The study – published in the Journal of Clinical Endocrinology and Metabolism – investigated of various low fat and Mediterranean style diets on markers for bone health and bone formation in elderly people.
Led by Dr José Manuel Fernández-Real of of Hospital Dr. Josep Trueta, Spain, the research team reveal that consumption of a Mediterranean diet enriched with olive oil for two years was associated with increased serum concentrations of bone formation markers (osteocalcin), suggesting a protective effect on bone health by increasing the formation of healthy bone.
"The intake of olive oil has been related to the prevention of osteoporosis in experimental and in vitro models," said Fernández-Real. "This is the first randomized study which demonstrates that olive oil preserves bone, at least as inferred by circulating bone markers, in humans."
The research team examined the effects of three set diets on markers of bone health and formation over a two year period in 127 community-dwelling men aged between 55 and 80 years.
The participants were selected from one of the Prevencion con Dieta Mediterranea (PREDIMED) study centers. The PREDIMED study is a large, parallel group, randomized, controlled trial aimed to assess the effect of the Mediterranean diet on the prevention of cardiovascular diseases. All had at least two years of follow-up.
A low-fat ‘control’ diet was received by 34 participants, whilst 51 received a Mediterranean diet enriched with nuts, and a further 42 followed a Mediterranean diet enriched with virgin olive oil.
The participants in this study were 127 community-dwelling men aged 55 to 80 years randomly selected from one of the Prevencion con Dieta Mediterranea (PREDIMED) study centers who had at least two years of follow-up. The PREDIMED study is a large, parallel group, randomized, controlled trial aimed to assess the effect of the Mediterranean diet on the prevention of cardiovascular diseases.
Biochemical measurements of osteocalcin, glucose, total cholesterol, HDL-cholesterol and triglycerides were performed at baseline and after two year follow-up on fasting blood samples.
Fernández-Real and his team found that only consumption of the Mediterranean diet with olive oil was associated with a significant increase in the concentrations of total osteocalcin and other bone formation markers.
There were also no significant changes in serum calcium in subjects taking olive oil whereas serum calcium decreased significantly in the other two groups, they added.
"It's important to note that circulating osteocalcin was associated with preserved insulin secretion in subjects taking olive oil," added Fernández-Real.
"Osteocalcin has also been described to increase insulin secretion in experimental models," he added.
Source: Journal of Clinical Endocrinology and Metabolism
Published online before print, doi:10.1210/jc.2012-2221
“A Mediterranean Diet Enriched with Olive Oil Is Associated with Higher Serum Total Osteocalcin Levels in Elderly Men at High Cardiovascular Risk.”
Authors: Fernández-Real JM, Bulló M, Moreno-Navarrete JM, Ricart W, Ros E, Estruch R, Salas-Salvadó J.