Dietary patterns and hip fracture in the Adventist Health Study 2: combined vitamin D and calcium supplementation mitigate increased hip fracture risk among vegans

• Published in: The American journal of clinical nutrition Vol. 114; no. 2; pp. 488 - 495
• Main Authors: Thorpe, Donna L, Beeson, W Lawrence, Knutsen, Raymond, Fraser, Gary E, Knutsen, Synnove F
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2021; Oxford University Press; American Society for Clinical Nutrition, Inc
• Subjects: Adequacy; Adventist Health Study; Aged; Calciferol; Calcium; Calcium - administration & dosage; Diet; Diet - adverse effects; diet pattern; dietary nutrients; Dietary Supplements; Female; Females; Fractures; Hip; hip fracture; Hip Fractures - prevention & control; Humans; Male; Men; Middle Aged; Original Research Communications; Post-menopause; Risk; Risk Factors; Vegan; Veganism; Vegans; Vegetarian diet; Vegetarianism; Vitamin D; Vitamin D - administration & dosage; LOV; AHS-2; hip fracture; diet pattern; BMD; dietary nutrients; Adventist Health Study; vegan; HT; NVEG; PYRS
• ISSN: 0002-9165; 1938-3207; 1938-3207
• DOI: 10.1093/ajcn/nqab095

Concerns regarding the adequacy of vegetarian diets with respect to fracture risk continue. We aimed to explore the influence of 5 previously defined dietary patterns on hip fracture risk and whether this association is modified by concomitant calcium and vitamin D supplementation. The Adventist Health Study 2 is a prospective cohort study in which participants were enrolled during 2002–2007; proportional hazards regression analyses were used to estimate fracture risk. Participants reside throughout the United States and Canada. A total of 34,542 non-Hispanic white peri- and postmenopausal women and men 45 y and older responded to the biennial hospital history form and were followed for a median of 8.4 y. The study identified 679 incident hip fractures during 249,186 person-years of follow-up. Fracture risk varied according to dietary pattern, with a clear effect modification by concurrent supplementation with both vitamin D and calcium. In multivariable models, including adjustment for calcium and vitamin D supplementation, female vegans had 55% higher risk of hip fracture (HR: 1.55; 95% CI: 1.06, 2.26) than nonvegetarians (NVEGs), whereas there was no association between diet pattern and hip fracture risk in men. When further stratifying females on supplement use with both vitamin D and calcium, vegans taking both supplements were at no greater risk of hip fracture than the subjects with other dietary patterns including the NVEGs. Without combined supplementation of both vitamin D and calcium, female vegans are at high risk of hip fracture. However, with supplementation the excessive risk associated with vegans disappeared. Further research is needed to confirm the adequacy of a vegan diet supplemented with calcium and vitamin D with respect to risk of fracture. Vegans are at increased for hip fractures: Combined supplementation of vitamin D and calcium may rescue this.