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Nutrients Feb 2020Calcium is the main mineral in the body [...].
Calcium is the main mineral in the body [...].
Topics: Adiposity; Body Mass Index; Calcium; Female; Health; Homeostasis; Humans; Male; Periodicals as Topic; Public Health; Vitamin D
PubMed: 32041090
DOI: 10.3390/nu12020416 -
Nutrients Dec 2021This article reviews physicochemical aspects of calcium absorption from foods. Notable differences are observed between different food products in relation to calcium... (Review)
Review
This article reviews physicochemical aspects of calcium absorption from foods. Notable differences are observed between different food products in relation to calcium absorption, which range from <10% to >50% of calcium in the foods. These differences can be related to the interactions of calcium with other food components in the food matrix, which are affected by various factors, including fermentation, and how these are affected by the conditions encountered in the gastrointestinal tract. Calcium absorption in the intestine requires calcium to be in an ionized form. The low pH in the stomach is critical for solubilization and ionization of calcium salts present in foods, although calcium oxalate complexes remain insoluble and thus poorly absorbable. In addition, the rate of gastric transit can strongly affect fractional absorption of calcium and a phased release of calcium into the intestine, resulting in higher absorption levels. Dairy products are the main natural sources of dietary calcium in many diets worldwide, which is attributable to their ability to provide high levels of absorbable calcium in a single serving. For calcium from other food products, lower levels of absorbable calcium can limit contributions to bodily calcium requirements.
Topics: Calcium; Calcium, Dietary; Eating; Food; Food Analysis; Gastric Acid; Gastrointestinal Tract; Hydrogen-Ion Concentration; Intestinal Absorption; Ions; Nutritional Physiological Phenomena; Nutritional Requirements; Solubility
PubMed: 35011055
DOI: 10.3390/nu14010180 -
Journal of Clinical Hypertension... Jun 2017Over the past decade, the number of individuals taking calcium supplementation worldwide has been on the rise, especially with the emergence of new pharmaceutical... (Review)
Review
Over the past decade, the number of individuals taking calcium supplementation worldwide has been on the rise, especially with the emergence of new pharmaceutical companies specialized in the marketing of dietary supplements; with calcium supplementation being their main business axis. This is mostly because of the established role of calcium in the prevention and treatment of osteoporosis and, to a lesser extent, its role in the prevention of fractures. Recently, a rising body of evidence on the adverse effect of calcium supplementation on nonskeletal, especially cardiovascular, health has been a cause for concern. In fact, a significant number of studies have reported an association between calcium supplementation and adverse cardiovascular events, even though high dietary calcium intake was shown to have a protective effect. The mechanism by which calcium supplementation could cause a cardiovascular event was still unclear until a recent study published in the Journal of the American Heart Association. Combining this recent finding with available data associating calcium supplementation with cardiovascular mortality and all-cause mortality, we call on the need for an evidence-based approach to calcium supplementation, while stressing on the safety of dietary calcium intake over the former on cardiovascular health.
Topics: Aged; Blood Pressure; Calcium; Calcium, Dietary; Cardiovascular Diseases; Dietary Supplements; Female; Fractures, Bone; Humans; Hypertension; Male; Middle Aged; Osteoporosis; Randomized Controlled Trials as Topic; Risk Factors
PubMed: 28466573
DOI: 10.1111/jch.13010 -
Nutrients Jan 2021Calcium supplementation and fortification are strategies widely used to prevent adverse outcome in population with low-calcium intake which is highly frequent in... (Meta-Analysis)
Meta-Analysis Review
Calcium supplementation and fortification are strategies widely used to prevent adverse outcome in population with low-calcium intake which is highly frequent in low-income settings. We aimed to determine the effectiveness and cost-effectiveness of calcium fortified foods on calcium intake and related health, or economic outcomes. We performed a systematic review and meta-analysis involving participants of any age or gender, drawn from the general population. We searched PubMed, Agricola, EMBASE, CINAHL, Global Health, EconLit, the FAO website and Google until June 2019, without language restrictions. Pair of reviewers independently selected, extracted data and assessed the risk of bias of included studies using Covidence software. Disagreements were resolved by consensus. We performed meta-analyses using RevMan 5.4 and subgroup analyses by study design, age group, and fortification levels. We included 20 studies of which 15 were randomized controlled trials (RCTs), three were non-randomised studies and two were economic evaluations. Most RCTs had high risk of bias on randomization or blinding. Most represented groups were women and children from 1 to 72 months, most common intervention vehicles were milk and bakery products with a fortification levels between 96 and 1200 mg per 100 g of food. Calcium intake increased in the intervention groups between 460 mg (children) and 1200 mg (postmenopausal women). Most marked effects were seen in children. Compared to controls, height increased 0.83 cm (95% CI 0.00; 1.65), plasma parathyroid hormone decreased -1.51 pmol/L, (-2.37; -0.65), urine:calcium creatinine ratio decreased -0.05, (-0.07; -0.03), femoral neck and hip bone mineral density increased 0.02 g/cm (0.01; 0.04) and 0.03 g/cm (0.00; 0.06), respectively. The largest cost savings (43%) reported from calcium fortification programs came from prevented hip fractures in older women from Germany. Our study highlights that calcium fortification leads to a higher calcium intake, small benefits in children's height and bone health and also important evidence gaps for other outcomes and populations that could be solved with high quality experimental or quasi-experimental studies in relevant groups, especially as some evidence of calcium supplementation show controversial results on the bone health benefit on older adults.
Topics: Aged; Bone Density; Calcium; Calcium, Dietary; Child; Child, Preschool; Female; Food, Fortified; Hip Fractures; Humans; Infant; Male
PubMed: 33499250
DOI: 10.3390/nu13020316 -
Nutrients Dec 2018Calcium is an essential element that plays numerous biological functions in the human body, of which one of the most important is skeleton mineralization. Bone is a... (Review)
Review
Calcium is an essential element that plays numerous biological functions in the human body, of which one of the most important is skeleton mineralization. Bone is a mineralized connective tissue in which calcium represents the major component, conferring bone strength and structure. Proper dietary calcium intake is important for bone development and metabolism, and its requirement can vary throughout life. The mineral composition of drinking water is becoming relevant in the modulation of calcium homeostasis. In fact, calcium present in mineral drinking waters is an important quantitative source of calcium intake. This, together with its excellent bioavailability, contributes to the maintenance of the bone health. This article aims to examine studies that assessed the bioavailability of the calcium contained in calcium-rich mineral waters and their impact on bone health, including original data collected in a recent study in humans.
Topics: Bone Density; Bone and Bones; Calcium; Humans; Mineral Waters; Recommended Dietary Allowances
PubMed: 30563174
DOI: 10.3390/nu10121930 -
International Journal of Molecular... Mar 2019As a secondary messenger, calcium participates in various physiological and biochemical reactions in plants. Photosynthesis is the most extensive biosynthesis process on... (Review)
Review
As a secondary messenger, calcium participates in various physiological and biochemical reactions in plants. Photosynthesis is the most extensive biosynthesis process on Earth. To date, researchers have found that some chloroplast proteins have Ca-binding sites, and the structure and function of some of these proteins have been discussed in detail. Although the roles of Ca signal transduction related to photosynthesis have been discussed, the relationship between calcium and photosynthesis is seldom systematically summarized. In this review, we provide an overview of current knowledge of calcium's role in photosynthesis.
Topics: Calcium; Carbon; Chloroplasts; Light; Photosynthesis; Plant Stomata
PubMed: 30889814
DOI: 10.3390/ijms20061353 -
Molecules (Basel, Switzerland) May 2020Calcium controls numerous biological processes by interacting with different classes of calcium binding proteins (CaBP's), with different affinities, metal... (Review)
Review
Calcium controls numerous biological processes by interacting with different classes of calcium binding proteins (CaBP's), with different affinities, metal selectivities, kinetics, and calcium dependent conformational changes. Due to the diverse coordination chemistry of calcium, and complexity associated with protein folding and binding cooperativity, the rational design of CaBP's was anticipated to present multiple challenges. In this paper we will first discuss applications of statistical analysis of calcium binding sites in proteins and subsequent development of algorithms to predict and identify calcium binding proteins. Next, we report efforts to identify key determinants for calcium binding affinity, cooperativity and calcium dependent conformational changes using grafting and protein design. Finally, we report recent advances in designing protein calcium sensors to capture calcium dynamics in various cellular environments.
Topics: Animals; Binding Sites; Biosensing Techniques; Calcium; Calcium-Binding Proteins; Humans; Models, Molecular; Protein Binding; Protein Conformation; Protein Engineering; Protein Folding; Research
PubMed: 32375353
DOI: 10.3390/molecules25092148 -
Japanese Journal of Medicine 1990
Topics: Aging; Calcium; Humans
PubMed: 2214339
DOI: 10.2169/internalmedicine1962.29.1 -
Lancet (London, England) Jul 1998Abnormalities in serum calcium concentration may have profound effects on neurological, gastrointestinal, and renal function. Maintenance of the normal serum calcium is... (Review)
Review
Abnormalities in serum calcium concentration may have profound effects on neurological, gastrointestinal, and renal function. Maintenance of the normal serum calcium is a result of tightly regulated ion transport by the kidney, intestinal tract, and bone, mediated by calcaemic hormones especially parathyroid hormone and 1,25-dihydroxyvitamin D3. Abnormalities in calcium transport that result in uncompensated influx into, or efflux from, the extracellular fluid, will result in hypercalcaemia or hypocalcaemia, respectively. When possible the biologically important ionised calcium concentration should be measured. A variety of common disorders are responsible for abnormalities in the serum calcium. Treatment of both hypercalcaemia and hypocalcaemia is dependent on the underlying disorder, the magnitude of the deviation of the serum calcium, and the severity of symptoms. Fortunately, in the case of hypercalcaemia, there is a broad selection of effective medications, especially the bisphosphonates. Treatment of hypocalcaemia relies on the provision of calcium and often vitamin D. In this article we review the mechanisms responsible for abnormalities in calcium homoeostasis, the differential diagnosis of hypercalcaemia and hypocalcaemia, and appropriate therapy.
Topics: Calcium; Diagnosis, Differential; Homeostasis; Humans; Hypercalcemia; Hypocalcemia
PubMed: 9690425
DOI: 10.1016/s0140-6736(97)12331-5 -
International Journal of Molecular... Dec 2023Calcium research, since its pivotal discovery in the early 1800s through the heating of limestone, has led to the identification of its multi-functional roles. These... (Review)
Review
Calcium research, since its pivotal discovery in the early 1800s through the heating of limestone, has led to the identification of its multi-functional roles. These include its functions as a reducing agent in chemical processes, structural properties in shells and bones, and significant role in cells relating to this review: cellular signaling. Calcium signaling involves the movement of calcium ions within or between cells, which can affect the electrochemical gradients between intra- and extracellular membranes, ligand binding, enzyme activity, and other mechanisms that determine cell fate. Calcium signaling in muscle, as elucidated by the sliding filament model, plays a significant role in muscle contraction. However, as organisms age, alterations occur within muscle tissue. These changes include sarcopenia, loss of neuromuscular junctions, and changes in mineral concentration, all of which have implications for calcium's role. Additionally, a field of study that has gained recent attention, cellular senescence, is associated with aging and disturbed calcium homeostasis, and is thought to affect sarcopenia progression. Changes seen in calcium upon aging may also be influenced by its crosstalk with other minerals such as iron and zinc. This review investigates the role of calcium signaling in aging muscle and cellular senescence. We also aim to elucidate the interactions among calcium, iron, and zinc across various cells and conditions, ultimately deepening our understanding of calcium signaling in muscle aging.
Topics: Humans; Calcium; Sarcopenia; Cellular Senescence; Minerals; Muscle, Skeletal; Iron; Zinc
PubMed: 38069357
DOI: 10.3390/ijms242317034