Vitamin B12 insufficiency and deficiency: a review of nondisease risk factors.

Vitamin B12 deficiency and insufficiency can lead to both hematological and neurological impairments. This review examines nondisease causes and risk factors associated with dietary availability, such as eating habits, food processing, cooking techniques, and bioavailability, as well as increased physiological needs and iatrogenic factors linked to medication use or surgical procedures. As a result of these nondisease influences, groups at higher risk include vegans, vegetarians, older adults, individuals with limited diets, breastfed and preterm infants, and those who primarily consume foods prepared or cooked in ways that reduce vitamin B12 content, as well as individuals on certain medications or who have undergone specific surgeries. Recognizing these diverse risk factors helps develop strategies for prevention and intervention to minimize the adverse health effects related to B12 deficiency and insufficiency.

Plant-based dietary pattern and low muscle mass: a nation-wide cohort analysis of Chinese older adults.

BACKGROUND: It remains unclear whether plant-based or animal-based dietary patterns are more beneficial for older adults more in maintaining muscle mass. Using a prospective cohort with nationwide sample of China older adults in this study, we aimed to examine the relationship between adhering to plant-based diet patterns or animal-based diet patterns and muscle loss. METHODS: We included 2771 older adults (≥ 65 years) from the Chinese Longitudinal Health Longevity Survey (CLHLS) with normal muscle mass at baseline (2011 and 2014 waves), which followed up into 2018. Plant-based dietary pattern scores and preference subgroups were constructed using 16 common animal-based and plant-based food frequencies. We used the corrected appendicular skeletal muscle mass (ASM) prediction formula to assess muscle mass. We applied the Cox proportional hazard risk regression to explore associations between dietary patterns and low muscle mass (LMM). RESULTS: During a mean of 4.1 years follow-up, 234 (8.4%) participants with normal muscle mass at baseline showed LMM. The plant-based dietary pattern reduced the risk of LMM by 5% (Hazard Ratios [HR]: 0.95, 95% confidence intervals [95%CI]: 0.92-0.97). In addition, a high plant-based food company with a high animal-based food intake pattern reduced the risk of LMM by 60% (HR: 0.40, 95% CI: 0.240-0.661) and 73% (HR: 0.27, 95% CI: 0.11-0.61) in the BADL disability and IADL disability population compared with a low plant-based food and high animal-based food intake, whereas a high plant-based food and low animal-based food intake was more beneficial in reducing the risk of LMM in the normal BADL functioning (HR: 0.57, 95% CI: 0.35-0.90) and IADL functioning (HR: 0.51, 95% CI: 0.28-0.91) population. CONCLUSIONS: When it comes to maintaining muscle mass in older Chinese people with functional independence, a plant-based diet pattern is more beneficial and effective than the animal-based one. People with functional dependence may profit from a combination of plant-based and animal-based diets to minimize muscle loss.

Association between vegetarian diet and gouty arthritis: A retrospective cohort study.

BACKGROUND AND AIMS: A vegetarian diet is rich in vegetables, fruits, and soy products. Although vegetarian diet is beneficial for improving the health outcomes such as body mass index, metabolic syndrome, cardiovascular disease, and mortality rate, the association between a vegetarian diet and gout incidence is not well known. METHODS AND RESULTS: We linked the MJ Health Survey Data and MJ Biodata 2000 with the National Health Insurance Research Database (NHIRD) and the National Registration of Death (2000-2018). Information on the diet was collected from the MJ Health Survey Data, and the incidence of gouty arthritis was confirmed using the NHIRD. The Kaplan-Meier survival curve and log-rank test were used to compare the differences between vegetarian and non-vegetarian participants. Cox regression models were used to estimate the risk of the incidence of gouty arthritis. Among 76,972 participants, 37,297 (48.46%) were men, 2488 (3.23%) were vegetarians and the mean age was 41.65 ± 14.13 years. The mean baseline uric acid level was 6.14 ± 1.65 mg/dL. A total of 16,897 participants developed gouty arthritis, including 16,447 (22.08%) non-vegetarians and 450 (18.9%) vegetarians over a mean follow-up of 19 years. Significant differences were observed in the Kaplan-Meier survival curves between vegetarians and non-vegetarians (log-rank p < 0.001). Vegetarians had a significantly decreased incidence of gouty arthritis compared with non-vegetarians (hazard ratio = 0.87, 95% confidence interval = 0.78-0.98, p = 0.02) after adjusting for potential confounders. CONCLUSION: People with a vegetarian diet had a significantly decreased risk of developing gouty arthritis compared with non-vegetarians in Taiwan.

Risk of hip fracture in meat-eaters, pescatarians, and vegetarians: a prospective cohort study of 413,914 UK Biobank participants.

BACKGROUND: Meat-free diets may be associated with a higher risk of hip fracture, but prospective evidence is limited. We aimed to investigate the risk of hip fracture in occasional meat-eaters, pescatarians, and vegetarians compared to regular meat-eaters in the UK Biobank, and to explore the role of potential mediators of any observed risk differences. METHODS: Middle-aged UK adults were classified as regular meat-eaters (n = 258,765), occasional meat-eaters (n = 137,954), pescatarians (n = 9557), or vegetarians (n = 7638) based on dietary and lifestyle information at recruitment (2006-2010). Incident hip fractures were identified by record linkage to Hospital Episode Statistics up to September 2021. Multivariable Cox regression models were used to estimate associations between each diet group and hip fracture risk, with regular meat-eaters as the reference group, over a median follow-up time of 12.5 years. RESULTS: Among 413,914 women, 3503 hip fractures were observed. After adjustment for confounders, vegetarians (HR (95% CI): 1.50 (1.18, 1.91)) but not occasional meat-eaters (0.99 (0.93, 1.07)) or pescatarians (1.08 (0.86, 1.35)) had a greater risk of hip fracture than regular meat-eaters. This is equivalent to an adjusted absolute risk difference of 3.2 (1.2, 5.8) more hip fractures per 1000 people over 10 years in vegetarians. There was limited evidence of effect modification by BMI on hip fracture risk across diet groups (pinteraction = 0.08), and no clear evidence of effect modification by age or sex (pinteraction = 0.9 and 0.3, respectively). Mediation analyses suggest that BMI explained 28% of the observed risk difference between vegetarians and regular meat-eaters (95% CI: 1.1%, 69.8%). DISCUSSION: Vegetarian men and women had a higher risk of hip fracture than regular meat-eaters, and this was partly explained by their lower BMI. Ensuring adequate nutrient intake and weight management are therefore particularly important in vegetarians in the context of hip fracture prevention. TRIAL REGISTRATION: NCT05554549, registered retrospectively.

The relationship between a plant-based diet and mental health: Evidence from a cross-sectional multicentric community trial (LIPOKAP study).

BACKGROUND: Dietary patterns emphasizing plant foods might be neuroprotective and exert health benefits on mental health. However, there is a paucity of evidence on the association between a plant-based dietary index and mental health measures. OBJECTIVE: This study sought to examine the association between plant-based dietary indices, depression and anxiety in a large multicentric sample of Iranian adults. METHODS: This cross-sectional study was performed in a sample of 2,033 participants. A validated food frequency questionnaire was used to evaluate dietary intakes of participants. Three versions of PDI including an overall PDI, a healthy PDI (hPDI), and an unhealthy PDI (uPDI) were created. The presence of anxiety and depression was examined via a validated Iranian version of the Hospital Anxiety and Depression Scale (HADS). RESULTS: PDI and hPDI were not associated to depression and anxiety after adjustment for potential covariates (age, sex, energy, marital status, physical activity level and smoking). However, in the crude model, the highest consumption of uPDI approximately doubled the risk of depression (OR= 2.07, 95% CI: 1.49, 2.87; P<0.0001) and increased the risk of anxiety by almost 50% (OR= 1.56, 95% CI: 1.14, 2.14; P= 0.001). Adjustment for potential confounders just slightly changed the associations (OR for depression in the fourth quartile= 1.96; 95% CI: 1.34, 2.85, and OR for anxiety in the fourth quartile= 1.53; 95% CI: 1.07, 2.19). CONCLUSIONS: An unhealthy plant-based dietary index is associated with a higher risk of depression and anxiety, while plant-based dietary index and healthy plant-based dietary index were not associated to depression and anxiety.

A comprehensive review of healthy effects of vegetarian diets.

AIMS: A comprehensive review comparing the effect of vegetarian (V) and non-vegetarian (NV) diets on the major cardiometabolic diseases' outcomes was performed. DATA SYNTHESIS: We performed literature research (up to December 31, 2022) of the evidence separately for vascular disease (VD), obesity (OB), dyslipidemia (Dysl), hypertension (HPT), type 2 diabetes (T2D), metabolic syndrome (MetS), analyzing only cohort studies and randomized controlled studies (RCTs) and comparing the effect of V and NV diets. Cohort studies showed advantages of V diets compared to NV diets on incidence and/or mortality risk for ischemic heart disease, overweight and OB risk. Most cohort studies showed V had lower risk of HPT and lower blood pressure (BP) than NV and V diets had positive effects on T2D risk or plasma parameters. The few cohort studies on the risk of MetS reported mixed results. In RCTs, V diets, mainly low-fat-vegan ones, led to greater weight loss and improved glycemic control than NV diets and in the only one RCT a partial regression of coronary atherosclerosis. In most RCTs, V diets significantly reduced LDL-C levels (but also decreased HDL-C levels) and BP. CONCLUSIONS: In this comprehensive review of the association between V diets and cardiometabolic outcomes, we found that following this type of diet may help to prevent most of these diseases. However, the non-uniformity of the studies, due to ethnic, cultural, and methodological differences, does not allow for generalizing the present results and drawing definitive conclusions. Further, well-designed studies are warranted to confirm the consistency of our conclusions.

The Hidden Dangers of Plant-Based Diets Affecting Bone Health: A Cross-Sectional Study with U.S. National Health and Nutrition Examination Survey (NHANES) Data from 2005-2018.

The plant-based dietary pattern has been recommended for its potential health and environmental benefits, but its association with bone loss needs to be further explored. This study aimed to investigate the association between three plant-based diet indexes and bone loss in 16,085 adults, using data from the National Health and Nutrition Examination Survey. Three plant-based diet indexes (PDI, hPDI, and uPDI) were calculated from two NHANES 24-h dietary recall interviews, to characterize a plant-based diet. A multinomial logistic regression model was used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI). Higher hPDI and PDI were associated with increased risk of bone loss (ORQ5 vs. Q1 = 1.50; 95% CI: 1.24-1.81 for hPDI; ORQ5 vs. Q1 = 1.22; 95% CI: 1.03-1.45 for PDI), while higher uPDI was associated with increased risk of osteoporosis (ORQ5 vs. Q1 = 1.48; 95% CI: 1.04-2.11). A harmful association between plant-based diet indexes (hPDI and PDI) and osteopenia was observed at the lumbar spine rather than the femoral neck. We conducted several sensitivity analyses to ensure the robustness of results, including subgroup analysis, exclusion of people taking anti-osteoporotic and estrogenic drugs, further adjustment for menopausal status, corticosteroid usage, and dietary supplements, and calculation of E-value. Our study demonstrates the deleterious effects of a plant-based diet on bone health and emphasizes the importance of a balanced diet.

Dietary Habits and Lifestyle, Including Cardiovascular Risk among Vegetarians and Omnivores during the COVID-19 Pandemic in the Polish Population.

Background: This study assessed how two food groups­omnivores (OMN) and vegetarians (VEGE)­differ in lifestyle changes, including dietary habits during the COVID-19 pandemic. Materials: A total of 861 persons participated in the survey and were divided into two groups: persons following a mixed diet (n = 489) and vegetarians, including vegans (n = 372). The mean age shows no significant differences. Methods: An online survey was conducted on the Polish population during the COVID-19 pandemic. Data was collected using social media; the survey was intended for adults and included separate sheets for different diets (OMN vs. VEGE). Results: The results in both groups were similar regarding the burden of premature diseases. Most respondents (~90%) did not indicate cardiovascular disease abnormalities. In the OMN group, overweight and obesity occurred more often, and the OMN group also showed a higher percentage of people reporting weight gain (OMN 42.7% vs. VEGE 35.9%). The results disclosed the VEGE group significantly more frequently chose products, i.e., vegetables (p = 0.029), legumes (p < 0.001), and dairy products or their plant substitutes (p = 0.002), compared to the OMN group. Conclusions: The VEGE group revealed the most regularities in dietary habits during the pandemic.

The importance of vitamin B12 for individuals choosing plant-based diets.

Vitamin B12 is an essential nutrient that is not made by plants; consequently, unfortified plant-based foods are not a reliable supply. Recent estimates suggest high rates of vitamin B12 deficiency among the vegetarian and vegan populations, particularly in pregnant women or women of child-bearing age who, for ethical and health reasons, are shifting towards higher consumption of plant-based foods in ever-increasing numbers. Vitamin B12 plays crucial metabolic roles across the life-course and in particular during pregnancy and in early development (first 1000 days of life). Evidence now implicates vitamin B12 deficiency with increased risk to a range of neuro, vascular, immune, and inflammatory disorders. However, the current UK recommended nutrient intake for vitamin B12 does not adequately consider the vitamin B12 deficit for those choosing a plant-based diet, including vegetarianism and in particular veganism, representing a hidden hunger. We provide a cautionary note on the importance of preventing vitamin B12 deficits for those individuals choosing a plant-based diet and the health professionals advising them.

Plant-Based Dietary Patterns versus Meat Consumption and Prevalence of Impaired Glucose Intolerance and Diabetes Mellitus: A Cross-Sectional Study in Australian Women.

This study aimed to compare the prevalence of impaired glucose tolerance (IGT) and diabetes mellitus (DM) among Australian women following plant-based diets (PBD) compared to regular meat eaters. A cross sectional analysis of the mid-aged cohort (1946−1951) of the Australian Longitudinal Study on Women's Health was conducted on completers of Survey 7 in 2013 with complete FFQ data available (n = 9102). Dietary patterns were categorized as PBD (vegan, lacto-ovo vegetarian, pesco-vegetarian, semi-vegetarian) and regular meat eaters. Meat eaters were further categorized into high and low consumption and outcomes included self-reported prevalence of IGT and DM. Participants were identified as regular meat eaters (n = 8937) and PBD (n = 175). Prevalence of IGT was lower in PBD (0−1.2%) compared to regular meat eaters (9.1%). Consolidation of PBD to a single group (vegetarians) indicated a lower prevalence of DM in vegetarians compared to regular meat eaters (3.9% vs. 9.1%). Women consuming meat daily/multiple times per day had significantly higher odds of IGT (OR 1.5, 95%CI 1.1 to 2.1, p = 0.02). Individuals consuming processed meat daily/multiple times per day had significantly higher odds of DM compared to those consuming less than daily (Odds ratio (OR) 1.7, 95% confidence interval (CI) 1.3 to 2.3, p < 0.0001). After adjustment for covariates, statistical significance was lost largely due to the addition of BMI to the model. Prevalence of IGT and DM were lower in women following PBD and higher in high consumers of meat and processed meat. The relationship between meat consumption and IGT/diabetes status appears to be mediated, at least in part, by an increase in body mass index (BMI). Future studies are warranted to investigate the mechanisms and other lifestyle factors underpinning the association between high meat consumption and increased risk of IGT and DM.

Risk of hip fracture in meat-eaters, pescatarians, and vegetarians: results from the UK Women's Cohort Study.

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 pescatarians (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: ClinicalTrials.gov , NCT05081466.

Association between vegetarian and vegan diets and depression: A systematic review.

Recent evidence suggests that vegetarian and vegan diets may increase the risk and symptoms of depression, a mental health condition affecting 350 million people globally. We aimed to systematically review the literature on the associations between vegetarian and/or vegan diets and the risk or symptoms of depression using evidence from both observational and intervention studies. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with pre-specification of all methods. A systematic search for relevant papers was performed on Medline and Embase, Web of Science and the Cochrane Library for cohort, case-control, cross-sectional studies or randomised controlled trials examining associations between a vegetarian or vegan diet and depression in adults. Three independent reviewers extracted data and assessed risk of bias using the National Heart, Lung, and Blood Institute of the National Institutes of Health for Quality Assessment of Observational Cohort and Cross-Sectional Studies and Controlled Studies. Evidence was tabulated according to the type of diet analysed as vegetarian, vegan or both and narratively synthesised. A total of 23 studies (18 cross-sectional, three prospective cohort and two randomised controlled trials) with 25 study outcomes were eligible for inclusion in this review. Conflicting evidence was found on the association between vegetarian or vegan diets and depression. Eleven (44%) of the outcomes indicated that vegetarian and vegan diets were associated with higher rates of depression, while seven (28%) outcomes revealed beneficial effects of the diets on depression. Seven (28%) outcomes found no association between vegetarian and vegan diets and depression, although two of these studies found a higher risk of depression in some groups. The quality of evidence was rated as good for four of the studies with the remaining 19 studies rated as fair. The evidence on the effect of vegetarian and vegan diets on depression is contradictory, possibly due to the heterogeneity of the studies analysed. Further research, including longitudinal and intervention studies, is required to resolve this observation.

Is vegetarianism related to anxiety and depression? A cross-sectional survey in a French sample.

OBJECTIVE: The relationship between vegetarianism and mental health is controversial. The aim of the present study is to examine the cross-sectional association between anxiety, depression, and vegetarianism in a French sample while controlling for potential confounders. DESIGN: Self-reported questionnaire data were obtained from a large cross-sectional sample. PARTICIPANTS AND SETTING: We included an online sample of 6578 participants aged 18-90, 70.8% females. RESULTS: Analyses of variance with age, gender, body mass index (BMI), educational level, monthly income, and city size as covariates showed that vegetarians and non-vegetarians did not appear to have significantly different levels of anxiety or depression. CONCLUSION: Our findings do not suggest a link between plant-based diet and anxiety or depression, either before or after adjustment for relevant factors.

Effect of vegetarian diets on renal function in patients with chronic kidney disease under non-dialysis treatment: A scoping review.

Vegetable protein diets (VPDs) in chronic kidney disease (CKD) patients may be related to beneficial biological actions and possibly clinical impact. This is a scoping review that merge studies that evaluated the effect of a vegetarian diet on kidney function in adults with CKD under non-dialysis treatment. The evaluated outcome was the impact in renal function assessed by eGFR or creatinine clearance. MEDLINE (accessed by PubMed) was searched up to September 8, 2020. Data were extracted by two independent reviewers, who also assessed the quality of the studies. Of 341 retrieved articles, 4 studies assessing 324 patients were included in the analysis. One study showed that a very low-protein ketoanalogue-supplemented vegetarian diet had benefits in relation to a conventional low-protein diet, while the other three studies demonstrated no difference in kidney function between the evaluated diets. Additional studies are needed to assess the benefits of vegetarian diets for further recommendations in CKD management.

Vegetarians, Pescatarians and Flexitarians with Adequate Vitamin B12 Levels Have No Increased Risk of Polyneuropathy.

BACKGROUND: In recent years, an increasing number of people adapt to a vegetarian, pescatarian or flexitarian dietary pattern that reduces the consumption of meat and fish. Although these dietary patterns have a risk for developing vitamin B12 deficiency associated polyneuropathy, it is unknown whether this risk is still increased when vitamin B12 levels are adequate. OBJECTIVE: To examine whether a vegetarian, pescatarian or flexitarian dietary pattern is associated with an increased risk for idiopathic axonal polyneuropathy. METHODS: We conducted a case-control study that included 256 idiopathic axonal polyneuropathy patients with adequate vitamin B12 blood levels and 630 controls. We used questionnaire data to determine the frequency of meat and fish consumption and defined dietary patterns. RESULTS: The vegetarian (no meat or fish consumption) and the pescatarian (fish consumption, no meat consumption) dietary patterns showed no increased risk of axonal polyneuropathy. Frequency-effect analysis and quantity-effect analysis also did not show that a reduction of meat or fish consumption (flexitarian dietary pattern), either small or large, changed the risk of axonal polyneuropathy. CONCLUSIONS: We did not find an increased risk for axonal polyneuropathy among people with a vegetarian, pescatarian or flexitarian diet and an adequate vitamin B12 level.

A Fermented Milk Product Containing B. lactis CNCM I-2494 Improves the Tolerance of a Plant-Based Diet in Patients with Disorders of Gut-Brain Interactions.

Healthy, plant-based diets, rich in fermentable residues, may induce gas-related symptoms. The aim of this exploratory study was to assess the effects of a fermented milk product, containing probiotics, on the tolerance of a healthy diet in patients with disorders of gut-brain interactions (DGBI), complaining of excessive flatulence. In an open design, a 3-day healthy, mostly plant-based diet was administered to patients with DGBI (52 included, 43 completed) before and at the end of 28 days of consumption of a fermented milk product (FMP) containing Bifidobacterium animalis subsp. lactis CNCM I-2494 and lactic acid bacteria. As compared to a habitual diet, the flatulogenic diet increased the perception of digestive symptoms (flatulence score 7.1 ± 1.6 vs. 5.8 ± 1.9; p < 0.05) and the daily number of anal gas evacuations (22.4 ± 12.5 vs. 16.5 ± 10.2; p < 0.0001). FMP consumption reduced the flatulence sensation score (by -1.6 ± 2.2; p < 0.05) and the daily number of anal gas evacuations (by -5.3 ± 8.2; p < 0.0001). FMP consumption did not significantly alter the overall gut microbiota composition, but some changes in the microbiota correlated with the observed clinical improvement. The consumption of a product containing B. lactis CNCM I-2494 improved the tolerance of a healthy diet in patients with DGBI, and this effect may be mediated, in part, by the metabolic activity of the microbiota.

Association between Unhealthful Plant-Based Diets and Possible Risk of Dyslipidemia.

The relationship between the various types of diets derived from plants and vulnerability of dyslipidemia has rarely been investigated, and limited data exist in Asians whose dietary pattern is fairly different from that of the Western population. We aim to analyze the relationship between three plant-based diet indices (PDI) and the risk of dyslipidemia. Participants included 173,209 Korean adults who were aged ≥40 years from the Korean Genome and Epidemiology Study_Health Examination (2004-2013). A food frequency questionnaire (FFQ) was used to assess dietary intake. Three PDI were quantified for the study: overall PDI, healthful PDI (hPDI), and unhealthful PDI (uPDI). Among the 147,945 included, 48,166 (32.6%) of participants had dyslipidemia. Great adherence to uPDI was related with 15% greater odds of having dyslipidemia (OR: 1.15; 95% CI: 1.11-1.20, p-trend < 0.0001). No significant association was observed between PDI, hPDI, and dyslipidemia. The association between uPDI and dyslipidemia was significantly stronger among participants aged ≥55 years when compared to participants aged <55 years (p-value for interaction = 0.001). The quality of plant foods is vital in preventing dyslipidemia among people consuming high plant-based food diets.

The impact of plant-based diets on female bone mineral density: Evidence based on seventeen studies.

BACKGROUND: An increase in awareness of plant-based diets has brought forth numerous studies on bone mineral density (BMD). The present systematic review and meta-analysis was designed to compare the effect between plant-based diets and omnivores on female BMD. METHODS: We searched the Cochrane Library, PubMed, EMBASE, and Web of Science and up to July 1, 2020. Mean difference (MD) with its 95% confidence interval (CI) was estimated to compare the outcomes of the groups. We compared BMD at the lumbar spine, femoral neck and whole body respectively between plant-based diets and omnivores. In addition, we performed subgroup analyses according to different clinical characteristics for further exploration. Two reviewers assessed trial quality and extracted data independently. All statistical analyses were performed using standard statistical procedures provided in Review Manager 5.2. RESULTS: A total of 17 cross-sectional studies including 13,888 patients were identified for the present meta-analysis. Our pooled result indicated that population with plant-based diets had lower BMD than omnivores at the lumbar spine (MD -0.03; 95% CI -0.04 to -0.02; P < .0001), femoral neck (MD -0.04; 95% CI -0.05 to -0.03; P < .00001) and whole body (MD -0.04; 95% CI -0.06 to -0.01; P = .01), respectively. Further exploration indicated that especially females with plant-based diets experienced significantly lower BMD at lumbar spine (MD -0.03; 95% CI -0.04 to -0.02; 3173 pts), femoral neck (MD -0.04; 95% CI -0.05 to -0.03; 10,656 pts) and whole body (MD -0.05; 95% CI -0.10 to -0.00; P = .04). In addition, we performed subgroup analyses and found lower BMD at lumbar spine and femoral neck in both vegetarians and vegans. CONCLUSIONS: The present meta-analysis indicated that plant-based diets may be correlated with lower BMD of women when compared with omnivore population. However, this does not diminish the fact that a plant-based diet can be a harmful option to the overall bone health of population and more prospective researches are needed to clear the impact of plant-based diets on bone health.

Diet-Related Phototoxic Reactions in Psoriatic Patients Undergoing Phototherapy: Results from a Multicenter Prospective Study.

Vegans and vegetarians often consume foods containing photosensitizers capable of triggering phytophotodermatitis. The potential effect of vegan and vegetarian diets on the response of psoriatic patients undergoing phototherapy is not well characterized. We assessed clinical outcomes of vegan, vegetarian and omnivore adult psoriatic patients undergoing band ultraviolet B phototherapy (NB-UVB). In this multicenter prospective observational study, we enrolled 119 adult, psoriatic patients, of whom 40 were omnivores, 41 were vegetarians and 38 were vegans, with phototherapy indication. After determining the minimum erythemal dose (MED), we performed NB-UVB sessions for 8 weeks. The first irradiation dosage was 70.00% of the MED, then increased by 20.00% (no erythema) or by 10.00% (presence of erythema) until a maximum single dose of 3 J/cm2 was reached and constantly maintained. All the enrolled patients completed the 8 weeks of therapy. Severe erythema was present in 16 (42.11%) vegans, 7 (17.07%) vegetarians and 4 (10.00%) omnivores (p < 0.01). MED was lowest among vegans (21.18 ± 4.85 J/m2), followed by vegetarians (28.90 ± 6.66 J/m2) and omnivores (33.63 ± 4.53 J/m2, p < 0.01). Patients with severe erythema were more likely to have a high furocumarin intake (OR 5.67, 95% CI 3.74-8.61, p < 0.01). Vegans consumed the highest amount of furocumarin-rich foods. A model examining erythema, adjusted for gender, age, skin type, MED, phototherapy type, number of phototherapies and furocumarin intake, confirmed that vegans had a lower number of treatments. Vegans had more frequent severe erythema from NB-UVB, even after adjustment of the phototherapy protocol for their lower MED. Assessing diet information and adapting the protocol for vegan patients may be prudent.