Efficacy and tolerability of calcium, vitamin D and a plant-based omega-3 oil for osteopenia: A pilot RCT

ObjectivesOur pilot study tested the efficacy, acceptability and tolerability of DHA supplementation in addition to calcium and vitamin D in individuals with osteopenia.Study design40 participants were randomised to either algal oil containing 400 mg docosahexanoic acid (DHA) daily or placebo. All participants received 1200 mg calcium carbonate with vitamin D3 1000 IU daily.Main outcome measuresBone mineral density (BMD) was measured at baseline and 12 months. Bone turnover was assessed with serum c-terminal telopeptides (CTx) at baseline and 12 months. Tolerability and acceptability were assessed using a validated questionnaire.ResultsMean CTx was suppressed after 12 months for all participants (p = 0.04) with no difference in effect size between DHA and control groups (p = 0.53). Changes in CTx at 12 months were significantly correlated with changes in BMD at the lumbar spine (p = 0.01) and total proximal femur (TPF) (p = 0.03). There was a non-significant trend towards rising BMD at 12 months. Participants rated the supplements as tolerable and acceptable, with few adverse events.ConclusionsThe combination of oral calcium, vitamin D3 and DHA was safe, tolerable and acceptable when used for 12 months by osteopenic individuals in this pilot study. The combination had a positive effect on bone health as indicated by serum CTx, with no effect demonstrated from the addition of DHA 400 mg. Changes in BMD at the lumbar spine and TPF were significantly correlated with changes in CTx, which may be useful in monitoring bone health and response to treatment.