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Introducción. El Síndrome Metabólico (SM) comprende un conjunto de factores de riesgo cardiometabólico representado por obesidad central, dislipidemia, hipertensión arterial y glucosa alterada, se ha evidenciado que el consumo adecuado de calcio representa una disminución del riesgo para este síndrome. Objetivo. Analizar la relación entre el consumo de calcio total, de origen animal y vegetal con el SM y sus indicadores. Materiales y métodos. Estudio transversal de eje correlacional, con una muestra de 100 adultos de la región amazónica ecuatoriana, durante el último trimestre del 2020. La ingesta dietética de calcio se determinó mediante un recordatorio de 24 horas y el SM según los criterios de Adult Treatment Panel-IV (ATP-IV). Resultados. La población estuvo conformada por adultos maduros (40 a 60 años) que evidenciaron una ingesta de calcio deficiente (182,50 mg y 228,60 mg en mujeres y hombres respectivamente). Se evidenció, además, una relación directamente proporcional entre la circunferencia abdominal (r=0,391 p=0,000), presión arterial sistólica (r=0,290 p=0,000) y glucosa en ayuno (r=0,326 p=0,000) con la edad. La ingesta de calcio total se relacionó positivamente con los triglicéridos, (r=0,221 p=0,027). Conclusiones. La ingesta dietética de calcio en ambos sexos no alcanza el requerimiento diario y se relaciona positivamente con los triglicéridos(AU)
Introduction. The Metabolic Syndrome (MS) comprises a set of cardiometabolic risk factors represented by central obesity, dyslipidemia, high blood pressure and altered glucose, it has been shown that adequate calcium intake represents a decreased risk for this syndrome. Objective. To analyze the relationship between the consumption of total calcium, animal and vegetable origin, with MS and its indicators. Materials and methods. Cross-sectional study of correlational axis, with a sample of 100 adults from the Ecuadorian Amazon region, during the last quarter of 2020. Dietary calcium intake was determined through a 24-hour recall and the diagnosis of MS according to the Adult Treatment Panel- IV (ATP-IV) criteria. Results. The population consisted of mature adults (40 to 60 years) who showed a deficient calcium intake in both sexes (182.50 mg and 228.60 mg in women and men respectively). There is also evidence of a directly proportional relationship between abdominal circumference (r=0.391 - p=0.000), systolic blood pressure (r=0.290 - p=0.000) and fasting glucose (r=0.326 - p=0.000) with age. Total calcium intake was positively related to triglycerides (r=0.221 p=0.027). Conclusions. Calcium dietary intake in both sexes does not reach the daily requirement and is positively related to triglycerides(AU)
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Cálcio/administração & dosagem , Fatores de Risco , Síndrome Metabólica/complicações , Diabetes Mellitus , Circunferência Abdominal , Dislipidemias , Hipertensão , ObesidadeRESUMO
SUMMARY OBJECTIVE: A significant problem that compels clinicians in the conventional treatment of hypoparathyroidism is patients' non-adherence to treatment. This study aimed to evaluate the effects of adequate Ca intake with dietary recommendations among hypoparathyroidism patients who persistently use Ca supplementation irregularly on plasma Ca and phosphate levels. METHODS: This prospective, randomized, controlled study was conducted on patients diagnosed with chronic hypoparathyroidism who persistently interrupt Ca supplementation therapy and therefore have a hypocalcemic course. Patients with a total daily Ca intake below 800 mg were randomized. All patients were advised to keep the doses of active vitamin D and Ca supplements they were currently using. The patients in the study group (n=32) were advised to consume 1,000-1,200 mg of Ca daily, and the patients in the control group (n=35) were advised to continue their diet according to their daily habits. After 12 weeks of follow-up, the patients' laboratory values were compared between groups to assess treatment goals. RESULTS: The mean of the total Ca level was 8.56±0.36 mg/dL in the study group and was found to be significantly higher than that in the control group, which was 7.67±0.48 mg/dL (p<0.001). The mean serum phosphate and serum Ca-P product levels were significantly higher in the study group (p<0.001) but did not exceed the safe upper limits in any patient. CONCLUSION: A suitable increase in dietary Ca intake could effectively control hypocalcemia in patients with hypoparathyroidism who persistently interrupt the recommended calcium supplementation.
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Ca2+ has an important role in the maintenance of the skeleton and is involved in the main physiological processes. Its homeostasis is controlled by the intestine, kidney, bone and parathyroid glands. The intestinal Ca2+ absorption occurs mainly via the paracellular and the transcellular pathways. The proteins involved in both ways are regulated by calcitriol and other hormones as well as dietary factors. Fibroblast growth factor 23 (FGF-23) is a strong antagonist of vitamin D action. Part of the intestinal Ca2+ movement seems to be vitamin D independent. Intestinal Ca2+ absorption changes according to different physiological conditions. It is promoted under high Ca2+ demands such as growth, pregnancy, lactation, dietary Ca2+ deficiency and high physical activity. In contrast, the intestinal Ca2+ transport decreases with aging. Oxidative stress inhibits the intestinal Ca2+ absorption whereas the antioxidants counteract the effects of prooxidants leading to the normalization of this physiological process. Several pathologies such as celiac disease, inflammatory bowel diseases, Turner syndrome and others occur with inhibition of intestinal Ca2+ absorption, some hypercalciurias show Ca2+ hyperabsorption, most of these alterations are related to the vitamin D endocrine system. Further research work should be accomplished in order not only to know more molecular details but also to detect possible therapeutic targets to ameliorate or avoid the consequences of altered intestinal Ca2+ absorption.
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Cálcio , Absorção Intestinal , Calcitriol , Cálcio/metabolismo , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Mucosa Intestinal/metabolismo , Intestinos , Gravidez , Vitamina D/metabolismoRESUMO
This study describes the median average intake of calcium in a population in Bogota, Colombia. Approximations on the possible reasons of low intake are listed. INTRODUCTION: The International Osteoporosis Foundation (IOF) published in 2017 the Calcium Map. It is a review of the calcium intake of 74 countries, placing Colombia in the bottom three countries of the world, with a daily calcium intake of 297 mg per day. The present study determined the actual median average calcium intake of a sample from Bogota and described it using sociodemographic variables. METHODS: In 2019, 450 anonymous volunteers who agreed to fill out the IOF Calcium Calculator survey were recruited. Measures of frequencies and percentage for qualitative variables were used, along with measures of central tendency with averages and dispersion for quantitative variables. Insufficient daily calcium intake was determined according to age, gender, and overall. RESULTS: The median average intake was 726 mg/day. Population between 18 and 30 years old had the highest intake per day. There were no significant differences between genders: women had a median average calcium intake of 731 mg/day, and for men it was 717.5 mg/day. Intake was directly correlated with socioeconomic status. CONCLUSIONS: Calcium intake in Colombia is low according to the age requirements and it is proportional to the socioeconomic status. Medical societies and national government should create policies in order to educate the general public and increase the intake of calcium based on diet.
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Cálcio/farmacologia , Osteoporose , Adolescente , Adulto , Cálcio da Dieta , Colômbia/epidemiologia , Dieta , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Recent studies suggest that supplemental Ca (SC) increases the risk of cardiovascular events, whereas dietary Ca (DC) decreases the risk of cardiovascular events. Although frequently consumed with meals, it remains unclear whether Ca can mitigate or aggravate the deleterious effects of a high-fat meal on cardiovascular risk factors. This study aimed to evaluate the effects of SC or DC on blood pressure (BP) and microvascular function (MVF) in the postprandial period in obese women challenged with a high-fat meal. In this cross-over controlled trial, sixteen obese women aged 20-50 years were randomly assigned to receive three test meals (2908 kJ (695 kcal); 48 % fat): high DC (HDCM; 547 mg DC), high SC (HSCM; 500 mg SC-calcium carbonate) and low Ca (LCM; 42 mg DC). BP was continuously evaluated from 15 min before to 120 min after meals by digital photoplethysmography. Before and 120 min after meals, participants underwent evaluation of serum Ca and microvascular flow after postocclusive reactive hyperaemia (PORH) by laser speckle contrast imaging. Ionised serum Ca rose significantly only after HSCM. Systolic BP increased after the three meals, whereas diastolic BP increased after LCM and HDCM. Hyperaemia peak, hyperaemia amplitude and AUC evaluated after PORH decreased with LCM. After HDCM, there was a reduction in hyperaemia peak and hyperaemia amplitude, whereas HSCM decreased only hyperaemia peak. However, comparative analyses of the effects of three test meals on serum Ca, BP and MVF revealed no significant meal×time interaction. This study suggests that in obese women SC and DC do not interfere with the effects of a high-fat meal on BP and MVF.
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Conservadores da Densidade Óssea/uso terapêutico , Cálcio da Dieta/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Laticínios , Suplementos Nutricionais , Microvasos/fisiopatologia , Obesidade/fisiopatologia , Adulto , Pressão Sanguínea , Índice de Massa Corporal , Conservadores da Densidade Óssea/efeitos adversos , Brasil/epidemiologia , Cálcio/sangue , Carbonato de Cálcio/administração & dosagem , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos Cross-Over , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Feminino , Antebraço , Frequência Cardíaca , Humanos , Hiperemia/etiologia , Hiperemia/prevenção & controle , Obesidade/sangue , Período Pós-Prandial , Fatores de RiscoRESUMO
ABSTRACT The proper dietary calcium intake and calcium supplementation, when indicated, are important factors in the acquisition of peak bone mass during youth and in the prevention of fractures in old age. In addition to its deposition in bone, calcium confers an increase in its resistance and exhibits important activities in different enzymatic pathways in the body (e.g., neural, hormonal, muscle-related and blood clotting pathways). Thus, calcium supplementation can directly or indirectly affect important functions in the body, such as the control of blood pressure, plasma glucose, body weight, lipid profile and endothelial function. Since one publication reported increased cardiovascular risk due to calcium supplementation, many researchers have studied whether this risk actually exists; the results are conflicting, and the involved mechanisms are uncertain. However, studies that have evaluated the influence of the consumption of foods rich in calcium have reported no increase in the cardiovascular risk, which suggests that nutritional intake should be prioritized as a method for supplementation and that the use of calcium supplements should be reserved for patients who truly need supplementation and are unable to achieve the recommended daily nutritional intake of calcium.
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Humanos , Osteoporose/prevenção & controle , Osso e Ossos/efeitos dos fármacos , Cálcio da Dieta/administração & dosagem , Doenças Cardiovasculares/induzido quimicamente , Suplementos Nutricionais/efeitos adversos , Conservadores da Densidade Óssea/administração & dosagem , Vitamina D/uso terapêutico , Cálcio da Dieta/efeitos adversos , Doenças Cardiovasculares/mortalidade , Densidade Óssea/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Metanálise como Assunto , Cálcio/uso terapêutico , Fatores de Risco , Fatores Etários , Fraturas Ósseas/prevenção & controle , Conservadores da Densidade Óssea/efeitos adversos , Recomendações NutricionaisRESUMO
The elevated prevalence of obesity worldwide is a challenging public health problem. Dietary calcium intake is frequently below recommendations, and evidence gathered for more than a decade suggests that inadequate calcium intake may be related to increased body weight and/or body fat, although a consensus has yet to be reached. Whole-body energy balance and the cellular mechanisms involved have been proposed to explain this relationship, and increasing evidence from epidemiological, clinical, and basic research lends support to the hypothesis that calcium is linked to the regulation of body weight. This review provides a critical appraisal of evidence from studies that examined several different aspects of this issue. Different mechanisms are highlighted and, based on recent work, new perspectives are offered, which incorporate the concept of obesity-associated inflammation and the possible role of the extracellular calcium-sensing receptor.
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Cálcio da Dieta/administração & dosagem , Obesidade/prevenção & controle , Receptores de Detecção de Cálcio/fisiologia , Tecido Adiposo/metabolismo , Animais , Peso Corporal , Metabolismo Energético , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Obesidade/dietoterapia , Obesidade/epidemiologia , Obesidade/metabolismo , Aumento de PesoRESUMO
Objetivo: Evaluar el estado nutricional del calcio en hombres jóvenes con diferentes grados de actividad física, mediante la estimación del consumo de calcio y de la masa mineral ósea total, con el fin de realizar recomendaciones que disminuyan el riesgo de osteoporosis. Métodos: Se realizó un estudio descriptivo y transversal en 80 hombres con edades entre 25 y 50 años, con distintos niveles de actividad física. La densidad mineral ósea (DMO) se determinó utilizando un densitómetro DEXA (Dual Energy X-ray Absorptiometry). La ingesta de calcio se midió a través de un cuestionario de frecuencia de consumo de alimentos semicuantitativa. El nivel de actividad física se determinó a través del cuestionario IPAQ (International Physical Activity Questionnaire). Resultados: En promedio, los hombres estudiados presentaron un consumo alto de calcio (1.926 mg/día), sin diferencias asociadas al nivel de actividad física. El valor promedio registrado para la DMO central fue de 1,147 g/cm² y para la DMO periférica fue de 0,993 g/cm². El 24% de los sujetos presentó valores de DMO por debajo del rango esperado para su edad y género. La DMO se asoció positivamente con el consumo de calcio (r=0,29; p < 0,01), mientras que la relación fue inversamente proporcional con la edad (r= - 0,42; p < 0,01). No se encontró relación entre la DMO ni central ni periférica, y el nivel de actividad física. Conclusión: Los valores bajos de densidad ósea observados en la población masculina joven estudiada sugieren que es necesario evaluar factores de riesgo asociados al estilo de vida, como el consumo de calcio y la actividad física.
Objective: To evaluate the calcium nutritional state in young men with different physical activity levels, through calcium intake and mineral density estimation, to make recommendations that could decrease the risk to develop osteoporosis. Methods: A cross-sectional study was designed with 80 men aged 25 to 50 and with different levels of physical activity. Bone mineral density (BMD) was established through DEXA (Dual Energy X-ray Absorptiometry) densitometry. A semi-quantitative food frequency questionnaire was designed to estimate calcium intake. Physical activity levels were established through IPAQ (International Physical Activity Questionnaire). Results: On average, the men that participated in the study had high calcium intakes (1.926 mg/day), with no differences associated with the level of physical activity. The average value recorded for the central BMD was 1.147 g/cm2 and for the peripheral BMD was 0.993 g/cm2. About 24% of the subjects had BMD values below the expected range for their age and gender. The BMD was positively associated with calcium intake (r=0.29; p < 0.01), while the association was inversely proportional to age (r= - 0.42; p < 0.01). No relationship was found between central or peripheral BMD, and physical activity level. Conclusions: Low values of bone density observed in the young male population studied suggest the need to assess risk factors associated with lifestyle, such as calcium intake and physical activity.
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The composition of urine is influenced by diet and changes in dietary factors have been proposed to modify the risk of recurrent nephrolithiasis. Nutrients that have been implicated include calcium, oxalate, sodium, animal protein, magnesium and potassium. There is significant evidence showing that a high calcium diet is associated with a reduction of lithogenic risk. One of the possible mechanisms to explain this apparent paradox is that the higher intake of calcium in the intestine binds with dietary oxalate, reducing its absorption and urinary excretion. Oxalate from the diet seems to provide only a small contribution to excretion and dietary restriction is appropriate only in those with hyperoxaluria and hyperabsorption. Observational studies have shown a positive and independent association between sodium intake and the formation of new kidney stones. Consumption of animal protein creates an acid load that increases urinary excretion of calcium and uric acid and reduced citrate, all factors that could participate in the genesis of stones. Potassium-rich foods increase urinary citrate because of its alkali content. In prospective observational studies, diets rich in magnesium were associated with a lower risk of kidney stone formation in men. In conclusion, diet is a key element in the management of the patient with kidney stones but always subordinated to present metabolic risk factors.
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Nefrolitíase/dietoterapia , Cálcio da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Humanos , Hiperoxalúria/etiologia , Nefrolitíase/fisiopatologia , Oxalatos/administração & dosagem , Sódio na Dieta/administração & dosagemRESUMO
Antecedentes: Aunque, el balance energético es el principal factor que regula el peso corporal, estudios recientes sugieren que el metabolismo del calcio puede modificar el balance energético y actuar en la regulación del mismo. Objetivo: Evaluar la asociación entre la ingesta de calcio dietético y el índice de masa corporal elevado en adultos mexicanos de 20 a 59 años. Material y métodos: Estudio secundario de tipo analítico, derivado de la Encuesta Nacional de Salud y Nutrición 2006. Se analizó la información del cuestionario de frecuencia de alimentos a 16.494 adultos. Después de eliminar valores biológicamente inadmisibles o casos con información incompleta, la muestra final fue de 15.662 adultos que se agruparon según su índice de masa corporal. Se utilizó regresión lineal para estimar la asociación entre ingesta de calcio dietético y el índice de masa corporal. Resultados: Hubo asociación inversa entre el consumo de calcio dietético e índice de masa corporal. Los sujetos con índice de masa corporal normal consumieron 903,9 mg/d versus 832,0 mg/d de calcio en obesos (p < 0,0001). Conclusión: Este estudio corrobora la evidencia existente de asociación inversa entre la ingesta de calcio dietético y el índice de masa corporal elevado.
Background. Although energy balance is the main factor that regulates body weight, recent studies suggest that calcium metabolism can modify the energy balance and help regulate body weight. Objective. To evaluate the association between the calcium intake in the diet and high body mass index in Mexican adults in the 20-59 age group. Material and methods. A cross-sectional secondary analytical study was conducted based on the 2006 Mexican National Health and Nutritional Survey (ENSANUT 2006). Food intake questionnaires applied to 16,494 adults were analyzed. After removing biologically implausible values or incomplete information, we arrived at a final sample of 15,662 adults grouped according to their body mass index. Linear regression was used to assess association between daily dietary calcium intake and body mass index. Results. There was an inverse association between dietary calcium consumption and a high body mass index. The mean calcium intake in subjects with normal body mass index was 903.9 mg/day versus 832.0 mg/day in obese subjects (p < 0.0001). Conclusion. The study corroborates existing evidence of an inverse association between the dietary calcium intake and a high body mass index.
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Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Índice de Massa Corporal , Cálcio da Dieta , Inquéritos Nutricionais , Antropometria , Estudos Transversais , Laticínios , México , Atividade Motora , Obesidade , Sobrepeso , Fatores Socioeconômicos , Interpretação Estatística de DadosRESUMO
Dietary intervention is an important approach in the prevention of cardiovascular disease. Over the last decade, some studies have suggested that a calcium-rich diet could help to control body weight, with anti-obesity effects. The potential mechanism underlying the impact of calcium on body fat has been investigated, but it is not fully understood. Recent evidence has also suggested that a calcium-rich diet could have beneficial effects on other cardiovascular risk factors, such as insulin resistance, dyslipidemia, hypertension and inflammatory states. In a series of studies, it was observed that a high intake of milk and/or dairy products (the main sources of dietary calcium) is associated with a reduction in the relative risk of cardiovascular disease. However, a few studies suggest that supplemental calcium (mainly calcium carbonate or citrate) may be associated with an increased risk of cardiovascular events. This review will discuss the available evidence regarding the relationship between calcium intake (dietary and supplemental) and different cardiovascular risk factors and/or events.
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Humanos , Cálcio da Dieta/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Laticínios , Cálcio da Dieta/efeitos adversos , Fatores de RiscoRESUMO
Epidemiological studies show that a high calcium intake reduces the risk of colon cancer. The objective was to study the association between calcium intake and colorectal neoplasia in a clinic-based sample of Hispanics adults from Puerto Rico. As part of this cross-sectional study, a total of 433 subjects were recruited from surgery and gastroenterology clinics at the University of Puerto Rico. Calcium intake was estimated using a food frequency questionnaire (FFQ) of calcium rich foods. Socio-demographics, health history and colonoscopy results were obtained from the primary study. Chi square and odds ratios (OR) for colorectal neoplasia (adenomas and/or adenocarcinoma) were calculated for total calcium, dietary calcium and for calcium supplement use. In total, 312 (72%) from 433 participants completed the FFQ and had available colonoscopy results; from these, 196 (62.5%) were free of neoplasia and 117 (37.5%) had colorectal neoplasia. Colorectal neoplasia subjects were older, a lower proportion were females and less educated than those without neoplasia (p<0.01). Total calcium intake (median 1180 mg/d) was greater in those free of neoplasia compared to colorectal neoplasia subjects (median 1036 mg/d; p<0.05). A high total calcium intake and the use of calcium supplements significantly reduced the OR (crude and age adjusted) for colorectal neoplasia; although these associations lost statistical significance after additionally adjusting for gender and educational level. In conclusion, a high calcium intake and the use of calcium supplements may be protective against colorectal neoplasia, although a greater sample may be required to observe significant associations in a multivariate model.
Los estudios muestran que un alto consumo de calcio reduce el riesgo de cáncer de colon. El objetivo del presente estudio fue estudiar la asociación entre el consumo de calcio y la neoplasia colorrectal en una muestra de hispanos adultos en Puerto Rico. Un total de 433 sujetos fueron reclutados de las clínicas de cirugía y gastroenterología de la Universidad de Puerto Rico. El consumo de calcio fue estimado usando un cuestionario de frecuencia de consumo (CFC) de alimentos ricos en calcio. Los datos socio-demográficos y la colonoscopia se obtuvieron del estudio principal. Se calculó el Ji² y la razón de productos cruzados de neoplasia colorrectal por el consumo total, dietético y uso de suplementos de calcio. Un total de 312 (72%) de 433 participantes completaron el estudio; de éstos, 196 (62.5%) estaban libres de neoplasia y 117 (37.5%) tenían neoplasia colorrectal, los cuales eran de mayor edad, con menor proporción de mujeres y menos educados que aquellos sin neoplasia (p<0.01). El consumo total de calcio (mediana 1180 mg/d) fue mayor en sujetos sin neoplasia que los sujetos con neoplasia (mediana 1036 mg/d; p<0.05). Un alto consumo total de calcio y el uso de suplementos de calcio redujo significativamente la posibilidad (crudo y ajustado por edad) de neoplasia colorrectal; aunque no fue significativo cuando se ajusto también por género y educación. En conclusión, un alto consumo de calcio y el uso de suplementos de calcio pueden proteger contra la neoplasia colorrectal, aunque se requieren más sujetos para ver asociaciones significativas en el modelo multivariado.
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Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cálcio da Dieta/administração & dosagem , Neoplasias Colorretais/epidemiologia , Suplementos Nutricionais , Colonoscopia , Estudos Transversais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Registros de Dieta , Porto Rico/epidemiologiaRESUMO
O cálcio (Ca) dietético é fundamental para a saúde óssea. Tanto o teor como a biodisponibilidade do elemento nos alimentos devem ser considerados. Este artigo objetiva sumarizar os fatores envolvidos na absorção e destacar os alimentos com melhor disponibilidade do Ca. Este é absorvido principalmente no jejuno e o pH baixo parece favorecer sua absorção, que é maior no crescimento, na gestação/lactação e na carência de Ca ou fósforo (P), e menor no envelhecimento. As maiores fontes, e com melhor absorção, são os laticínios bovinos. Outros alimentos apresentam concentrações elevadas de Ca, mas com biodisponibilidade variável: os ricos em ácidos oxálico e fítico apresentariam uma menor absorção, enquanto que os ricos em carboidratos teriam uma absorção maior. Por apresentarem uma biodisponibilidade do Ca mais próxima da do leite bovino, o leite de outros animais, o de soja enriquecido e alguns vegetais, em quantidades adequadas, poderiam ser usados como alternativas a este.
Dietary calcium (Ca) is fundamental to the bone's health. Both the purport and the element bioavailability in the food need to be considered. The purpose of this work was to summarize the factors involved in Ca absorption and point out the sources with higher bioavailability. Ca is mostly absorbed in the jejunum and low pH seems to favor its absorption, which is higher during growth, gestation/lactation and Ca and phosphorus (P) deficiency, and lower with aging. The richest and best-absorbed Ca source is cow's milk and its derivatives. Other foods show high Ca concentrations but variable bioavailability: foods rich in phytates and oxalates show a smaller absorption and carbohydrate-rich foods show higher absorption. Since Ca bioavailability in other animal's milk, soymilk and some vegetables is closer to that in cow's milk, adequate amounts of these foods could be used as an alternative.