Prospective associations between total, animal, and vegetable calcium intake and metabolic syndrome in adults aged 40 years and older

Dietary calcium intake in relation to metabolic syndrome in adults: A systematic review and dose-response meta-analysis of epidemiological studies with GRADE assessment

Numerous studies have examined the relationship of calcium intake and metabolic syndrome (MetS) in adults in previous decades; but the results were inconsistent across different societies. This systematic review and dose-response meta-analysis assessed the relation between calcium consumption and MetS in adults. We did a systematic search of all articles published up to July 2023 in Scopus, PubMed/Medline, ISI Web of Science electronic databases, and Google Scholar. Observational studies investigated the association between dietary calcium (Ca) intake and MetS in adults were eligible to be included. For computing the estimates, a random effects model was applied. Combining 24 effect size from 17 investigations (15 cross-sectional and two cohort studies) with 74,720 participants and 18,200 cases showed that highest versus lowest level of dietary Ca intake was related to 23% significant decreased odds of MetS (OR = 0.77; 95% CI: 0.66, 0.89). Linear dose-response analysis of estimates from 12 investigations showed that each 100 mg/day increment in dietary Ca intake was associated with 3% marginally significant decreased odds in MetS (OR = 0.97; 95%CI: 0.93, 1.01). In nonlinear dose-response analysis of 12 studies with 67,896 participants, a significant association between dietary calcium intake and MetS was found (Pnonlinearity <0.001); such that 500 mg/day dietary calcium intake was related to maximum decrease in odds of MetS. According to this meta-analysis, the likelihood of MetS was significantly lower in adults with higher level of dietary calcium intake. Further large-scale prospective cohort investigations are needed to obtain stronger and more accurate results.

Association between calcium intake from different food sources during childhood and cardiometabolic risk on adolescence: The Generation XXI birth cohort

BACKGROUND

Calcium intake has been associated with lower adiposity, but few studies explored the longitudinal relation of calcium from different sources and cardiometabolic markers in young population.

OBJECTIVE

Prospectively estimate the association between dairy and non-dairy calcium intake at 4, 7, and 10 years (y) of age and cardiometabolic risk at 13 y.

METHODS

The sample included 4017 participants from the Generation XXI birth cohort. Dietary data were collected from a 3-day food diary. Cardiometabolic clusters at 13 y were estimated by a probabilistic Gaussian mixture model (z-score of waist circumference [WC], HOMA-IR; HDL cholesterol, triglycerides, and systolic blood pressure [BP]). Multivariable linear and logistic regression models were used to estimate associations.

RESULTS

Calcium intake (/100 mg), after adjustment for confounders, was negatively and significantly associated with body mass index (BMI) (β = -0.02, 95% CI: -0.04; -0.01), WC (cm) (β = -0.23, 95% CI: -0.36; -0.11), and diastolic BP (mmHg) (β = -0.14, 95% CI: -0.26; -0.03). After additional adjustment for total energy intake, associations lose statistical significance. Calcium intake from milk at 7 y was inversely associated with WC (β = -0.25, 95% CI: -0.48; -0.03) and from yogurt at 10 y was associated with higher BMI (β = 0.08, 95% CI: 0.03; 0.13) and WC (β = 0.54, 95% CI: 0.12; 0.96). Calcium from vegetables at 4, 7, 10 y reduces later cardiometabolic risk (OR = 0.71; OR = 0.84; OR = 0.98, respectively).

CONCLUSIONS

This study supports a protective effect of calcium on adolescents' cardiometabolic health, especially from vegetables.

Calcium- and Sodium-Rich Food Intake among Koreans with and without Metabolic Syndrome: Cross-Sectional Analysis of the Korean Genome and Epidemiology Study

BACKGROUND

The prevalence of metabolic syndrome (MetS) is increasing. While calcium and sodium are known nutritional factors used for managing MetS, few studies have focused on food-based analyses. This cross-sectional study examined the distribution of calcium- and sodium-rich food intake among Koreans with MetS.

METHODS

This cross-sectional analysis evaluated 130,423 participants from the Health Examinees-Gem cohort study. Foods contributing up to 90% of the calcium and sodium intake were selected from the semi-quantitative food frequency questionnaire, and consumption levels were calculated. MetS was defined as satisfying three or more criteria from the National Cholesterol Education Program Adult Treatment Panel III. The results are presented as odds ratios (OR) with an interquartile range (ORIQR) and 95% confidence interval.

RESULTS

Participants with MetS showed a low calcium intake (ORIQR = 0.95 and 0.92 for men and women, respectively), low consumption of dairy products (ORIQR = 0.92 and 0.89), beverages except for coffee or green tea (ORIQR = 0.97 and 0.96), and bread (ORIQR = 0.96 and 0.94). Men with MetS consumed high total sodium (ORIQR = 1.04), and large amounts of Kimchi (ORIQR = 1.03), fermented paste (ORIQR = 1.04), and noodles (ORIQR = 1.07). Women with MetS consumed more Kimchi than those without MetS (ORIQR = 1.04). The odds ratio for the low calcium and high sodium group compared to the high calcium and low sodium group was 1.26.

CONCLUSION

The MetS group consumed less calcium-rich foods and more sodium-rich foods than those without MetS. Patients with MetS might benefit from precise recommendations of high calcium-rich and low sodium-rich foods.

National trends in nine key minerals intake (quantity and source) among U.S. adults, 1999 to march 2020

BACKGROUND

Changes in economy and dietary guidelines brought a great shock to diet quality and meal behaviors, but if these transformations have extended to minerals intake and their sources was still poorly understood. It is essential to evaluate time trends in minerals intake and their sources to inform policy makers.

OBJECTIVE

To investigate trends in minerals intake and their sources among U.S. adults.

METHODS

This analysis used dietary data collected by 24-h recalls from U.S. adults (≥ 20 years) in NHANES (1999-March 2020). Minerals intake, age-adjusted percentage of participants meeting recommendations, and minerals sources were calculated among all participants and by population subgroups in each NHANES survey cycle. Weighted linear or logistic regression models were used to examine the statistical significance of time trends.

RESULTS

A total of 48223 U.S. adults were included in this analysis. From 1999 to March 2020, intake of calcium (from 0.94 to 1.02 g/day), magnesium (from 308.07 to 321.85 mg/day), phosphorus (from 1.24 to 1.30 g/day), and sodium (from 3.24 to 3.26 mg/day) from food and beverages (FB) and dietary supplements (DSs) significantly increased, and intake of iron (from 19.17 to 16.38 mg/day), zinc (from 16.45 to 14.19 mg/day), copper (from 1.79 to 1.38 mg/day), and potassium (from 2.65 to 2.50 g/day) from FB + DSs decreased (all FDR < 0.05). Additionally, age-adjusted percentage of participants meeting recommendations for calcium, phosphorus, sodium, and selenium significantly increased, that for iron, potassium, zinc, and copper decreased (all FDR < 0.05). Minerals intake and time trends in minerals intake were highly variable depending on age, gender, race/ethnicity, education, and income. For example, white, higher socioeconomic status participants had a higher minerals intake (e.g. iron, zinc, and copper), but had a greater decrease in minerals intake. Furthermore, the percentage of minerals from milks and DSs decreased, and that from beverages increased.

CONCLUSION

From 1999 to March 2020, both minerals intake and their sources experienced a significant alteration among U.S. adults. Many differences in minerals intake and their food sources across sociodemographic characteristics appeared to narrow over time. Although some improvements were observed, important challenges, such as overconsumption of sodium and underconsumption of potassium, calcium, and magnesium, still remained among U.S. adults.

Dietary calcium is inversely associated with hepatitis B virus infection: an analysis of US National Health and Nutrition Examination Survey (NHANES) 2007-2020

BACKGROUND

There have been studies on the relationship between hepatitis B virus (HBV) infection and diet. We hypothesized HBV infection is related to dietary calcium intake, but the evidence is limited. This study aimed to examine whether dietary calcium intake is independently related to HBV infection in the United States population.

METHODS

A total of 20,488 participants aged over 20 years from the National Health and Nutrition Examination Survey (NHANES), conducted from 2007 to 2020, were included in this study. Pearson correlation was used to test the association between dietary calcium and serum calcium. The relationships of HBV infection with dietary calcium and serum calcium were assessed by logistic regression models.

RESULTS

There was a weak correlation between dietary calcium and serum calcium (r = 0.048). Logistic regression models indicated that HBV infection had a linear negative correlation with dietary calcium (OR 0.37; 95%CI 0.19, 0.76). For each additional 10 mg dietary calcium, the possibility of HBV infection was reduced by 63%. Hepatitis B positive participants had lower serum calcium content than negative participants. Stratified analysis shown the linear relationship between calcium and HBV infection varied among sex, race/ethnicity, and body mass index.

CONCLUSION

Our findings demonstrated HBV infection was linearly and inversely correlated with dietary calcium. The current study is expected to offer a fresh perspective on reducing HBV infection.

Association between long working hours and unmet dental needs in wage workers

BACKGROUND

Many previous studies on the reasons behind unmet dental needs focus on economic issues. However, in this research, we aimed to investigate the relationship between long working hours and unmet dental needs while considering the influence of occupational factors in wage workers.

METHODS

This study used data from the Korea National Health and Nutrition Examination Survey (2012-2018) and analyzed a sample of 12,104 wage workers. Unmet dental needs were defined as cases in which individuals did not receive dental care, despite their need for examination or treatment, within the last year. Long working hours were defined as exceeding 52 h per week, based on the standard working hours stipulated by the Labor Standards Act. A binomial model was applied to calculate the prevalence ratio through multivariate logistic regression analysis.

RESULTS

The prevalence of unmet dental needs was observed in 3,948 cases (32.5%), among which 1,478 attributed their presence to lack of time. The prevalence of unmet dental needs showed an inverse relationship with the education level and household income. The wage workers who worked long hours had the highest prevalence of unmet dental needs. Long working hours were found to be 1.18 times (95% CI 1.07-1.29) more likely to result in unmet dental care compared to working less than 40 h. The relationship between long working hours and unmet dental needs were statistically significant only in men (PR 1.24, 95% CI 1.07-1.43). However, the relationship between long working hours and unmet dental needs owing to time were in both men and women (men: PR 1.59, 95% CI 1.20-2.11, women: PR 1.90, 95% CI 1.48-2.43).

CONCLUSIONS

This study confirmed that long working hours and unmet dental needs are related when occupational factors are taken into consideration, despite the absence of oral health indicators. Using this study as a reference, further research is necessary to identify the underlying causes of unmet dental care and to improve access to dental services in the future.

Dietary macrominerals: Updated review of their role and orchestration in human nutrition throughout the life cycle with sex differences

Macrominerals play vital roles in a multitude of physiologic systems. A myriad of biochemical reactions are dependent on or affected by these electrolytes. The current review attempts to identify the role of macrominerals as calcium, phosphorus, magnesium, sodium, potassium and sulfur in human health, in addition to their absorption and homeostasis inside the body. We also focused on their amount in major food sources and the recommended daily intake of each macromineral. In addition, a deep insight into the orchestration of the 6 different macrominerals' requirements is presented across the human life cycle, beginning from fertility and pregnancy, and reaching adulthood and senility, with insight on interactions among them and underlying action mechanisms. The effect of sex is also presented for each mineral at each life stage to highlight the different daily requirements and/ or effects. The current review identified the role of macrominerals in human health, in addition to their absorption and homeostasis in the body. Based on the in-depth understanding of the factors influencing the metabolism of macrominerals, we could better explore their safety and possible therapeutic potential in specific disorders. There is still a need to precisely demonstrate the bioavailability of macrominerals from various types of functional food.

Dietary calcium intake in relation to blood lipids and lipoproteins profiles: A systematic review and meta-analysis of epidemiologic studies

AIMS

Findings of prior investigations on the association between calcium intake and lipid profiles were inconsistent. We performed a systematic review and meta-analysis on epidemiologic studies to evaluate the relationship of dietary calcium intake with blood lipids and lipoproteins.

DATA SYNTHESIS

A systematic search up to April 2021 was performed in different electronic databases, including MEDLINE (PubMed), Scopus, Web of Science (ISI), and Google Scholar for epidemiological studies that considered dietary calcium intake as the exposure and reported risk of dyslipidemia or blood lipids and lipoproteins concentrations (as mean ± SD or mean ± SE or median (Inter Quartile Range) as the outcomes of interest in adult populations from both genders (18 years or older), regardless of their health status. Nineteen cross-sectional studies were included in the analysis. Combining estimates from 11 studies (including 33,304 subjects) revealed that individuals in the highest category of calcium intake, compared to the lowest one, had 5.94 mg/dL lower circulating triglyceride (TG) concentration (weighted mean difference (WMD): -5.94; 95% CI: -8.27, -3.62), 4.02 mg/dL lower circulating low-density lipoprotein cholesterol (LDL-c) levels (WMD: -4.02; 95% CI: -7.08, -0.95), and 1.56 mg/dL higher blood high-density lipoprotein cholesterol (HDL-c) (WMD: 1.56; 95% CI: 0.81, 2.30). Although meta-analysis on 13 studies (including 38,714 participants) did not reveal a significant relationship between dietary calcium intake and odds of dyslipidemia or hyperlipidemia in the whole population, the highest vs. lowest level of calcium intake was related to 42% decreased odds of low blood HDL-c levels in females (95% CI: 0.40, 0.84) and 41% increased odds in males (95% CI: 1.21, 1.65).

CONCLUSIONS

This meta-analysis demonstrated that individuals with the highest dietary calcium intake might have lower blood TG, LDL-c, and higher HDL-c concentrations as compared to those with the lowest calcium intake. However, the linkage between dietary calcium intake with odds of hyperlipidemia or dyslipidemia was not significant. Because of the cross-sectional nature of included studies, causality could not be proven. Further prospective studies are needed to affirm these findings.

Dietary calcium intake in relation to type-2 diabetes and hyperglycemia in adults: A systematic review and dose-response meta-analysis of epidemiologic studies

Several epidemiological studies investigated the relation of Ca intake with type 2 diabetes mellitus (T2DM), but there were inconsistencies in their findings. So, we conducted a systematic review and dose-response meta-analysis to quantify the relation of dietary Ca intake with the risk of T2DM/hyperglycemia in adults. A systematic search was conducted up to May 2021, in MEDLINE (Pubmed), Web of Science (WOS), Scopus electronic databases and Google Scholar, for epidemiological studies that investigated the relation of dietary Ca intake (as the exposure) and T2DM/hyperglycemia (as the outcome) in adults, without restriction in publication date and language. Finally, 8 cohort and 9 cross-sectional studies were included in the analysis. The body of evidence was assessed by the GRADE approach. Combining effect sizes from prospective cohort studies included 255,744 general adult population illustrated that highest level of dietary Ca intake, compared to lowest category, was related to an 18% reduced risk of T2DM (RR: 0.82; 95% CI 0.74-0.92). Based on linear dose-response analysis (including 255,744 healthy individuals and 13,531 patients with T2DM), each 300, 600 and 1000 mg/day increment in dietary Ca intake was respectively associated to 7, 14 and 23% reduced risk of T2DM. There was a steeper reduction in risk of T2DM when dietary Ca intake increased from low levels to 750 mg/day. Nevertheless, meta-analysis of cross-sectional studies revealed an inverse significant association between dietary Ca intake and T2DM/hyperglycemia only in the female population (OR: 0.66; 95% CI 0.50-0.88). This meta-analysis illustrated an inverse association between dietary Ca intake and risk of T2DM in general adult populations in prospective cohort studies, in a dose-response manner. It seems that increasing dietary Ca intake from low levels to around 750 mg/day was inversely related to risk of T2DM. In cross-sectional studies, an inverse relation between dietary Ca intake and T2DM/hyperglycemia was found only in females.