Mediterranean diet and high dietary acid load associated with mixed nuts: effect on bone metabolism in elderly subjects.
Objectives: To analyze the effect of differing diet on the acid load content on bone metabolism.
Design: Multicentric, randomized, single-blind, parallel-group clinical trial.
Setting: Outpatient clinics.
Two hundred thirty-eight elderly men and women aged 60 to 80 at high risk for cardiovascular disease were randomly assigned to three interventional groups: a recommended low-fat diet (control diet group), a Mediterranean diet supplemented with virgin olive oil, or a Mediterranean diet supplemented with mixed nuts.
Main outcomes were 12-month changes from baseline in bone formation and resorption markers and bone mass measured according to quantitative ultrasound scanning.
The baseline data on the anthropometric, bone densitometry, and biochemical variables did not differ between the three groups. Dietary potential renal acid load (PRAL) and daily net endogenous acid production (NEAP) at baseline did not differ between groups. After intervention, subjects allocated to the Mediterranean diet with mixed nuts had a significant increase of PRAL and NEAP. In comparison, subjects in the Mediterranean diet with nuts group had higher parathyroid hormone (PTH) levels (2.63, 95% confidence interval (CI)=-1.01-6.35, P=.02) and a nonsignificantly higher (0.31, 95% CI=-0.13-0.74, P=.14) urine free deoxypyridoxine:creatinine ratio, a marker of bone resorption, than the control group and the Mediterranean diet with virgin olive oil group.
A Mediterranean dietary pattern associated with a high dietary acid load derived from consumption of mixed nuts does not seem to have a much greater effect on bone metabolism biomarkers, with the exception of PTH levels, than a Mediterranean diet without mixed nuts or a control diet in elderly subjects.
Bulló M, Amigó-Correig P, Márquez-Sandoval F, Babio N…
J Am Geriatr Soc Oct 2009
Olive polyphenol hydroxytyrosol prevents bone loss.
Polyphenols reportedly exert physiological effects against diseases such as cancer, arteriosclerosis, hyperlipidemia and osteoporosis. The present study was designed to evaluate the effects of oleuropein, hydroxytyrosol and tyrosol, the major polyphenols in olives, on bone formation using cultured osteoblasts and osteoclasts, and on bone loss in ovariectomized mice. No polyphenols markedly affected the proliferation of osteoblastic MC3T3-E1 cells at concentrations up to 10μM. Oleuropein and hydroxytyrosol at 10 to 100μM had no effect on the production of type I collagen and the activity of alkaline phosphatase in MC3T3-E1 cells, but stimulated the deposition of calcium in a dose-dependent manner. In contrast, oleuropein at 10 to 100μM and hydroxytyrosol at 50 to 100μM inhibited the formation of multinucleated osteoclasts in a dose-dependent manner. Furthermore, both compounds suppressed the bone loss of trabecular bone in femurs of ovariectomized mice (6-week-old BALB/c female mice), while hydroxytyrosol attenuated H(2)O(2) levels in MC3T3-E1 cells. Our findings indicate that the olive polyphenols oleuropein and hydroxytyrosol may have critical effects on the formation and maintenance of bone, and can be used as effective remedies in the treatment of osteoporosis symptoms.
Hagiwara K, Goto T, Araki M, Miyazaki H…
Eur. J. Pharmacol. Jul 2011
A Mediterranean diet enriched with olive oil is associated with higher serum total osteocalcin levels in elderly men at high cardiovascular risk.
The intake of olive oil has been related to the prevention of osteoporosis in experimental and in in vitro models. Very few prospective studies have evaluated the effects of olive oil intake on circulating osteocalcin (OC) in humans.
The objective of the study was to examine the longitudinal effects of a low-fat control diet (n=34), a Mediterranean diet enriched with nuts (MedDiet+nuts, n=51), or a Mediterranean diet enriched with virgin olive oil (MedDiet+VOO, n=42) on circulating forms of OC and bone formation markers in elderly men at high cardiovascular risk.
Longitudinal associations between baseline and follow-up (2 yr) measurements of total OC, undercarboxylated osteocalcin, C-telopeptide of type I collagen, and procollagen I N-terminal propeptide (P1NP) concentrations were examined in 127 elderly men randomized to three healthy dietary interventions.
Baseline characteristics (age, body mass index, waist circumference, lipid profile, fasting insulin levels, and bone formation and resorption markers) were similar in all intervention groups. The total osteocalcin concentration increased robustly in the MedDiet+VOO group (P=0.007) in parallel to increased P1NP levels (P=0.01) and homeostasis model assessment-β-cell function (P=0.01) but not in subjects on the MedDiet+nuts (P=0.32) or after the control diet (P=0.74). Interestingly, the consumption of olives was associated positively with both baseline total osteocalcin (r=0.23, P=0.02) and the 2-yr osteocalcin concentrations (r=0.21, P=0.04) in the total cohort.
Consumption of a Mediterranean diet enriched with virgin olive oil for 2 years is associated with increased serum osteocalcin and P1NP concentrations, suggesting protective effects on bone.
Fernández-Real JM, Bulló M, Moreno-Navarrete JM, Ricart W…
J. Clin. Endocrinol. Metab. Oct 2012
Interestingly, nuts did not show a benefit.
Oleuropein enhances osteoblastogenesis and inhibits adipogenesis: the effect on differentiation in stem cells derived from bone marrow.
The effects of oleuropein on the processes of osteoblastogenesis and adipogenesis in mesenchymal stem cells (MSCs) from human bone marrow have been studied. We report that oleuropein, a polyphenol abundant in olive tree products, reduces the expression of peroxisome proliferator-activated receptor gamma (PPARγ), inhibits adipocyte differentiation, and enhances differentiation into osteoblast.
Age-related bone loss is associated with osteoblast insufficiency during continuous bone remodeling. It has been suggested that the formation of osteoblasts in bone marrow is closely associated with adipogenesis, and age-related changes in this relationship could be responsible for the progressive adiposity of bone marrow which occurs with osteoporosis. In addition, the consumption of oleuropein, a major polyphenol in olive leaves and olive oil, has been associated with a reduction in bone loss.
We have analyzed the effects of oleuropein-at concentrations between 10(-6) and 10(-4) M-on the processes of osteoblastogenesis and adipogenesis in MSCs from human bone marrow.
The results show an increase in osteoblast differentiation and a decrease in adipocyte differentiation when there is oleuropein in the culture media. The gene expression of osteoblastogenesis markers, RUNXII, osterix, collagen type I, osteocalcin, or alkaline phosphatase (ALP), was higher in osteoblast-induced oleuropein-treated cells. Also, the ALP activity and extracellular matrix mineralization were higher when oleuropein was present in the media. Oleuropein in MSCs induced adipocytes to produce a decrease in the expression of the genes involved in adipogenesis, the PPARγ, lipoprotein lipase, or fatty acid-binding protein 4, and minor fat accumulation.
Our data suggest that oleuropein, highly abundant in olive tree products included in the traditional Mediterranean diet, could prevent age-related bone loss and osteoporosis.
Santiago-Mora R, Casado-Díaz A, De Castro MD, Quesada-Gómez JM
Osteoporos Int Feb 2011
Olive oil effectively mitigates ovariectomy-induced osteoporosis in rats.
Osteoporosis, a reduction in bone mineral density, represents the most common metabolic bone disease. Postmenopausal women are particularly susceptible to osteoporosis when their production of estrogen declines. For these women, fracture is a leading cause of morbidity and mortality. This study was conducted to evaluate the protective effects of olive oil supplementation against osteoporosis in ovariectomized (OVX) rats.
We studied adult female Wistar rats aged 12-14 months, divided into three groups: sham-operated control (SHAM), ovariectomized (OVX), and ovariectomized rats supplemented with extravirgin olive oil (Olive-OVX) orally for 12 weeks; 4 weeks before ovariectomy and 8 weeks after. At the end of the experiment, blood samples were collected. Plasma levels of calcium, phosphorus, alkaline phosphatase (ALP), malondialdehyde (MDA), and nitrates were assayed. Specimens from both the tibia and the liver were processed for light microscopic examination. Histomorphometric analysis of the tibia was also performed.
The OVX-rats showed a significant decrease in plasma calcium levels, and a significant increase in plasma ALP, MDA, and nitrates levels. These changes were attenuated by olive oil supplementation in the Olive-OVX rats. Light microscopic examination of the tibia of the OVX rats revealed a significant decrease in the cortical bone thickness (CBT) and the trabecular bone thickness (TBT). In addition, there was a significant increase in the osteoclast number denoting bone resorption. In the Olive-OVX rats these parameters were markedly improved as compared to the OVX group. Examination of the liver specimens revealed mononuclear cellular infiltration in the portal areas in the OVX-rats which was not detected in the Olive-OVX rats.
Olive oil effectively mitigated ovariectomy-induced osteoporosis in rats, and is a promising candidate for the treatment of postmenopausal osteoporosis.
Saleh NK, Saleh HA
BMC Complement Altern Med 2011
PMID: 21294895 | Free Full Text
Association between dietary patterns and indices of bone mass in a sample of Mediterranean women.
A holistic dietary approach, examining the effect of dietary patterns in terms of chronic disease prevention and treatment, continuously gains more attention and may elucidate the association between diet and bone health. In the present study we examined whether adherence to a Mediterranean diet or other dietary patterns has any significant impact on indices of bone mass.
Two hundred twenty adult Greek women were recruited. Lumbar spine bone mineral density and total body bone mineral content were determined by using dual x-ray absorptiometry. Food intake was assessed using 3-d food records and adherence to the Mediterranean diet was evaluated through a Mediterranean diet score. Principal components analysis was used for the identification of participants’ dietary patterns.
Adherence to a Mediterranean diet was not found to have any significant effect on indices of bone mass. Principal components analysis identified 10 dietary patterns explaining 80% of the variance in food intake. A pattern characterized by high consumption of fish and olive oil and low intake of red meat was positively associated with lumbar spine bone mineral density (P = 0.017) and total body bone mineral content (P = 0.048), after controlling for several confounders.
Adherence to a Mediterranean dietary pattern was not associated with indices of bone mass in a sample of adult women, whereas adherence to a dietary pattern close to the Mediterranean diet, i.e., high consumption of fish and olive oil and low red meat intake, was positively related to bone mass, suggesting potential bone-preserving properties of this pattern throughout adult life.
Kontogianni MD, Melistas L, Yannakoulia M, Malagaris I…
Nutrition Feb 2009
Major phenolic compounds in olive oil modulate bone loss in an ovariectomy/inflammation experimental model.
This study was conducted to determine whether the daily consumption for 84 days of tyrosol and hydroxytyrosol, the main olive oil phenolic compounds, and olive oil mill wastewater (OMWW), a byproduct of olive oil production, rich in micronutrients, may improve bone loss in ovariectomized rats (an experimental model of postmenopausal osteoporosis) and in ovariectomized rats with granulomatosis inflammation (a model set up for senile osteoporosis). As expected, an induced chronic inflammation provoked further bone loss at total, metaphyseal, and diaphyseal sites in ovariectomized rats. Tyrosol and hydroxytyrosol prevented this osteopenia by increasing bone formation ( p < 0.05), probably because of their antioxidant properties. The two doses of OMWW extracts had the same protective effect on bone ( p < 0.05), whereas OMWW did not reverse established osteopenia. In conclusion, polyphenol consumption seems to be an interesting way to prevent bone loss.
Puel C, Mardon J, Agalias A, Davicco MJ…
J. Agric. Food Chem. Oct 2008