Last update
5/3/2026
Reviewed By
Reviewed By
Overview
SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.1
USERS' SCORE
Moderately Good
Based on 28 Reviews
7.6
Supplement Facts
Serving Size: 1 Veg Capsule
Amount Per Serving
%DV
Calcium (from Fossilized Coral Calcium)
350 mg
27%
Fossilized Coral Calcium
1 g (1,000 mg)
†
Top Medical Research Studies
8
We explored the effect of coral calcium and zeolite on bone health in mice, particularly focusing on postmenopausal bone loss caused by ovariectomy. After six months of supplementation, we observed that these treatments helped restore bone mass in the distal femur and improved bone structure.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
Read More
9
Our research explored the effects of a new calcium-loaded complex, made from Antarctic krill protein and enriched with pectin, on calcium absorption and bone health in mice with calcium deficiency. We created a model that simulated calcium deficiency, which is a significant concern as it can contribute to osteoporosis.
We observed that chronic calcium deprivation led to decreased calcium absorption and deterioration of bone structure. However, the P + Ca + HMP complex significantly improved calcium retention and increased the strength of the femur, indicating a positive impact on bone health.
Additionally, this complex improved the structure of the trabecular network, which is essential for maintaining strong bones. The presence of beneficial bacteria in the gut also rose after the intervention, and these were linked to better calcium absorption and bone synthesis. Overall, these findings point to the potential of the P + Ca + HMP complex as an effective calcium supplement that could help prevent calcium deficiency and thus support bone health.
We observed that chronic calcium deprivation led to decreased calcium absorption and deterioration of bone structure. However, the P + Ca + HMP complex significantly improved calcium retention and increased the strength of the femur, indicating a positive impact on bone health.
Additionally, this complex improved the structure of the trabecular network, which is essential for maintaining strong bones. The presence of beneficial bacteria in the gut also rose after the intervention, and these were linked to better calcium absorption and bone synthesis. Overall, these findings point to the potential of the P + Ca + HMP complex as an effective calcium supplement that could help prevent calcium deficiency and thus support bone health.
Read More
8
Calcium's role in osteoporosis explored
We sought to understand whether individuals with affective disorders (AD) receive different levels of osteoporosis treatment compared to those without these mental health conditions. To do this, we analyzed a large group of people over a ten-year period, looking at how often patients with AD received calcium prescriptions and referrals for osteoporosis screening.
Our findings show that people with AD were more likely to receive calcium treatments, including calcium alone and calcium combined with vitamin D, compared to healthy controls. Specifically, the study highlighted that individuals with AD had a 64% higher chance of receiving a calcium prescription and a 125% higher likelihood of being referred for screening within two years of their diagnosis.
Despite these increased rates of screening and treatment, there remains a question about whether such efforts are effectively reducing the risk of osteoporosis and fractures in this vulnerable group. Factors such as age, sex, ethnic background, and use of analgesics also played significant roles in the treatment pathways for these patients, indicating that while there are advancements in management, the overall effectiveness still requires further investigation.
Our findings show that people with AD were more likely to receive calcium treatments, including calcium alone and calcium combined with vitamin D, compared to healthy controls. Specifically, the study highlighted that individuals with AD had a 64% higher chance of receiving a calcium prescription and a 125% higher likelihood of being referred for screening within two years of their diagnosis.
Despite these increased rates of screening and treatment, there remains a question about whether such efforts are effectively reducing the risk of osteoporosis and fractures in this vulnerable group. Factors such as age, sex, ethnic background, and use of analgesics also played significant roles in the treatment pathways for these patients, indicating that while there are advancements in management, the overall effectiveness still requires further investigation.
Read More
Most Useful Reviews
9
Effective for prevention
1 people found this helpful
The ingredients are natural and effectively support osteoporosis prevention in the elderly. I consume it daily and recommend it highly.
Read More
10
High-quality calcium
This NOW Foods Coral Calcium is a top-notch product, perfect for those wanting to maintain bone health. It uses natural coral minerals for better absorption, effectively supplying the necessary calcium to prevent osteoporosis and improve overall bone and dental health. I wholeheartedly recommend this high-quality supplement.
Read More
9
Osteoporosis benefits
Excellent for patients with osteoporosis. It has great bioavailability and benefits.
Read More
Medical Researches
SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.1
- All Researches
9
Our research explored the effects of a new calcium-loaded complex, made from Antarctic krill protein and enriched with pectin, on calcium absorption and bone health in mice with calcium deficiency. We created a model that simulated calcium deficiency, which is a significant concern as it can contribute to osteoporosis.
We observed that chronic calcium deprivation led to decreased calcium absorption and deterioration of bone structure. However, the P + Ca + HMP complex significantly improved calcium retention and increased the strength of the femur, indicating a positive impact on bone health.
Additionally, this complex improved the structure of the trabecular network, which is essential for maintaining strong bones. The presence of beneficial bacteria in the gut also rose after the intervention, and these were linked to better calcium absorption and bone synthesis. Overall, these findings point to the potential of the P + Ca + HMP complex as an effective calcium supplement that could help prevent calcium deficiency and thus support bone health.
We observed that chronic calcium deprivation led to decreased calcium absorption and deterioration of bone structure. However, the P + Ca + HMP complex significantly improved calcium retention and increased the strength of the femur, indicating a positive impact on bone health.
Additionally, this complex improved the structure of the trabecular network, which is essential for maintaining strong bones. The presence of beneficial bacteria in the gut also rose after the intervention, and these were linked to better calcium absorption and bone synthesis. Overall, these findings point to the potential of the P + Ca + HMP complex as an effective calcium supplement that could help prevent calcium deficiency and thus support bone health.
Read More
9
We explored how salmon calcitonin (sCT) works in tandem with calcium antagonists—specifically verapamil, nifedipine, and diltiazem—to influence blood calcium and phosphorus levels in female rats with osteoporosis post-ovarian removal.
The study involved a systematic approach where we administered these combinations to different groups of osteoporotic rats and measured their blood levels. Our findings revealed that combining sCT with nifedipine had a particularly strong effect in lowering both calcium and phosphorus in the blood, outperforming the use of sCT alone.
Our analysis indicated that while sCT with nifedipine was most effective, the combinations with verapamil and diltiazem also showed beneficial effects, albeit to a lesser extent. These insights provide valuable information on how combination therapies might be targeted for treating postmenopausal osteoporosis, potentially paving the way for more effective treatment options in human patients.
The study involved a systematic approach where we administered these combinations to different groups of osteoporotic rats and measured their blood levels. Our findings revealed that combining sCT with nifedipine had a particularly strong effect in lowering both calcium and phosphorus in the blood, outperforming the use of sCT alone.
Our analysis indicated that while sCT with nifedipine was most effective, the combinations with verapamil and diltiazem also showed beneficial effects, albeit to a lesser extent. These insights provide valuable information on how combination therapies might be targeted for treating postmenopausal osteoporosis, potentially paving the way for more effective treatment options in human patients.
Read More
8
We explored the effect of coral calcium and zeolite on bone health in mice, particularly focusing on postmenopausal bone loss caused by ovariectomy. After six months of supplementation, we observed that these treatments helped restore bone mass in the distal femur and improved bone structure.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
Read More
8
Calcium's role in osteoporosis explored
We sought to understand whether individuals with affective disorders (AD) receive different levels of osteoporosis treatment compared to those without these mental health conditions. To do this, we analyzed a large group of people over a ten-year period, looking at how often patients with AD received calcium prescriptions and referrals for osteoporosis screening.
Our findings show that people with AD were more likely to receive calcium treatments, including calcium alone and calcium combined with vitamin D, compared to healthy controls. Specifically, the study highlighted that individuals with AD had a 64% higher chance of receiving a calcium prescription and a 125% higher likelihood of being referred for screening within two years of their diagnosis.
Despite these increased rates of screening and treatment, there remains a question about whether such efforts are effectively reducing the risk of osteoporosis and fractures in this vulnerable group. Factors such as age, sex, ethnic background, and use of analgesics also played significant roles in the treatment pathways for these patients, indicating that while there are advancements in management, the overall effectiveness still requires further investigation.
Our findings show that people with AD were more likely to receive calcium treatments, including calcium alone and calcium combined with vitamin D, compared to healthy controls. Specifically, the study highlighted that individuals with AD had a 64% higher chance of receiving a calcium prescription and a 125% higher likelihood of being referred for screening within two years of their diagnosis.
Despite these increased rates of screening and treatment, there remains a question about whether such efforts are effectively reducing the risk of osteoporosis and fractures in this vulnerable group. Factors such as age, sex, ethnic background, and use of analgesics also played significant roles in the treatment pathways for these patients, indicating that while there are advancements in management, the overall effectiveness still requires further investigation.
Read More
7
We explored how calcium treatment influences bone mineralization, particularly in the context of osteoporosis. Our study involved human mesenchymal stem cells (hMSCs) that were cultured in two different environments: one with calcium and another with dexamethasone, a medication often used to treat inflammation and other conditions.
Interestingly, while both treatments increased mineralization of hMSCs, we noted that levels of a specific microRNA, miR-125b, decreased with exposure to either calcium or dexamethasone. When we introduced a miR-125b mimic in the dexamethasone-treated cells, mineralization increased; however, it did the opposite in the calcium-treated cells. This suggests that calcium's effect can vary significantly depending on the context in which it is applied.
We also identified key targets of miR-125b that play roles in bone development, highlighting the complexity behind how calcium treatments might work in conjunction with other factors like dexamethasone. Overall, our findings contribute to a deeper understanding of bone metabolism and suggest that while calcium is important, its effectiveness might not be straightforward and may require further exploration.
Interestingly, while both treatments increased mineralization of hMSCs, we noted that levels of a specific microRNA, miR-125b, decreased with exposure to either calcium or dexamethasone. When we introduced a miR-125b mimic in the dexamethasone-treated cells, mineralization increased; however, it did the opposite in the calcium-treated cells. This suggests that calcium's effect can vary significantly depending on the context in which it is applied.
We also identified key targets of miR-125b that play roles in bone development, highlighting the complexity behind how calcium treatments might work in conjunction with other factors like dexamethasone. Overall, our findings contribute to a deeper understanding of bone metabolism and suggest that while calcium is important, its effectiveness might not be straightforward and may require further exploration.
Read More
User Reviews
USERS' SCORE
Moderately Good
Based on 28 Reviews
7.6
- All Reviews
- Positive Reviews
- Negative Reviews
9
Effective for prevention
1 people found this helpful
The ingredients are natural and effectively support osteoporosis prevention in the elderly. I consume it daily and recommend it highly.
Read More
10
High-quality calcium
This NOW Foods Coral Calcium is a top-notch product, perfect for those wanting to maintain bone health. It uses natural coral minerals for better absorption, effectively supplying the necessary calcium to prevent osteoporosis and improve overall bone and dental health. I wholeheartedly recommend this high-quality supplement.
Read More
9
Osteoporosis benefits
Excellent for patients with osteoporosis. It has great bioavailability and benefits.
Read More
9
Reduced fracture worry
I purchased this product for osteoporosis, and it has improved my bone health, reducing my worries about fractures.
Read More
9
Mother's satisfaction
This calcium is great. I regularly buy it for myself and my elderly mother who has osteoporosis. She is very satisfied with the product.
Read More
Frequently Asked Questions
6
Positive initial effects
So far, I feel these will benefit my osteoporosis. I've experienced no adverse effects after a week of taking them. I'm hopeful for improvements as I take one each morning.
9
Effective for prevention
1 people found this helpful
The ingredients are natural and effectively support osteoporosis prevention in the elderly. I consume it daily and recommend it highly.
2
Not helpful
Unfortunately, coral calcium was not helpful for my osteoporosis.
9
Reduced fracture worry
I purchased this product for osteoporosis, and it has improved my bone health, reducing my worries about fractures.
9
Mother's satisfaction
This calcium is great. I regularly buy it for myself and my elderly mother who has osteoporosis. She is very satisfied with the product.
9
Osteoporosis benefits
Excellent for patients with osteoporosis. It has great bioavailability and benefits.
8
We explored the effect of coral calcium and zeolite on bone health in mice, particularly focusing on postmenopausal bone loss caused by ovariectomy. After six months of supplementation, we observed that these treatments helped restore bone mass in the distal femur and improved bone structure.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
However, coral calcium's protection was less pronounced in other parts of the skeleton. Overall, while these supplements show promise for supporting bone health, the benefits may vary across different bone types.
4
We conducted a thorough review of various treatments for osteoporosis in people living with HIV, particularly focusing on the role of calcium. Our analysis included randomized controlled trials that compared different treatment strategies, such as calcium combined with medications like zoledronate or alendronate.
While zoledronate showed promising results in improving bone mineral density, calcium was often used alongside these treatments. Unfortunately, this combination makes it difficult to isolate the specific effects of calcium on osteoporosis. We found that alendronate, although it helped reduce certain bone turnover markers, did not significantly improve bone density.
Overall, the study indicates that while calcium plays a role in treatment combinations, its isolated impact on osteoporosis remains unclear. We emphasized the need for more focused research to determine calcium's true effectiveness in enhancing bone health for those affected by HIV.
While zoledronate showed promising results in improving bone mineral density, calcium was often used alongside these treatments. Unfortunately, this combination makes it difficult to isolate the specific effects of calcium on osteoporosis. We found that alendronate, although it helped reduce certain bone turnover markers, did not significantly improve bone density.
Overall, the study indicates that while calcium plays a role in treatment combinations, its isolated impact on osteoporosis remains unclear. We emphasized the need for more focused research to determine calcium's true effectiveness in enhancing bone health for those affected by HIV.
5
Calcium's risks for kidney stones
We explored the effects of calcium and vitamin D supplementation on osteoporosis, particularly focusing on the risk of kidney stones. In our study, 204 older adults in southwest China took daily doses of calcium and vitamin D for at least a year. We used various statistical analyses to understand the relationship between these supplements and kidney stone formation.
Our findings reveal that there is a potential link between the use of calcium supplements for osteoporosis and an increased risk of developing kidney stones. It seems that a history of kidney stones can elevate the likelihood of experiencing them again while undergoing such supplementation, likely due to higher urinary calcium levels.
While calcium is essential for bone health, our results suggest that patients need to be cautious. This research highlights the importance of monitoring kidney health while receiving calcium and vitamin D treatment to prevent complications like kidney stones.
Our findings reveal that there is a potential link between the use of calcium supplements for osteoporosis and an increased risk of developing kidney stones. It seems that a history of kidney stones can elevate the likelihood of experiencing them again while undergoing such supplementation, likely due to higher urinary calcium levels.
While calcium is essential for bone health, our results suggest that patients need to be cautious. This research highlights the importance of monitoring kidney health while receiving calcium and vitamin D treatment to prevent complications like kidney stones.
References
- Banu J, Varela E, Guerra JM, Halade G, Williams PJ, et al. Dietary coral calcium and zeolite protects bone in a mouse model for postmenopausal bone loss. Nutr Res. 2012;32:965. 10.1016/j.nutres.2012.09.009
- Wang JC, Chung SM, Wu PT, Tu YK, Lai PC, et al. Optimizing bone health in people living with HIV: insights from a network meta-analysis of randomized controlled trials. EClinicalMedicine. 2025;81:103103. 10.1016/j.eclinm.2025.103103
- Chen L, Lin S, He X, Ye J, Huang Y, et al. A calcium-loaded complex based on Antarctic krill protein and supplemented with pectin promotes calcium absorption and bone health. Int J Biol Macromol. 2025. 10.1016/j.ijbiomac.2025.141634
- Ma R, Romano E, Ashworth M, Vancampfort D, Solmi M, et al. Is there a disparity in osteoporosis referral and treatment among people with affective disorders? A ten-year data linkage study. Gen Hosp Psychiatry. 2025;94:56. 10.1016/j.genhosppsych.2025.02.009
- Chen J, Wang J, Jia W, Zhang Y, Li H, et al. Effect of salmon calcitonin combined with calcium antagonist on blood calcium and phosphorus ion concentration in osteoporosis rats. Eur J Med Res. 2025;30:115. 10.1186/s40001-025-02384-y
- Shi L, Bao Y, Deng X, Xu X, Hu J. Association between calcium and vitamin D supplementation and increased risk of kidney stone formation in patients with osteoporosis in Southwest China: a cross-sectional study. BMJ Open. 2025;15:e092901. 10.1136/bmjopen-2024-092901
- Joris V, Balmayor ER, van Griensven M. miR-125b differentially impacts mineralization in dexamethasone and calcium-treated human mesenchymal stem cells. Mol Ther Nucleic Acids. 2025;36:102446. 10.1016/j.omtn.2024.102446
