Long-term effects of a very-low-carbohydrate weight-loss diet and an isocaloric low-fat diet on bone health in obese adults

Grant D. Brinkworth, Thomas P. Wycherley, Manny Noakes, Jonathan D. Buckley, Peter M. Clifton

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Objective Compromised bone health is a frequently cited concern of very-low-carbohydrate (LC) diets, although limited data are available from long-term, well-controlled, randomized studies. This study compared the effects of an energy-restricted LC diet and traditional, higher-carbohydrate, low-fat (LF) diet on bone health after 12 mo. Methods One hundred eighteen abdominally obese adults were randomized to consume either an energy-restricted (∼6–7 MJ/d [∼1450–1650 kcal/d]), planned isocaloric LC, or LF diet for 12 mo. Body weight, total body bone mineral content and bone mineral density (BMD), and serum bone crosslaps were assessed pre- and postintervention. Results Sixty-five participants completed the study (LC = 32, LF = 33; age: 51.3 ± 7.1 y; BMI: 33.4 ± 4.0 kg/m2). Weight loss was similar in both groups (LC: −14.5 ± 9.8 kg, LF: −11.7 ± 7.3 kg; P = 0.26). By 1 y, total body bone mineral content had not changed in either group (LC: 2.84 ± 0.47 to 2.88 ± 0.49 kg, LF: 3.00 ± 0.52 to 3.00 ± 0.51 kg; P = 0.07 time × diet effect). In both groups, total body BMD decreased (LC: 1.26 ± 0.10 to 1.22 ± 0.09 g/cm2, LF: 1.26 ± 0.09 to 1.23 ± 0.08 g/m2; P < 0.001 time) and bone serum crosslaps increased (LC: 319.3 ± 142.6 to 396.5 ± 172.0 ng/L, LF: 276.3 ± 100.6 to 365.9 ± 154.2 ng/L; P < 0.001 time) independent of diet composition (P ≥ 0.25 time × diet effect). Future studies would be strengthened by the assessment of regional BMD at clinically relevant sites (i.e., hip and spine) and multiple markers of bone turnover. Conclusions Weight loss following a hypocaloric LC diet compared with an LF diet does not differentially affect markers of bone health over 12 mo in overweight and obese adults.

Original languageEnglish
Pages (from-to)1033-1036
Number of pages4
JournalNutrition
Volume32
Issue number9
DOIs
Publication statusPublished - 1 Sep 2016

Keywords

  • Bone
  • Diet
  • Macronutrient composition
  • Obesity
  • Weight loss

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Nutrition and Dietetics

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