Interventions to improve calcium intake through foods in populations with low intake

Calcium supplementation for people with overweight or obesity

BACKGROUND

Obesity is a major health problem worldwide as it can lead to high blood pressure, heart disease, stroke, diabetes, and insulin resistance. The prevalence of overweight and obesity is increasing worldwide across different age groups. There is evidence of an inverse relationship between calcium intake and body weight. The clinical relevance of a small reduction in body weight has been questioned. However, at a population level, a small effect could mitigate the observed global trends.

OBJECTIVES

To assess the effects of calcium supplementation on weight loss in individuals living with overweight or obesity.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS (Latin American and Caribbean Health Science Information database), and two clinical trials registries. The date of the last search of all databases (except Embase) was 10 May 2023. No language restrictions were applied.

SELECTION CRITERIA

We included randomised controlled trials evaluating the effect of calcium in participants with overweight or obesity of any age or gender. We excluded studies in participants with absorption problems. We included studies of any dose with a minimum duration of two months. We included the following comparisons: calcium supplementation versus placebo, calcium-fortified food or beverage versus placebo, or calcium-fortified food or beverage versus non-calcium-fortified food or beverage. We excluded studies that evaluated the effect of calcium and vitamin D or mixed minerals compared to placebo.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were body weight, health-related quality of life, and adverse events. Our secondary outcomes were anthropometric measures other than body weight, all-cause mortality, and morbidity.

MAIN RESULTS

We found 18 studies that evaluated the effect of calcium compared to placebo or control, with a total of 1873 randomised participants (950 participants in the calcium supplementation groups and 923 in the control groups). All included studies gave oral calcium supplementation as the intervention. We did not find any studies evaluating calcium-fortified foods. We excluded 38 studies, identified four ongoing studies, and listed one study as 'awaiting classification'. Sixteen studies compared calcium supplementation to placebo; two studies compared different doses of calcium supplementation. Doses ranged from very low (0.162 g of calcium/day) to high (1.5 g of calcium/day). Most studies were performed in the USA and Iran, lasted less than six months, and included only women. Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in little to no difference in body weight (mean difference (MD) -0.15 kg, 95% confidence interval (CI) -0.55 to 0.24; P = 0.45, I2 = 46%; 17 studies, 1317 participants; low-certainty evidence). We downgraded the certainty of the evidence by two levels for risk of bias and heterogeneity. None of the included studies reported health-related quality of life, all-cause mortality, or morbidity/complications as outcomes. Only five studies assessed or reported adverse events. Low-certainty evidence suggests a low frequency of adverse events, with no clear difference between intervention and control groups. Moderate-certainty evidence shows that calcium supplementation compared to placebo or control probably results in a small reduction in body mass index (BMI) (MD -0.18 kg/m2,95% CI -0.22 to -0.13; P < 0.001, I2 = 0%; 9 studies, 731 participants) and waist circumference (MD -0.51 cm, 95% CI -0.72 to -0.29; P < 0.001, I2 = 0%; 6 studies, 273 participants). Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in a small reduction in body fat mass (MD -0.34 kg, 95% CI -0.73 to 0.05; P < 0.001, I2 = 97%; 12 studies, 812 participants).

AUTHORS' CONCLUSIONS

Calcium supplementation for eight weeks to 24 months may result in little to no difference in body weight in people with overweight or obesity. The current evidence is of low certainty, due to concerns regarding risk of bias and statistical heterogeneity. We found that the degree of heterogeneity might be partly explained by calcium dosage, the presence or absence of a co-intervention, and whether an intention-to-treat analysis was pursued. While our analyses suggest that calcium supplementation may result in a small reduction in BMI, waist circumference, and fat mass, this evidence is of low to moderate certainty. Future studies could investigate the effect of calcium supplementation on lean body mass to explore if there is a change in body composition.

Association between consumption of small fish and all-cause mortality among Japanese: the Japan Multi-Institutional Collaborative Cohort Study

OBJECTIVE

Although small fish are an important source of micronutrients, the relationship between their intake and mortality remains unclear. This study aimed to clarify the association between intake of small fish and all-cause and cause-specific mortality.

DESIGN

We used the data from a cohort study in Japan. The frequency of the intake of small fish was assessed using a validated FFQ. The hazard ratio (HR) and 95 % confidence interval (CI) for all-cause and cause-specific mortality according to the frequency of the intake of small fish by sex were estimated using a Cox proportional hazard model with adjustments for covariates.

SETTING

The Japan Multi-Institutional Collaborative Cohort Study.

PARTICIPANTS

A total of 80 802 participants (34 555 males and 46 247 females), aged 35-69 years.

RESULTS

During a mean follow-up of 9·0 years, we identified 2482 deaths including 1495 cancer-related deaths. The intake of small fish was statistically significantly and inversely associated with the risk of all-cause and cancer mortality in females. The multivariable-adjusted HR (95 % CI) in females for all-cause mortality according to the intake were 0·68 (0·55, 0·85) for intakes 1-3 times/month, 0·72 (0·57, 0·90) for 1-2 times/week and 0·69 (0·54, 0·88) for ≥ 3 times/week, compared with the rare intake. The corresponding HR (95 % CI) in females for cancer mortality were 0·72 (0·54, 0·96), 0·71 (0·53, 0·96) and 0·64 (0·46, 0·89), respectively. No statistically significant association was observed in males.

CONCLUSIONS

Intake of small fish may reduce the risk of all-cause and cancer mortality in Japanese females.

Glycated Walnut Meal Peptide-Calcium Chelates: Preparation, Characterization, and Stability

Finding stable and bioavailable calcium supplements is crucial for addressing calcium deficiency. In this study, glycated peptide-calcium chelates (WMPHs-COS-Ca) were prepared from walnut meal protein hydrolysates (WMPHs) and chitosan oligosaccharides (COSs) through the Maillard reaction, and the structural properties and stability of the WMPHs-COS-Ca were characterized. The results showed that WMPHs and COSs exhibited high binding affinities, with a glycation degree of 64.82%. After glycation, Asp, Lys, and Arg decreased by 2.07%, 0.46%, and 1.06%, respectively, which indicated that these three amino acids are involved in the Maillard reaction. In addition, compared with the WMPHs, the emulsifying ability and emulsion stability of the WMPHs-COS increased by 10.16 mg2/g and 52.73 min, respectively, suggesting that WMPHs-COS have better processing characteristics. After chelation with calcium ions, the calcium chelation rate of peptides with molecular weights less than 1 kDa was the highest (64.88%), and the optimized preparation conditions were 5:1 w/w for WMPH-COS/CaCl2s, with a temperature of 50 °C, a chelation time of 50 min, and a pH of 7.0. Scanning electron microscopy showed that the "bridging role" of WMPHs-COS changed to a loose structure. UV-vis spectroscopy and Fourier transform infrared spectrometry results indicated that the amino nitrogen atoms, carboxyl oxygen atoms, and carbon oxygen atoms in WMPHs-COS chelated with calcium ions, forming WMPHs-COS-Ca. Moreover, WMPHs-COS-Ca was relatively stable at high temperatures and under acidic and alkaline environmental and digestion conditions in the gastrointestinal tract, indicating that WMPHs-COS-Ca have a greater degree of bioavailability.

An Algorithm to Assess Calcium Bioavailability from Foods

BACKGROUND

The recommended calcium intakes to meet calcium requirements at various ages are based on average population absorption values. Absorption is altered by physiology, the calcium load, and type of food. The calcium intake necessary, therefore, to meet requirements depends upon diet composition, through bioavailability.

OBJECTIVE

The objectives of this study was to improve predictions of calcium bioavailability on the basis of the food matrix.

METHODS

We modeled calcium absorption data from individual foods, beverages, and fortified foods that were determined with calcium isotopic tracers and compared with milk as a referent to adjust for physiologic differences of the host.

RESULTS

Data from 496 observations were modeled to develop a predictive algorithm for calcium bioavailability in adults on the basis of calcium load and oxalate and phytate loads, which represent the 2 main inhibitors of calcium absorption.

CONCLUSIONS

This algorithm will be helpful in assessing calcium availability from the food supply, for developing diets for individuals and research cohorts, and for designing policies and interventions to address inadequate calcium intake for populations.

Effect of fortification with CaCO3 nanoparticles obtained from eggshell on the physical and sensory characteristics of three food matrices

Food fortification has attracted interest in recent years, due to the understanding that micronutrient deficiency is one of the causes of the global burden of disease, and that food fortification aims to prevent or correct a demonstrated deficiency of one or more nutrients in a specific population or population groups. Nutritional value is an important concern regarding fortification and new product development. However, people are not willing to sacrifice the organoleptic characteristics of food products. Therefore, the effect of CaCO3 nanoparticles (NPs-CaCO3) and commercial CaCO3 on the physical and sensory properties of three food matrices (cookies, fruit rolls and dairy desserts) was evaluated. A texture analysis was performed on cookies and fruit rolls; a viscosity analysis on dairy desserts; and a color analysis and sensory profile on the three matrices. The results showed that both types of calcium increase hardness in fortified biscuits and fruit rolls but, in the latter case, commercial calcium caused a higher increase in hardness (p < 0.05). Viscosity was higher in the desserts with NPs. Color presented significant changes in all the fortified matrices. These findings demonstrated that Ca-NPs are a good strategy for food fortification compared to commercial calcium carbonate, as fortification with high levels of calcium is a challenge for the food industry due to its effects on the product. The results showed that, in the matrices with commercial calcium, the changes were more evident, while the matrices fortified with Ca-NP have a better sensory response than commercial Ca, with a higher level of acceptance by the judges. Therefore Ca-NPs can be considered to be a good source of calcium for food product fortification that causes a slight effect on physical and sensory properties.

Pre-eclampsia in low and middle-income settings: What are the barriers to improving perinatal outcomes and evidence-based recommendations?

OBJECTIVE

To discuss the points that still challenge low- and middle-income countries (LMICs) and strategies that have been studied to help them overcome these issues.

METHODS

Narrative review addressing 20 years of articles concerning pre-eclampsia morbidity and mortality in LMICs. We summarized evidence-based strategies to overcome the challenges in order to reduce the pre-eclampsia impact on perinatal outcomes.

RESULTS

Pre-eclampsia is the first or second leading cause in the ranking of avoidable causes of maternal death, and approximately 16% of all maternal deaths are attributable to eclampsia and pre-eclampsia. Considering the social and economic contexts, it represents a major public health concern, and prevention and early detection of pre-eclampsia seem to be a major challenge. Reducing maternal mortality related to hypertensive disturbances depends on public policies to manage these preventable conditions. Early and continuous recognition of signs of severity related to hypertensive disorders during pregnancy and childbirth, self-monitoring of symptoms and blood pressure, as well as preventive approaches such as aspirin and calcium, and magnesium sulfate, are lifesaving procedures that have not yet reached a universal scale.

CONCLUSION

This review provides a vision of relevant points to support pregnant women in overcoming the constraints to healthcare access in LMICs, and strategies that can be applied in primary prenatal care units.

Bibliometric analysis of water kefir and milk kefir in probiotic foods from 2013 to 2022: A critical review of recent applications and prospects

Although milk kefir and water kefir have different physical, chemical and microbiological characteristics, several microbial species that make up kefir stand out with probiotic functions. Furthermore, because it is suitable for a variety of substrates, kefir and the species of probiotic microorganisms that make it up are seen as a promising alternative in the development of probiotic and health-promoting foods. The aim of this study was to carry out a bibliometric analysis of water kefir and milk kefir in probiotic foods and to critically analyze recent applications and prospects. Using the Scopus database, 202 documents published between 2013 and 2022 were identified and submitted to bibliometric analysis using the VOSviewer software. Regarding recent applications, 107 documents published between 2021 and June 2023 were identified. It was observed that, in the literature consulted, no study used bibliometric analysis to evaluate the use of water kefir and milk kefir in probiotic foods. Due to the presence of probiotic species, kefir has been listed as an alternative for the production of new probiotic food matrices that are beneficial to health. Recent applications show kefir's potential in the development of probiotic products based on fruit and fruit juice, whey beverages, fermented milks and derivatives, and alcoholic beverages such as beers.

Vegan diet: nutritional components, implementation, and effects on adults' health

Vegan diet has emerged as a popular dietary choice for people worldwide in recent times, due to concerns such as health issues, animal rights and welfare, and the sustainability of the environment. The purpose of this literature review was to explain how a vegan diet may affect the health of adults and to point out beneficial components found in it as well as any difficulties associated with its implementation. Evidence supports that a vegan diet can reduce the risk of chronic diseases, such as type 2 diabetes, hypertension, and certain types of cancer. A well-planned vegan diet must include adequate calories and nutrients, as well as the necessary supplements, such as vitamin B12, vitamin D and EPA/DHA. Given the current growing interest in plant-based diets among the general population, it is crucial to understand both the barriers, risks, and benefits of the vegan diet among physicians, policy makers, and the general population.

Calcium food sources in primary school children with low calcium intakes in Kuala Lumpur

Background: Adequate calcium intake at an early age is crucial to achieving peak bone mass. Nevertheless, low calcium intake is common in Malaysian children. Aim: This study examined the calcium food sources and factors associated with low calcium intake among 243 children aged 9-11 years in Kuala Lumpur. Methods: Diet histories and bone density were measured. Results: The mean calcium intake was 370 ± 187 mg/day. The main contributors to calcium intake were beverages (19.2%), cereal (18.6%), milk and dairy (13.0%), meat and poultry (12.9%), and fish and seafood (10.1%). Within each food group, calcium-contributing foods tend to be from low bioavailability sources such as rice, cocoa-based and malted drinks, and chicken rather than milk. Children who practised regular meals, ate breakfast and snacks and consumed milk more than one serving daily have a higher calcium intake. Conclusion: In conclusion, public health strategies to improve the status of low calcium intake and poor choices of calcium-rich foods are needed to optimise bone health in this population.

Locally relevant food-based recommendations could increase iron and calcium intake for adolescent girls in Vietnam

Unhealthy eating habits are common among adolescents in Vietnam, where transitioning food environments increasingly offer energy-dense micronutrient-poor foods. Successful behavior change approaches must be feasible and acceptable, promoting local foods that are available, accessible, and preferred. Yet, few studies have investigated the potential of food-based approaches for adolescents. We used linear programming to identify problem nutrients, local nutrient sources, and realistic food-based recommendations (FBRs) to improve nutrient intake among girls 16-22 years in Thai Nguyen, Vietnam. We then identified a reduced set of FBRs to prioritize the most critical micronutrient gaps. Calcium and iron targets could not be met in any realistic diet modeling scenario. The best set of FBRs included seven recommendations which could meet intake targets for 9 of 11 modeled micronutrients. The best reduced set of three FBRs targeting iron and calcium only-although more feasible for behavior change-was less effective at improving intake of these nutrients since fewer foods were recommended. Given the difficulty of meeting calcium and iron targets using local foods within acceptable dietary patterns, additional interventions, such as supplementation, staple food fortification, or increasing the availability of affordable calcium- and iron-rich foods, may be necessary to promote dietary adequacy for adolescent girls.

A comprehensive review on the impact of calcium and vitamin D insufficiency and allied metabolic disorders in females

Calcium is imperative in maintaining a quality life, particularly during later ages. Its deficiency results in a wide range of metabolic disorders such as dental changes, cataracts, alterations in brain function, and osteoporosis. These deficiencies are more pronounced in females due to increased calcium turnover throughout their life cycle, especially during pregnancy and lactation. Vitamin D perform a central role in the metabolism of calcium. Recent scientific interventions have linked calcium with an array of metabolic disorders in females including hypertension, obesity, premenstrual dysphoric disorder, polycystic ovary syndrome (PCOS), multiple sclerosis, and breast cancer. This review encompasses these female metabolic disorders with special reference to calcium and vitamin D deficiency. This review article aims to present and elaborate on available data regarding the worldwide occurrence of insufficient calcium consumption in females and allied health risks, to provide a basis for formulating strategies and population-level scientific studies to adequately boost calcium intake and position where required.

Including calcium-fortified water or flour in modeled diets based on local foods could improve calcium intake for women, adolescent girls, and young children in Bangladesh, Uganda, and Guatemala

Adequate calcium intake is essential for health, especially for infants, children, adolescents, and women, yet is difficult to achieve with local foods in many low- and middle-income countries. Previous analysis found it was not always possible to identify food-based recommendations (FBRs) that reached the calcium population recommended intake (PRI) for these groups in Bangladesh, Guatemala, and Uganda. We have modeled the potential contribution of calcium-fortified drinking water or wheat flour to FBR sets, to fill the remaining intake gaps. Optimized diets containing fortified products, with calcium-rich local foods, achieved the calcium PRI for all target groups. Combining fortified water or flour with FBRs met dietary intake targets for adolescent girls in all geographies and allowed a reduction from 3-4 to the more feasible 1-2 FBRs. Water with a calcium concentration of 100 mg/L with FBRs was sufficient to meet calcium targets in Uganda, but higher concentrations (400-500 mg/L) were mostly required in Guatemala and Bangladesh. Combining calcium-fortified wheat flour at 400 mg/100 g of flour and the FBR for small fish resulted in diets meeting the calcium PRI in Bangladesh. Calcium-fortified water or flour could improve calcium intake for vulnerable populations, especially when combined with FBRs based on locally available foods.

Exploring the Potential Benefits of Natural Calcium-Rich Mineral Waters for Health and Wellness: A Systematic Review

This systematic review investigates the potential health and wellness benefits of natural calcium-rich mineral waters. It emphasizes the importance of dietary calcium sourced from natural mineral waters in promoting bone health, maintaining cardiovascular function, aiding in weight management, and enhancing overall well-being. The review process involved the comprehensive analysis of peer-reviewed articles, clinical trials, and experimental studies published within the last decade. Findings reveal that consuming calcium-rich mineral water can contribute significantly to daily calcium intake, particularly for those with lactose intolerance or individuals adhering to plant-based diets. The unique bioavailability of calcium from such waters also appears to enhance absorption, thus potentially offering an advantage over other calcium sources. The potential benefits extend to the cardiovascular system, with some studies indicating a reduction in blood pressure and the prevalence of cardiovascular diseases. Emerging evidence suggests that calcium-rich mineral water might have a role in body weight management, though further research is needed. The review identifies several areas requiring additional research, such as the potential interaction between calcium-rich mineral water and other dietary components, the effects on populations with specific health conditions, and the long-term effects of consumption. In conclusion, natural calcium-rich mineral waters show promise as a readily accessible and bioavailable sources of dietary calcium, potentially beneficial for a broad range of individuals. However, further investigation is required to fully understand its range of health impacts and define optimal intake levels.

Could local foods achieve recommended calcium intakes for nutritionally vulnerable populations in Uganda, Guatemala, and Bangladesh?

Globally, dietary intake of calcium is often insufficient, and it is unclear if adequacy could be achieved by promoting calcium-rich local foods. This study used linear programming and household consumption data from Uganda, Bangladesh, and Guatemala to assess whether local foods could meet calcium population reference intakes (Ca PRIs). The most promising food-based approaches to promote dietary calcium adequacy were identified for 12- to 23-month-old breastfed children, 4- to 6-year-old children, 10- to 14-year-old girls, and nonpregnant and nonbreastfeeding (NPNB) women of reproductive age living in two regions of each country. Calcium-optimized diets achieved 75-253% of the Ca PRI, depending on the population, and were <100% for 4- to 6-year-olds in one region of each country and 10- to 14-year-old girls in Sylhet, Bangladesh. The best food sources of calcium were green leafy vegetables and milk, across geographic locations, and species of small fish, nixtamalized (lime-treated) maize products, sesame seeds, and bean varieties, where consumed. Food-based recommendations (FBRs) achieving the minimum calcium threshold were identified for 12- to 23-month-olds and NPNB women across geographic locations, and for 4- to 6-year-olds and 10-to 14-year-old girls in Uganda. However, for 4- to 6-year-olds and 10- to 14-year-old girls in Bangladesh and Guatemala, calcium-adequate FBRs could not be identified, indicating a need for alternative calcium sources or increased access to and consumption of local calcium-rich foods.

Calcium status assessment at the population level: Candidate approaches and challenges

Inadequate dietary calcium intake is a global public health problem that disproportionately affects low- and middle-income countries. However, the calcium status of a population is challenging to measure, and there are no standard methods to identify high-risk communities even in settings with an elevated prevalence of a disease caused or exacerbated by low calcium intake (e.g., rickets). The calcium status of a population depends on numerous factors, including intake of calcium-rich foods; the bioavailability of the types of calcium consumed in foods and supplements; and population characteristics, including age, sex, vitamin D status, and genetic attributes that influence calcium retention and absorption. The aim of this narrative review was to assess candidate indicators of population-level calcium status based on a range of biomarkers and measurement methods, including dietary assessment, calcium balance studies, hormonal factors related to calcium, and health outcomes associated with low calcium status. Several promising approaches were identified, but there was insufficient evidence of the suitability of any single indicator to assess population calcium status. Further research is required to develop and validate specific indicators of calcium status that could be derived from the analysis of data or samples that are feasibly collected in population-based surveys.

Dietary and Nutrient Intake, Eating Habits, and ItsAssociation with Maternal Gestational Weight Gain and Offspring’s Birth Weight in Pregnant Adolescents

Pregnant adolescents’ diet and eating habits are inadequate; however, their association with gestational weight gain (GWG) is uncertain. We aimed to analyze whether there is an association between dietary and nutrient intake and eating habits with GWG among pregnant adolescents and their offspring’s birth weight. A longitudinal study was performed with 530 participants. We assessed GWG and applied several tools, such as a food frequency questionnaire and 24-h recall, to obtain dietary and nutrient intake and eating habits. The birth weight of adolescents’ offspring was registered. Later, we performed crude and adjusted Poisson models. The mean age was 15.8 ± 1.3 years. Of all food groups, the lowest frequency of adequate intake corresponded to vegetables (7%) and legumes (10.2%). Excessive (36.8%) and insufficient (40.9%) GWG were observed. Pregnant adolescents with inadequate legumes intake increased the probability of excessive GWG: (PR 1.86 95% CI 1.00–3.44). Cereals and grains were positively associated with GWG: (PR 1.65, 95% CI 1.18–2.29). Energy, macronutrient intake, and eating habits were not associated with GWG. Offspring’s small gestational age (SGA) increased when pregnant adolescents had inadequate sugar-sweetened beverages intake: PR (1.58, 95% CI 1.01–2.49) and when pregnant adolescent watched television (TV). In our sample of Mexican adolescents, dietary and nutrient intake and eating habits were inadequate. Excessive dietary intake from cereals, grains, and animal-sourced foods along with insufficient legumes were associated with excessive GWG. Watching TV while adolescents ate was associated with the birth weight of the offspring.

Calcium deficiency worldwide: prevalence of inadequate intakes and associated health outcomes

Dietary calcium deficiency is considered to be widespread globally, with published estimates suggesting that approximately half of the world's population has inadequate access to dietary calcium. Calcium is essential for bone health, but inadequate intakes have also been linked to other health outcomes, including pregnancy complications, cancers, and cardiovascular disease. Populations in low- and middle-income countries (LMICs) are at greatest risk of low calcium intakes, although many individuals in high-income countries (HICs) also do not meet recommendations. Paradoxically, many LMICs with lower calcium intakes show lower rates of osteoporotic fracture as compared with HICs, though data are sparse. Calcium intake recommendations vary across agencies and may need to be customized based on other dietary factors, health-related behaviors, or the risk of calcium-related health outcomes. The lack of standard methods to assess the calcium status of an individual or population has challenged efforts to estimate the prevalence of calcium deficiency and the global burden of related adverse health consequences. This paper aims to consolidate available evidence related to the global prevalence of inadequate calcium intakes and associated health outcomes, with the goal of providing a foundation for developing policies and population-level interventions to safely improve calcium intake and status where necessary.