Evidence of a Positive Link between Consumption and Supplementation of Ascorbic Acid and Bone Mineral Density

Mariangela Rondanelli,Milena Faliva,Simone Perna,Maurizio Naso,Viviana Vecchio,Alice Tartara,Enrica Di Paolo,Gabriella Peroni,Mara Nichetti,Federica Fossari,Antonella Riva,Giovanna Petrangolini

doi:10.3390/nu13031012

Abstract

In animal models it has been shown that ascorbic acid (AA) is an essential cofactor for the hydroxylation of proline in collagen synthesis. However, there are still no precise indications regarding the role of AA in maintaining bone health in humans, so the aim of this narrative review was to consider state of the art on correlation between bone mineral density (BMD), AA dietary intake and AA blood levels, and on the effectiveness of AA supplement in humans. This review included 25 eligible studies. Fifteen studies evaluated correlations between AA intake and BMD: eight studies demonstrated a positive correlation between AA dietary intake and BMD in 9664 menopausal women and one significant interaction between effects of AA intake and hormone therapy. These data were also confirmed starting from adolescence (14,566 subjects). Considering studies on AA blood concentration and BMD, there are four (337 patients) that confirm a positive correlation. Regarding studies on supplementation, there were six (2671 subjects), of which one was carried out with AA supplementation exclusively in 994 postmenopausal women with a daily average dose of 745 mg (average period: 12.4 years). BMD values were found to be approximately 3% higher in women who took supplements.

Highlights

Ascorbic acid (AA), or vitamin C, is a water-soluble vitamin responsible for the biosynthesis of collagen, neurotransmitters, and L-carnitine
As for plasma levels of AA, Maggio and colleagues, in their cross-sectional case-control study conducted on 150 postmenopausal women aged ≥ 60 years, observed plasma levels of antioxidants, including AA, that were significantly lower in participants suffering from osteoporosis with T-score ≤ −3.5 compared to healthy controls (T-score ≥ −1, n = 75) [21]
Several other case-control studies investigated the existence of a relationship between hip fractures or other fragility fractures and serum concentrations of AA

Summary

Introduction

Ascorbic acid (AA), or vitamin C, is a water-soluble vitamin responsible for the biosynthesis of collagen, neurotransmitters, and L-carnitine. Fresh fruits and vegetables are the richest sources of AA, in particular peppers, kiwis, citrus fruits, strawberries, tomatoes and green leafy vegetables (such as field chicory and broccoli); this vitamin is added as an ingredient in many fruit juice-based drinks [2]. The average dietary intake of AA (60–100 mg/day) reflects a plasma level of approximately. The relationship between the dose taken and the plasma concentration of this vitamin was found to be of the sigmoidal type: intakes higher than 100 mg/day are beyond the linear portion of the curve, with plasma saturation and circulating cells for a dose between 200 and 400 mg/day, corresponding to concentrations of about 70–85 μM, with consequent urinary excretion of the vitamin [3]. Based on data collected through the National

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