Veganism, vegetarianism, bone mineral density, and fracture risk: a systematic review and meta-analysis

Abstract

The numbers of vegans and vegetarians have increased in the last decades. However, the impact of these diets on bone health is still under debate. Objective: This systematic review and meta-analysis sought to study the impact of vegetarian and vegan diets on bone mineral density (BMD) and fracture risk. Data Sources: A systematic search was conducted of PubMed, Scopus, and Science Direct, covering the period from the respective start date of each database to November 2017. Data Extraction: Two investigators evaluated 275 studies against the inclusion criteria (original studies in humans, written in English or Spanish and including vegetarian or vegan diets and omnivorous diets as factors with BMD values for the whole body, lumbar spine, or femoral neck and/or the number of fractures as the outcome) and exclusion criteria (articles that did not include imaging or studies that included participants who had suffered a fracture before starting the vegetarian or vegan diet). The quality assessment tool for observational cohort and cross-sectional studies was used to assess the quality of the studies. Results: Twenty studies including 37 134 participants met the inclusion criteria. Compared with omnivores, vegetarians and vegans had lower BMD at the femoral neck and lumbar spine and vegans also had higher fracture rates. Conclusions: Vegetarian and vegan diets should be planned to avoid negative consequences on bone health. Systematic Review Registration: PROSPERO registration no. CRD42017055508.

Brazilian vegetarians diet quality markers and comparison with the general population: A nationwide cross-sectional study

“…It is possible to suggest that the diet of most participants was based on cereals, legumes, fruits, and vegetables, which is in line with the main recommendations from the Dietary Guidelines for the Brazilian Population [61]. A recent systematic review published in 2019 evaluating the nutritional quality of vegetarian diets showed that vegetarians have a higher intake of fruits, whole grains, green vegetables, and legumes [62].…”

“…Nutritional quality was measured with different diet quality indexes. Even though each index evaluates different items of the diet, the quality of the diet is always based on a combination of adequate components, such as fruits and vegetables, and moderation components, such as refined sugar [62].…”

Meat and mental health: a systematic review of meat abstention and depression, anxiety, and related phenomena

“…Moreover, and in contrast to the positive associations between health and vegetarianism Dinu et al 2017;Singh, Sabat e, and Fraser 2003;Viguiliouk et al 2019), recent results suggest that individuals who abstain from meat and/or other animal-based foods may suffer from nutritional deficiencies (e.g., vitamins B 12 and D, x-3 fatty acids, calcium, iron, and zinc; Craig 2010; Dwyer 1991) with concomitant poorer physical health (Appleby et al 2007;Burkert et al 2014b;Cofnas 2019;Iguacel et al 2019). Furthermore, there is an emerging body of evidence that meat-abstention is linked to mental disorders (Perica and Dela s 2011;Young and Conquer 2005) and poorer psychological well-being (Baines, Powers, and Brown 2007;Hibbeln et al 2018;Matta et al 2018;Michalak, Zhang, and Jacobi 2012;Nezlek, Forestell, and Newman 2018;Rosenfeld 2018).…”

Impact of whole dairy matrix on musculoskeletal health and aging–current knowledge and research gaps

“…A recent meta-analysis of observational studies of vegan/ vegetarian diets on bone health reported that a diet free of dairy products was associated with lower BMD at the femoral neck and lumbar spine and higher incidence of fractures in adults [71]. Two case-control studies including infants (10-20 months old), children, adolescents, and young adults (up to 20 years) found impaired bone strength and higher fracture risk among those not consuming dairy products [72,73].…”