cases/participants, adjusted HR (95% CI)
BMI < 23.5 kg/m2 ≥ 23.5 kg/m2 p interaction

Regular meat-eaters (reference) 161/4927 1.00 233/7294 1.00

Occasional meat-eaters 123/3554 0.96 (0.75, 1.21) 124/3348 1.05 (0.84, 1.31)
Pescatarians 50/2075 0.90 (0.65, 1.25) 30/1302 1.06 (0.71, 1.60)
Vegetarians 72/2338 1.49 (1.10, 2.03) 29/1480 1.02 (0.66, 1.58) 0.3
Models were adjusted for the following (all at recruitment): ethnicity (white, Asian, black, others); socio-economic status (SES, professional/managerial, intermediate,
routine/manual); marital status (married/living as married, separated/divorced, single/widowed); menopausal status (premenopausal, postmenopausal); number
of children (continuous); prevalence of cardiovascular disease, cancer, or diabetes (yes, no); physical activity in hours per day (continuous); smoking status (current,
former, never); alcohol consumption (> 1/week, ≤ 1/week, never); BMI (continuous), and any nutritional supplement use (yes, no)
HR (95% CI) hazard ratio (95% confidence interval), BMI body mass index
Webster et al. BMC Medicine (2022) 20:275 Page 6 of 10

smoking status (Additional file 1: Table S6). There was Considering vegetarians (96 cases/3688 participants) and
some evidence of effect modification by menopausal sta- vegans (5 cases/130 participants) separately did not sub-
tus, where occasional meat-eaters were at a reduced risk stantially alter the estimates in vegetarians (vegetarians
of hip fracture in premenopausal women only (0.43 (0.21, 1.38 (1.07, 1.78) and vegans 1.10 (0.42, 2.84)).
0.86), p-interaction = 0.05).
Discussion
Sensitivity analyses Principal findings
The risk of hip fracture appeared higher without adjust- Vegetarians but not occasional meat-eaters or pescatar-
ment for BMI in vegetarians (1.43 (1.12, 1.83); Table 3). ians were at a higher risk of hip fracture than regular
Further adjusting the adjusted model for dietary vita- meat-eaters in this cohort of UK women. There was no
min D intake in vegetarians increased the magnitude clear evidence of effect modification by BMI across diet
of the association with hip fracture risk (1.44 (1.10, groups. The risk differences remained after accounting
1.87)), whilst further adjustment for dietary MUFA for confounders and were not explained by differences in
intake increased the strength of associations for occa- key nutrient intakes related to bone health between veg-
sional meat-eaters (1.07, 0.90, 1.27)) and vegetar- etarians and regular meat-eaters, implying the potential
ians (1.39 (1.08, 1.79)) (Table 3). Further adjustment for importance of other unaccounted factors.
total energy intake and dietary intake of protein, cal-
cium, vitamin B12, and PUFAs did not alter the results Comparison with previous studies
substantially. Prospective evidence of hip fracture risk in individuals
All adjusted results were robust to the addition or on meat-free diets is limited. Our findings largely concur
removal of other individual covariates from the model, with the results of the only other two cohort studies on
with estimates remaining broadly unchanged across most this topic [8, 9], strengthening the evidence of a higher
sensitivity analyses (Additional file 1: Table S7). Exclu- risk of hip fracture in UK vegetarian women.
sion of participants on long-term treatment for illness In the EPIC-Oxford cohort, there was evidence of
slightly increased the magnitude of associations in all a higher risk of hip fracture in vegetarian women of a
diet groups (occasional meat-eaters 1.09 (0.88, 1.37); pes- similar magnitude (25%) [8]. The slightly higher effect
catarians 1.08 (0.78, 1.50); vegetarians:1.48 (1.07, 2.04)). estimate in our study (33%) may be due to our reference

Table 3 Risk of hip fracture in occasional meat-eaters, pescatarians, and vegetarians compared to regular meat-eaters in the UKWCS,
with varying levels of adjustment
Model ± further adjustments HR (95% CI) per diet group
Regular meat-eaters Occasional meat-eaters Pescatarians Vegetarians
(reference)

Model ­1a 1.00 1.03 (0.88, 1.21) 1.04 (0.81, 1.34) 1.40 (1.11, 1.78)
Model ­2b 1.00 1.00 (0.85, 1.18) 0.97 (0.75, 1.26) 1.33 (1.03, 1.71)
Model 2 − BMI 1.00 1.05 (0.89, 1.24) 1.05 (0.81, 1.35) 1.43 (1.12, 1.83)
Potential mediators 1.00
Model 2 + total energy 1.00 1.05 (0.89, 1.24) 0.99 (0.76, 1.28) 1.36 (1.06, 1.75)
Model 2 + dietary protein 1.00 1.03 (0.86, 1.23) 0.99 (0.76, 1.29) 1.36 (1.05, 1.78)
Model 2 + dietary calcium 1.00 1.01 (0.86, 1.20) 0.97 (0.75, 1.25) 1.33 (1.04, 1.72)
Model 2 + dietary vitamin D 1.00 1.03 (0.87, 1.22) 0.99 (0.77, 1.29) 1.44 (1.10, 1.87)
Model 2 + dietary vitamin B12 1.00 1.01 (0.85, 1.22) 0.98 (0.75, 1.30) 1.36 (1.01, 1.82)
Model 2 + dietary MUFA 1.00 1.07 (0.90, 1.27) 1.00 (0.77, 1.30) 1.39 (1.08, 1.79)
Model 2 + dietary PUFA 1.00 1.03 (0.87, 1.21) 0.96 (0.74, 1.24) 1.32 (1.02, 1.69)
Model 2 + dietary zinc 1.00 1.01 (0.85, 1.21) 0.97 (0.75, 1.27) 1.34 (1.03, 1.73)
HR (95% CI) hazard ratio (95% confidence interval), MUFA monounsaturated fatty acids, PUFA polyunsaturated fatty acids
a
Model 1 included 26,318 participants and was unadjusted
b
Model 2 included 26,318 participants and was adjusted for ethnicity (white, Asian, black, other), socio-economic status (SES, professional/managerial, intermediate,
routine/manual), marital status (married/living as married, separated/divorced, single/widowed), menopausal status (premenopausal, postmenopausal), number of
children (continuous), chronic disease prevalence at baseline (yes, no—including stroke, cancer, or diabetes), physical activity in hours per day (continuous), smoking
status (current, former, never), alcohol consumption (> 1/week, ≤ 1/week, never), body mass index (BMI, continuous), and any nutritional supplement use (yes, no). All
other models were based on the 26,318 participants in model 2
Webster et al. BMC Medicine (2022) 20:275 Page 7 of 10

group being regular meat-eaters, whereas the reference diet groups. Whilst there was no clear evidence of BMI
group in the EPIC-Oxford cohort was meat-eaters of modifying associations between diet groups and hip
any amount. The AHS-2 also found limited evidence of fracture risk, the lower mean BMI in vegetarians partly
a 17% higher risk of hip fracture in US vegetarian women explained their higher risk. Previous studies have shown
[9]. Differences in estimates between the AHS-2 and our BMI and body weight to be lower in vegetarians [26,
results may be due to the different adjustment strate- 36], and inversely associated with hip fracture risk [24,
gies when accounting for confounders; in the AHS-2, 37]. Possible mechanisms include the protective roles of
attained age was used as the time frame, and adjustment bone mass, fat mass, and muscle mass, which have each
was made for age and energy, calcium, potassium, and been inversely associated with hip fracture risk indepen-
vitamin D intakes at recruitment amongst other factors. dently [38]. Inadequate fat mass may reduce cushioning
This may have resulted in overadjustment and adjust- from impact force at the hip during falls, which account
ment for factors potentially on the causal pathway, dilut- for 90% of hip fractures [39]. Higher fat mass could also
ing risk estimates. The AHS-2 also relied on self-report increase bone strength through increased mechani-
for case ascertainment. We identified hip fracture cases cal loading and enhanced oestrogen production [38].
using participants’ hospital episode statistics, which Low muscle mass and strength of the hip flexor mus-
incurs less reporting error and selective loss to follow-up. cles and spine extensors have also been associated with
We found no clear evidence of a difference in hip fracture an increased risk of hip fracture [40], possibly due to
risk in pescatarians or occasional meat-eaters (ate meat reduced balance and mobility. Weight management may
< 5 times/week) compared to regular meat-eaters. Simi- therefore be an important consideration in reducing
larly, in the AHS-2, there was no clear evidence of a dif- hip fracture risk in vegetarians, but further research is
ference in hip fracture risk in semi-vegetarian (ate meat required to explore the roles of BMI and body composi-
or fish ≤ once/week) or pescatarian women compared to tion in hip fracture risk in vegetarians and meat-eaters.
non-vegetarians [9]. In contrast, the EPIC-Oxford cohort A second potential reason for the higher risk of hip frac-
study found a 30% increased risk in pescatarian women, ture in vegetarians is their lower intake of nutrients impor-
potentially due to population differences between EPIC- tant to bone health that are abundant in animal products.
Oxford and the UKWCS, different intakes of fish or Previous studies have found lower dietary intakes of pro-
other dietary components, or other sources of residual tein, calcium, vitamin D, and vitamin B12 in vegetarians
confounding in either study [8]. Both the EPIC-Oxford [6, 22], and have suggested protective associations of these
and AHS-2 cohort studies reported higher risks of hip nutrients with hip fracture risk [6, 41, 42]. In our study,
fracture in vegans compared to meat-eaters [8, 9]. Due vegetarians had lower dietary intakes of protein, vitamin
to the low number of vegans in the UKWCS, we could D, and vitamin B12, but similar dietary calcium intakes to
not precisely estimate their risk of hip fracture separate other diet groups. In particular, vegetarians were less likely
from the vegetarian group. Since vegans may face greater to meet the UK recommendation for protein intake in
challenges in achieving adequate intake of several nutri- adults of 0.75 g/kg body weight/day than regular meat-eat-
ents, in particular protein and calcium [6], cohort studies ers (88.8% vs 98.3%) [43], but the higher risk of hip fracture
with a high proportion of vegans are needed investigating in vegetarians was not explained by any dietary nutrient
their risk of hip fracture. intake. It is likely that measurement error incurred by esti-
Other epidemiological studies have found that adher- mating nutrient intakes from an FFQ precluded accurate
ence to diets low in meat consumption, such as the estimation of the importance of nutrients from dietary
Mediterranean diet and Alternative Healthy Eating sources to hip fracture risk in vegetarians.
Index, was protectively associated with hip fracture risk Since the higher risk of hip fracture in vegetarians
[33, 34], and adherence to Western diets in which meat remained after adjustment for BMI and several dietary
consumption is high was positively associated with hip nutrient intakes, other factors may be important. Supple-
fracture risk [35]. Conversely, total meat intake has been mental sources of specific nutrients and circulating vita-
inversely associated with hip fracture risk [21]. These min D concentrations could differ between vegetarians
results cannot be fairly compared with risks in vegetar- and non-vegetarians and may impact the risk of hip frac-
ians and non-vegetarians, which no other study has ture [9, 44] but could not be accounted for in this analy-
directly assessed. sis due to a lack of data. Circulating levels of insulin-like
growth factor-1 (IGF-1) may also be lower in vegetarians
Interpretation and implications than in non-vegetarians [45] and have been positively
The observed higher risk of hip fracture in vegetarians associated with BMD and negatively associated with risk
compared to regular meat-eaters may be partly explained of total fracture and hip fracture [46], but could not be
by the differences in body anthropometrics between the considered here. Future studies should investigate the
Webster et al. BMC Medicine (2022) 20:275 Page 8 of 10

roles of IGF-1 and nutrients abundant in animal products fracture history. The single questionnaire adminis-
on hip fracture risk in vegetarians to better understand tered at recruitment was the only method of assess-
the reasons for their observed higher risk. ing diet and lifestyle information; therefore, we could
not account for changes in the diet group or covari-
Strengths and limitations
ates over time. Additionally, food and nutrient intake
This study has three main strengths. Firstly, the large in vegetarians in recent years could differ from when
number of pescatarians and vegetarians included gave data were collected at recruitment due to changes
good statistical power to estimate their risk of hip frac- over the last two decades in the availability of vegetar-
ture. Secondly, the identification of hip fractures based ian food products, such as increases in the number of
on hospital records over a long follow-up period reduced available meat substitute products [49]. Consequently,
reporting errors and loss to follow-up. Finally, we classi- the generalisability of our findings to modern-day
fied subjects into diet groups based on reported intakes vegetarians is reduced. Our findings were also pre-
of animal foods using a validated FFQ, which may more dominantly in white UK women; previous studies have
accurately allocate participants into diet groups than ask- shown that total fracture risk could depend on ethnic-
ing participants to identify their diet group. ity [50]; therefore, more research is needed investigat-
On average, UKWCS participants were younger by ing hip fracture risk in non-European vegetarians and
end of follow-up than the average age at hip fracture in non-vegetarians.
women (83 years) [47], limiting the number of hip frac-
tures observed. Moreover, high-energy trauma may Conclusion
account for more hip fractures in younger adults, whereas Overall, vegetarians but not occasional meat-eaters or
fragility hip fractures are more common in older adults pescatarians were at a higher risk of hip fracture com-
[48]. We could not distinguish between traumatic and pared to regular meat-eaters in this cohort of UK women.
fragility fractures here since information on the cause Further research is needed to confirm this in other popu-
of hip fractures was not available. We had insufficient lations, such as men and non-European populations, and
power to detect effect modification by covariates in sub- to identify the factors responsible for the observed risk
group analyses. For BMI, the strong correlation with the difference. In particular, further research exploring the
diet group meant that the number of vegetarians with a roles of BMI and nutrients abundant in animal-sourced
high BMI or regular meat-eaters with a low BMI was low. foods is recommended so that public health interven-
Moreover, BMI was derived from self-reported height tions and policy guidelines aiming to reduce hip frac-
and body weight, implying a possible measurement error. ture risk in vegetarians through dietary change or weight
Investigation of hip fracture risk in underweight partici- management can be formed.
pants by diet group was also not possible but merits fur-
ther investigation. Abbreviations
Women with missing covariate data (n = 3926) were BMD: Bone mineral density; BMI: Body mass index; UKWCS: United Kingdom’s
Women’s Cohort Study; EPIC: European Prospective Investigation into Cancer
excluded from the analyses in this study, which intro- and Nutrition; AHS-2: Adventist Health Study-2; ICD: International Classification
duced a risk of selection bias. However, the magnitude of Diseases; IGF-1: Insulin-like growth factor-1; MUFA: Monounsaturated fatty
of any selection bias is unlikely to be clinically sig- acids; PUFA: Polyunsaturated fatty acids.
nificant, given that the characteristics of participants
included or excluded in analyses here at recruitment Supplementary Information
were similar (Additional file 1: Table S5). Although we The online version contains supplementary material available at https://​doi.​
org/​10.​1186/​s12916-​022-​02468-0.
adjusted for likely confounders, residual confounding
was possible. For example, we could not adjust for the Additional file 1: Figure S1. Flow chart of UKWCS participants. Figure
use of medications that could impact the associations S2. Directed Acyclic Graph showing the relationship between diet group,
between the diet groups and hip fracture risk due hip fracture incidence, and related factors. Table S1: Strengthening the
reporting of observational studies in nutritional epidemiology (STROBE-
to a lack of data. The risk of hip fracture could dif- Nut) checklist. Table S2: Diet group categorisation and definitions.
fer between moderate and heavy consumers of alco- Table S3: Covariates at recruitment and their derivation. Table S4: Further
hol [20], but we were unable to differentiate between dietary characteristics of UKWCS participants by diet group at recruitment.
Table S5: Characteristics of UKWCS participants at recruitment that were
these groups when adjusting for alcohol consumption. included or excluded from adjusted analyses. Table S6: Risk of hip fracture
In addition, the exclusion of participants with prior in occasional meat-eaters, pescatarians, and vegetarians compared to
hip fractures was likely an incomplete exclusion, since regular meat-eaters stratified by potential effect modifiers in the UKWCS.
Table S7: Risk of hip fracture by diet group with varying restrictions in the
hospital data of fracture incidences before 1997 was UKWCS. Supplementary methods.
not available, and the questionnaire did not ask about
Webster et al. BMC Medicine (2022) 20:275 Page 9 of 10

10. Le LT, Sabaté J. Beyond meatless, the health effects of vegan diets: find-
Acknowledgements ings from the Adventist cohorts. Nutrients. 2014;6(6):2131–47.
We thank the women who participated in the UK Women’s Cohort Study. 11. Foods Standards Agency. National diet and nutrition survey: head-
line results from Years 1 and 2 (combined) of the Rolling Programme
Authors’ contributions (2009/2009 - 2009/10). 2012.
JC and DCG conceived and supervised the work. JW analysed the data and 12. Benson A, Irdam D, Bulceag I, Barber T, Draper A. Food and you survey:
wrote the initial draft. All authors provided input on the study design, data wave 5 secondary analysis: the current food landscape across England,
analysis, and interpretation of the results; revised the paper critically for impor- Wales, and Northern Ireland. Foods Standards Agency; 2019.
tant intellectual content; and approved the final version. 13. Shridhar K, Dhillon PK, Bowen L, Kinra S, Bharathi AV, Prabhakaran D, et al.
Nutritional profile of Indian vegetarian diets--the Indian Migration Study
Funding (IMS). Nutr J. 2014;13:55.
The authors received no specific funding for this work, though JW is in receipt 14. Lee Y, Park K. Adherence to a vegetarian diet and diabetes risk: a sys-
of a scholarship from the School of Food Science and Nutrition, University of tematic review and meta-analysis of Observational Studies. Nutrients.
Leeds, and Rank Prize Funds. 2017;9(6):603.
15. Dinu M, Abbate R, Gensini GF, Casini A, Sofi F. Vegetarian, vegan diets
Availability of data and materials and multiple health outcomes: a systematic review with meta-analysis of
The data access policy for the UK Women’s Cohort Study is available via the observational studies. Crit Rev Food Sci Nutr. 2017;57(17):3640–9.
study website (The UK Women​’s Cohor​t Study​(UKWCS)​:​Unive​rsity​of Leeds). 16. Rosi A, Mena P, Pellegrini N, Turroni S, Neviani E, Ferrocino I, et al. Environ-
mental impact of omnivorous, ovo-lacto-vegetarian, and vegan diet. Sci
Declarations Rep. 2017;7(1):6105.
17. Fresán U, Sabaté J. Vegetarian diets: planetary health and its alignment
Ethics approval and consent to participate with human health. Adv Nutr. 2019;10(Suppl_4):S380–s8.
Ethical approval was granted from the National Research Ethics Service Com- 18. Luo S, Li Y, Luo H, Yin X, Lin du R, Zhao K, et al. Increased intake of vegeta-
mittee for Yorkshire & the Humber – Leeds East (reference 15/YH/0027) at the bles, but not fruits, may be associated with reduced risk of hip fracture: a
cohort’s inception in 1993 and was updated to include linkage outcomes, meta-analysis. Sci Rep. 2016;6:19783.
such as hip fracture incidence, in 2017 (reference 17/YH/0144). 19. Brondani JE, Comim FV, Flores LM, Martini LA, Premaor MO. Fruit and
vegetable intake and bones: a systematic review and meta-analysis. PLoS
Consent for publication One. 2019;14(5):e0217223.
Not applicable. 20. Webster J, Rycroft CE, Greenwood DC, Cade JE. Dietary risk factors for hip
fracture in adults: an umbrella review of meta-analyses of prospective
Competing interests cohort studies. PLoS One. 2021;16(11):e0259144.
The authors declare that they have no competing interests. 21. Lousuebsakul-Matthews V, Thorpe DL, Knutsen R, Beeson WL, Fraser GE,
Knutsen SF. Legumes and meat analogues consumption are associated
Author details with hip fracture risk independently of meat intake among Caucasian
1
Nutritional Epidemiology Group, School of Food Science and Nutrition, Uni- men and women: the Adventist Health Study-2. Public Health Nutr.
versity of Leeds, Leeds LS2 9JT, UK. 2 School of Medicine, University of Leeds, 2014;17(10):2333–43.
Leeds LS2 9JT, UK. 22. Davey GK, Spencer EA, Appleby PN, Allen NE, Knox KH, Key TJ. EPIC-
Oxford: lifestyle characteristics and nutrient intakes in a cohort of 33 883
Received: 21 April 2022 Accepted: 7 July 2022 meat-eaters and 31 546 non meat-eaters in the UK. Public Health Nutr.
2003;6(3):259–69.
23. Bradbury KE, Tong TYN, Key TJ. Dietary intake of high-protein foods and
other major foods in meat-eaters, poultry-eaters, fish-eaters, vegetarians,
and vegans in UK Biobank. Nutrients. 2017;9(12):1317.
24. Armstrong ME, Cairns BJ, Banks E, Green J, Reeves GK, Beral V. Different
References
effects of age, adiposity and physical activity on the risk of ankle, wrist
1. Dhanwal DK, Dennison EM, Harvey NC, Cooper C. Epidemiology of hip frac-
and hip fractures in postmenopausal women. Bone. 2012;50(6):1394–400.
ture: worldwide geographic variation. Indian J Orthop. 2011;45(1):15–22.
25. Ho-Pham LT, Nguyen ND, Nguyen TV. Effect of vegetarian diets on
2. Veronese N, Maggi S. Epidemiology and social costs of hip fracture. Injury.
bone mineral density: a Bayesian meta-analysis. Am J Clin Nutr.
2018;49(8):1458–60.
2009;90(4):943–50.
3. Jennison T, Brinsden M. Fracture admission trends in England over a ten-
26. Tong TY, Key TJ, Sobiecki JG, Bradbury KE. Anthropometric and physi-
year period. Ann R Coll Surg Engl. 2019;101(3):208–14.
ologic characteristics in white and British Indian vegetarians and nonveg-
4. Peraza-Delgado A, Sánchez-Gómez MB, Gómez-Salgado J, Romero-Mar-
etarians in the UK Biobank. Am J Clin Nutr. 2018;107(6):909–20.
tín M, Novo-Muñoz M, Duarte-Clíments G. Non-pharmacological inter-
27. Cade JE, Burley VJ, Alwan NA, Hutchinson J, Hancock N, Morris MA, et al.
ventions towards preventing the triad osteoporosis-falls risk-hip fracture,
Cohort profile: the UK Women’s Cohort Study (UKWCS). Int J Epidemiol.
in population older than 65. Scoping Review. J Clin Med. 2020;9(8):2329.
2017;46(2):e11.
5. Williamson S, Landeiro F, McConnell T, Fulford-Smith L, Javaid MK, Judge
28. Lachat C, Hawwash D, Ocké MC, Berg C, Forsum E, Hörnell A, et al.
A, et al. Costs of fragility hip fractures globally: a systematic review and
Strengthening the Reporting of Observational Studies in Epidemiology-
meta-regression analysis. Osteoporos Int. 2017;28(10):2791–800.
Nutritional Epidemiology (STROBE-nut): an extension of the STROBE
6. Tucker KL. Vegetarian diets and bone status. Am J Clin Nutr.
Statement. PLoS Med. 2016;13(6):e1002036.
2014;100(Suppl 1):329s–35s.
29. Rada-Fernandez de Jauregui D, Evans CEL, Jones P, Greenwood DC,
7. Iguacel I, Miguel-Berges ML, Gómez-Bruton A, Moreno LA, Julián C.
Hancock N, Cade JE. Common dietary patterns and risk of cancers of the
Veganism, vegetarianism, bone mineral density, and fracture risk: a
colon and rectum: analysis from the United Kingdom Women’s Cohort
systematic review and meta-analysis. Nutr Rev. 2019;77(1):1–18.
Study (UKWCS). Int J Cancer. 2018;143(4):773–81.
8. Tong TYN, Appleby PN, Armstrong MEG, Fensom GK, Knuppel A, Papier
30. Korn EL, Graubard BI, Midthune D. Time-to-event analysis of longitu-
K, et al. Vegetarian and vegan diets and risks of total and site-specific
dinal follow-up of a survey: choice of the time-scale. Am J Epidemiol.
fractures: results from the prospective EPIC-Oxford study. BMC Med.
1997;145(1):72–80.
2020;18(1):353.
31. Tennant PWG, Murray EJ, Arnold KF, Berrie L, Fox MP, Gadd SC, et al.
9. Thorpe DL, Beeson WL, Knutsen R, Fraser GE, Knutsen SF. Dietary patterns
Use of directed acyclic graphs (DAGs) to identify confounders in
and hip fracture in the Adventist Health Study 2: combined vitamin D
applied health research: review and recommendations. Int J Epidemiol.
and calcium supplementation mitigate increased hip fracture risk among
2021;50(2):620–32.
vegans. Am J Clin Nutr. 2021;114(2):488–95.
Webster et al. BMC Medicine (2022) 20:275 Page 10 of 10

32. Benetos IS, Babis GC, Zoubos AB, Benetou V, Soucacos PN. Factors affect-
ing the risk of hip fractures. Injury. 2007;38(7):735–44.
33. Malmir H, Saneei P, Larijani B, Esmaillzadeh A. Adherence to Mediter-
ranean diet in relation to bone mineral density and risk of fracture: a
systematic review and meta-analysis of observational studies. Eur J Nutr.
2018;57(6):2147–60.
34. Panahande B, Sadeghi A, Parohan M. Alternative healthy eating index and
risk of hip fracture: a systematic review and dose-response meta-analysis.
J Hum Nutr Diet. 2019;32(1):98–107.
35. Fabiani R, Naldini G, Chiavarini M. Dietary patterns in relation to low bone
mineral density and fracture risk: a systematic review and meta-analysis.
Adv Nutr (Bethesda). 2019;10(2):219–36.
36. Barnard ND, Levin SM, Yokoyama Y. A systematic review and meta-analy-
sis of changes in body weight in clinical trials of vegetarian diets. J Acad
Nutr Diet. 2015;115(6):954–69.
37. Kim SH, Yi SW, Yi JJ, Kim YM, Won YJ. Association between body mass
index and the risk of hip fracture by sex and age: a prospective cohort
study. J Bone Miner Res. 2018;33(9):1603–11.
38. Gonnelli S, Caffarelli C, Nuti R. Obesity and fracture risk. Clin Cases Miner
Bone Metab. 2014;11(1):9–14.
39. Hayes WC, Myers ER, Morris JN, Gerhart TN, Yett HS, Lipsitz LA. Impact
near the hip dominates fracture risk in elderly nursing home residents
who fall. Calcif Tissue Int. 1993;52(3):192–8.
40. Kim KH, Lee JH, Lim EJ. Weak psoas and spine extensors potentially
predispose to hip fracture. Hip Int. 2021;31(3):430–4.
41. Wu AM, Sun XL, Lv QB, Zhou Y, Xia DD, Xu HZ, et al. The relationship
between dietary protein consumption and risk of fracture: a subgroup
and dose-response meta-analysis of prospective cohort studies. Sci Rep.
2015;5:8.
42. Bailey RL, van Wijngaarden JP. The role of B-vitamins in bone health and
disease in older adults. Curr. 2015;13(4):256–61.
43. British Nutrition Foundation. Nutrition requirements. 2021. [Available
from: https://​www.​nutri​tion.​org.​uk/​media/​nmmew​dug/​nutri​tion-​requi​
remen​ts.​pdf ].
44. Yao P, Bennett D, Mafham M, Lin X, Chen Z, Armitage J, et al. Vitamin D
and calcium for the prevention of fracture: a systematic review and meta-
analysis. JAMA Netw Open. 2019;2(12):e1917789.
45. Allen NE, Appleby PN, Davey GK, Kaaks R, Rinaldi S, Key TJ. The associa-
tions of diet with serum insulin-like growth factor I and its main binding
proteins in 292 women meat-eaters, vegetarians, and vegans. Cancer
Epidemiol Biomark Prev. 2002;11(11):1441–8.
46. Yuan S, Wan ZH, Cheng SL, Michaëlsson K, Larsson SC. Insulin-like growth
factor-1, bone mineral density, and fracture: a Mendelian randomization
study. J Clin Endocrinol Metab. 2021;106(4):e1552–e8.
47. Swift CG. Prevention and management of hip fracture in older patients.
Practitioner. 2011;255(1743):29–33, 3.
48. Robinson CM, Court-Brown CM, McQueen MM, Christie J. Hip fractures
in adults younger than 50 years of age. Epidemiology and results. Clin
Orthop Relat Res. 1995;312:238–46.
49. Curtain F, Grafenauer S. Plant-based meat substitutes in the flexitar-
ian age: an audit of products on supermarket shelves. Nutrients.
2019;11(11):2603.
50. Barrett-Connor E, Siris ES, Wehren LE, Miller PD, Abbott TA, Berger ML,
et al. Osteoporosis and fracture risk in women of different ethnic groups.
J Bone Miner Res. 2005;20(2):185–94.

Publisher’s Note Ready to submit your research ? Choose BMC and benefit from:
Springer Nature remains neutral with regard to jurisdictional claims in pub-
lished maps and institutional affiliations. • fast, convenient online submission
• thorough peer review by experienced researchers in your field
• rapid publication on acceptance
• support for research data, including large and complex data types
• gold Open Access which fosters wider collaboration and increased citations
• maximum visibility for your research: over 100M website views per year

At BMC, research is always in progress.

Learn more biomedcentral.com/submissions