Takeaways
- Calcium strengthens bones and teeth
- Vitamin D improves calcium absorption
- Dairy and leafy greens provide calcium
- Supplements can help meet daily needs
- Lifestyle factors affect calcium levels
Understanding Calcium
Calcium is a vital mineral for human health, playing a key role in building and maintaining strong bones and teeth.[1] It also supports proper muscle function and nerve communication throughout the body.[2] Your body stores most of its calcium within the bones, drawing upon these reserves as needed.[3]
Beyond bone health, calcium is essential for other bodily functions. It helps the blood clot properly after an injury and assists in regulating the heart’s rhythm.[4] Furthermore, calcium aids in the release of various hormones.[5] Without sufficient calcium, the body cannot perform these vital functions correctly.
The human body cannot produce calcium on its own; therefore, it must be obtained through the diet or from supplements.[6] Understanding how calcium works is key to meeting your individual needs, and this knowledge supports your overall health and well-being.
Calcium and Bone Health
Building Strong Bones
Calcium provides the fundamental structure of bones and teeth, working in combination with other minerals to create hard, durable tissue. This process of building bone and teeth begins in childhood and continues throughout a person’s life.[7]
Your body continuously removes old calcium from bones and replaces it with new calcium in a process called bone remodeling.[8] This constant turnover keeps bones strong and healthy. Insufficient calcium intake can lead to weak and brittle bones.[9]
Osteoporosis Prevention
Osteoporosis is a condition where bones become weak and fragile, significantly increasing the risk of fractures.[10] A major contributing factor to osteoporosis is consistently low calcium intake over time.[11]
Ensuring you get enough calcium helps protect against osteoporosis by keeping bones dense and strong.[12] This is particularly important as you age, because the body’s ability to absorb calcium tends to decrease naturally over time.[13]
Factors that increase your risk for developing osteoporosis include:
- Age (over 50)
- Gender (women are at higher risk)
- Family history
- Low body weight
- Smoking
- Excessive alcohol consumption
- Lack of exercise
Calcium Absorption
Factors Affecting Absorption
Calcium absorption is a complex process. The body does not absorb all the calcium you consume from food or supplements. Several factors can impact how much calcium your body is actually able to use.
Age significantly affects calcium absorption. Young children can absorb as much as 60% of the calcium they get from food. Adults, on the other hand, typically absorb between 15% and 20%.[14] Understanding these absorption differences helps in planning appropriate calcium intake for various age groups.
Enhance Absorption | Inhibit Absorption |
---|---|
Vitamin D | Phytic acid |
Vitamin C | Oxalic acid |
Lactose | High sodium intake |
Adequate protein | Excessive caffeine |
Vitamin D and Calcium
Vitamin D is vital for calcium absorption; it enables the body to use calcium from consumed food.[15] Without sufficient vitamin D, the body cannot effectively absorb calcium, regardless of intake levels.[16]
You can obtain vitamin D through sun exposure, specific foods, and dietary supplements. Good food sources of vitamin D include fatty fish, egg yolks, and fortified foods. The recommended daily intake of Vitamin D varies based on age and other individual factors.
Dietary Sources of Calcium
Dairy Products
Dairy products are a well-known, rich source of calcium that the body absorbs easily.[17] Common dairy sources include milk, yogurt, and cheese, providing a readily accessible way to increase calcium intake.
The amount of calcium varies among different dairy products. For example, one cup of milk usually contains about 300 mg of calcium. Hard cheeses typically contain more calcium than softer varieties.
Plant-Based Sources
Plant-based foods can also provide calcium; however, the calcium in plants is often less bioavailable.[18] This means that the body absorbs less calcium from plant sources compared to dairy products.
Some plants contain compounds that can interfere with calcium absorption. For example, spinach is high in oxalates, which can bind to calcium and hinder its absorption.[19] Despite these challenges, many plant foods are still considered good sources of calcium.
Excellent plant-based sources of calcium include:
- Leafy greens (kale, collard greens)
- Fortified plant milks
- Tofu (made with calcium sulfate)
- Almonds and almond butter
- Figs
- Chia seeds
Calcium Supplements
Types of Supplements
Calcium supplements are available in several forms, including calcium carbonate and calcium citrate.[20] Each type has distinct absorption rates, and each is best suited for different uses and circumstances.
Selecting the right type of calcium supplement depends on multiple factors, such as your age, existing health conditions, and any medications you are currently taking. Consulting a healthcare professional is a good idea before beginning any supplementation.
Supplement Type | Absorption | Best Taken |
---|---|---|
Calcium Carbonate | 40% | With food |
Calcium Citrate | 30% | Any time |
Calcium Gluconate | 25% | With food |
Calcium Lactate | 30% | Any time |
Supplement Safety
Calcium supplements can sometimes cause side effects, such as constipation and bloating.[21] In less common cases, they can increase the risk of kidney stone formation in some individuals.[22]
To use calcium supplements safely, follow these guidelines:
- Don’t exceed the recommended dose
- Take calcium in small doses throughout the day
- Avoid taking iron supplements at the same time
- Inform your doctor about all supplements you take
Daily Calcium Requirements
Age and Gender Considerations
Calcium needs change throughout an individual’s life. Children and teenagers have higher needs to support their rapid growth. Adults require calcium to maintain existing bone health.
Women generally need more calcium than men due to hormonal differences and the demands of pregnancy.[23] Postmenopausal women especially need higher amounts of calcium.
Recommended daily calcium intake based on age group:
- Infants 0-6 months: 200 mg
- Infants 7-12 months: 260 mg
- Children 1-3 years: 700 mg
- Children 4-8 years: 1,000 mg
- Adolescents 9-18 years: 1,300 mg
- Adults 19-50 years: 1,000 mg
- Women 51+ years: 1,200 mg
- Men 51-70 years: 1,000 mg
- Men 71+ years: 1,200 mg
Special Populations
Pregnant and breastfeeding women need additional calcium to support their own health and the development of their baby.[24] The generally recommended daily intake during pregnancy is 1,000 mg for most pregnant individuals.
Athletes and very active people may need a bit more calcium because they lose some through sweat.[25] Exercise also builds bone strength, thus requiring a higher calcium level. Usually, a balanced diet is sufficient for meeting these increased needs.
Calcium Deficiency
Signs and Symptoms
Calcium deficiency can cause a wide variety of symptoms, and these often develop slowly over time.[26] The early signs of a deficiency may be subtle and easily overlooked.
Low levels of calcium can impact multiple body systems. This can lead to weakened bones, painful muscle cramps, and general fatigue.[27] A severe deficiency can result in more serious health issues.
Symptoms that might suggest calcium deficiency include:
- Numbness and tingling in fingers
- Muscle cramps
- Fatigue
- Poor appetite
- Irregular heartbeat
- Weak and brittle nails
- Slow hair growth
Long-Term Health Impacts
Long-term or chronic calcium deficiency has serious consequences, including the development of osteoporosis and an increased risk of bone fractures.[28] This is especially concerning for older adults.
Insufficient calcium intake can affect more than just bone health, as it is linked to an increased risk of high blood pressure.[29] Some studies also suggest a potential link between low calcium levels and certain types of cancer.[30] However, further research is required to solidify these findings.
Calcium and Other Nutrients
Nutrient Interactions
Calcium interacts with numerous other nutrients, and these interactions can affect its absorption and use by the body. Understanding these relationships is essential for optimizing overall nutrition.
Some nutrients can enhance calcium absorption, while others can hinder it.[31] For example, vitamin D significantly improves how the body uses calcium.[32] On the other hand, iron supplements can reduce calcium absorption if taken at the same time.[33]
Balancing Act
Maintaining a balanced diet that includes a variety of nutrient-rich foods supports good calcium absorption. It also involves considering the timing of when different nutrients are consumed to optimize their effectiveness.
To ensure calcium is balanced with other nutrients:
- Pair calcium-rich foods with vitamin D sources
- Avoid taking calcium and iron supplements together
- Include protein-rich foods in your diet
- Limit sodium intake, which can increase calcium loss
Calcium Myths and Facts
Many myths and misconceptions surround calcium intake, which can lead to confusion about how to get proper nutrition. It’s helpful to clarify some of these common misunderstandings.
Scientific evidence refutes many of the common myths about calcium.[34] Understanding the facts is essential for making informed nutritional choices and ensuring you are meeting your calcium needs effectively.
Here are some common calcium myths, along with the factual information:
- Myth: Only dairy provides enough calcium Fact: Many non-dairy foods are rich in calcium
- Myth: More calcium is always better Fact: Excessive calcium can have negative health effects
- Myth: Calcium supplements are necessary for everyone Fact: Many people can meet needs through diet alone
- Myth: Calcium alone prevents osteoporosis Fact: Other factors like exercise also play a role
Calcium Beyond Bones
Heart Health
Calcium plays a role in regulating heart function, helping to control heart rhythm and blood pressure.[35] Some studies suggest that adequate calcium intake might reduce the risk of cardiovascular disease.[36]
However, the relationship between calcium and heart health is complex, and more studies are needed. Excessive calcium from supplements might actually increase risks to the heart, therefore getting calcium from food sources is considered a safer approach.
Muscle Function
Calcium is essential for muscle contractions, as it helps muscles relax and contract properly.[37] This process is fundamental for normal movement and physical activity.
Adequate calcium can also support exercise performance and reduce muscle cramping that occurs during physical activity.[38] Calcium also plays a role in post-exercise recovery.
Calcium Throughout Life
Childhood and Adolescence
Childhood is an important time for building strong bones and ensuring adequate calcium intake is critical.[39] Getting enough calcium during these years helps establish a solid foundation for lifelong bone health.
Strategies to help ensure sufficient calcium intake in young people:
- Include dairy or fortified alternatives in meals
- Offer calcium-rich snacks like yogurt or cheese
- Encourage outdoor play for vitamin D production
- Limit sodas, which can replace calcium-rich drinks
Adulthood and Aging
Calcium needs evolve as we age. Adults require consistent calcium intake to maintain bone density, and this is especially crucial after the age of 50.[40]
Calcium supports healthy aging by helping to maintain bone strength and reduce the risk of fractures.[41] It may also contribute to heart and muscle health in older adults.
Tips for maintaining calcium intake throughout adulthood:
- Include calcium-rich foods in every meal
- Choose calcium-fortified products when available
- Consider supplements if diet is lacking
- Stay active to support bone health
- Get regular bone density screenings after 50
FAQ: People Also Ask
How much calcium do I need daily?
Can I get enough calcium without dairy?
What happens if I consume too much calcium?
How does caffeine affect calcium absorption?
Is calcium linked to kidney stones?
Can calcium supplements interfere with medications?
Calcium is indeed crucial for the formation and maintenance of bone and teeth, making it an essential mineral for human health.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
Calcium ions are critical for both muscle contraction and the transmission of nerve impulses.
Source: “Regulation of smooth muscle contraction by monomeric non‐RhoA GTPases” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7429483/
The skeleton stores the majority of the body’s calcium, which can be released into the bloodstream when needed to maintain serum calcium levels.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
Calcium is a key factor in the blood clotting cascade and it’s essential for the heart’s electrical activity which controls heart rhythm.
Source: “LRP5 regulates cardiomyocyte proliferation and neonatal heart regeneration by the AKT/P21 pathway” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9097834/
Calcium ions play a crucial role in the secretion of various hormones throughout the body by participating in the signaling process that causes hormone release.
Source: “Posters” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11208286/
Calcium is an essential mineral that the body can’t produce, so dietary intake is the only way for humans to get it.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
Bone development occurs mostly during childhood and adolescence but bone remodeling is a continuous process throughout life.
Source: “Bone remodeling: an operational process ensuring survival and bone mechanical competence” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9293977/
Bone remodeling is a vital process that ensures bone strength by constantly removing old bone tissue and replacing it with new tissue.
Source: “Bone remodeling: an operational process ensuring survival and bone mechanical competence” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9293977/
Inadequate calcium intake compromises bone density and strength, leading to weaker bones that are prone to fracture.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
Osteoporosis is a disease in which bone density and quality are reduced, leading to increased fragility and fracture risk.
Source: “UK clinical guideline for the prevention and treatment of osteoporosis” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8979902/
Consistently insufficient dietary calcium is a significant factor that can cause osteoporosis, although it is not the only factor
Source: “UK clinical guideline for the prevention and treatment of osteoporosis” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8979902/
Sufficient calcium intake supports bone health by ensuring adequate bone mineralization and density, protecting against the effects of osteoporosis.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
As people age, their digestive system becomes less efficient at absorbing calcium from food, making adequate calcium intake essential to counteract declining absorption.
Source: “Calcium Absorption from Food Products: Food Matrix Effects” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8746734/
Children and adolescents have high calcium absorption rates due to their bone growth, whereas adult calcium absorption is less efficient.
Source: “Calcium Absorption from Food Products: Food Matrix Effects” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8746734/
Vitamin D is essential for the body to absorb calcium in the digestive tract and utilize the calcium available.
Source: “The Role of Vitamin D and Vitamin D Binding Protein in Chronic Liver Diseases” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9503777/
Insufficient vitamin D compromises the body’s ability to absorb dietary calcium and to use the calcium available, regardless of calcium intake.
Source: “The Role of Vitamin D and Vitamin D Binding Protein in Chronic Liver Diseases” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9503777/
Dairy products are an easily accessible and bioavailable source of calcium for most people.
Source: “Chinese residents’ knowledge about and behavior towards dairy products: a cross-sectional study” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9943042/
The bioavailability of calcium in plants is often lower due to the presence of compounds that hinder its absorption, such as oxalates and phytates.
Source: “Relative Bioavailability of Trace Minerals in Production Animal Nutrition: A Review” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9367456/
Oxalates bind with calcium in the digestive tract, forming insoluble compounds that the body cannot absorb, thus reducing the amount of calcium available.
Source: “The effects of extraction techniques and quantitative determination of oxalates in Nerium oleander and feeds” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6556938/
Calcium carbonate and calcium citrate are frequently used forms of calcium supplements, each with different absorption characteristics.
Source: “Oral calcium and vitamin D supplements differentially alter exploratory, anxiety-like behaviors and memory in male rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10420380/
The most common side effects of calcium supplements include constipation and gastrointestinal issues, such as bloating, gas, and stomach pain.
Source: “Comparison between the American and the European Systems of Monitoring Adverse Effects of Dietary Supplements and Their Usefulness on the Polish Market” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9859348/
Excessive calcium supplementation can increase the risk of kidney stone formation, especially in individuals who are already prone to them.
Source: “Relationship between Serum Selenium Level and Self-Reported History of Kidney Stone” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10255404/
Women often need more calcium than men due to hormonal changes across the lifecycle (such as pregnancy and menopause) that affects their calcium needs.
Source: “Modern India and Dietary Calcium Deficiency—Half a Century Nutrition Data—Retrospect–Introspect and the Road Ahead” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056136/
Pregnant and breastfeeding women need extra calcium to support fetal development and milk production.
Source: “Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6517256/
Athletes may experience slightly higher calcium losses through sweat, necessitating greater calcium intake. However, a balanced diet is usually sufficient.
Source: “Evolution of Vitamin D Status and Vitamin D Receptor Gene Expression Among Professional Handball Athletes During a Competitive Period. Relationship with Body Composition, Calcium, Magnesium and Phosphorous” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10859345/
The symptoms of calcium deficiency typically develop slowly, and their impact may not be immediately obvious.
Source: “Modern India and Dietary Calcium Deficiency—Half a Century Nutrition Data—Retrospect–Introspect and the Road Ahead” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056136/
Hypocalcemia can manifest in several ways, including weakened bones, muscle cramps, and fatigue due to calcium’s diverse roles in the body.
Source: “Modern India and Dietary Calcium Deficiency—Half a Century Nutrition Data—Retrospect–Introspect and the Road Ahead” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056136/
Long-term calcium deficiency can cause decreased bone density and increased susceptibility to fractures due to reduced bone strength.
Source: “Modern India and Dietary Calcium Deficiency—Half a Century Nutrition Data—Retrospect–Introspect and the Road Ahead” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8056136/
A growing body of research suggests that adequate calcium is necessary for blood pressure regulation and that its deficiency may contribute to hypertension.
Source: “Home blood pressure monitoring: methodology, clinical relevance and practical application: a 2021 position paper by the Working Group on Blood Pressure Monitoring and Cardiovascular Variability of the European Society of Hypertension” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9904446/
Some research suggests potential links between low calcium levels and some cancer types. However, additional investigation is needed to understand the nature of this association.
Source: “Endoplasmic Reticulum Calcium Pumps and Tumor Cell Differentiation” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7247589/
Nutrient interactions can influence calcium absorption; some nutrients facilitate its uptake while others inhibit it.
Source: “Estimating Excreted Nutrients to Improve Nutrient Management for Grazing System Dairy Farms” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10135339/
Vitamin D plays a critical role in calcium absorption, greatly improving its uptake and utilization by the body.
Source: “The Role of Vitamin D and Vitamin D Binding Protein in Chronic Liver Diseases” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9503777/
Iron supplements may compete with calcium for absorption in the gut, so co-ingestion could decrease the absorption of both minerals.
Source: “Hepcidin induces intestinal calcium uptake while suppressing iron uptake in Caco-2 cells” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8513844/
Many popular misconceptions about calcium are contradicted by scientific research and evidence-based nutritional guidelines.
Calcium is a key player in heart function, affecting heart rhythm, muscle contraction and relaxation, and blood pressure by its effects on blood vessels.
Source: “LRP5 regulates cardiomyocyte proliferation and neonatal heart regeneration by the AKT/P21 pathway” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9097834/
While some observational studies suggest a link between higher calcium intake and a reduced risk of cardiovascular disease, more robust, randomized controlled trials are needed to confirm these findings.
Source: “Severe mental illness: cardiovascular risk assessment and management” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10972692/
Calcium ions are crucial for triggering and regulating the cycle of muscle contraction and relaxation by affecting the structure of muscle proteins.
Source: “Regulation of smooth muscle contraction by monomeric non‐RhoA GTPases” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7429483/
While further study is warranted, sufficient calcium can support muscle function, which can improve performance and reduce exercise-induced muscle cramping.
Source: “Running exercise with and without calcium supplementation from tuna bone reduced bone impairment caused by low calcium intake in young adult rats” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10264423/
Adequate calcium during childhood is important for bone development, since it is the major bone building period
Source: “Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6517256/
Maintaining adequate calcium intake as an adult, and especially after the age of 50, is important for maintaining bone density and protecting against osteoporosis.
Source: “Abstracts from the 2023 Annual Meeting of the Society of General Internal Medicine” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10323075/
Calcium plays a key role in healthy aging by helping to maintain bone mass and strength, thereby reducing the risk of fractures.
Source: “World guidelines for falls prevention and management for older adults: a global initiative” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9523684/
The specific daily calcium needs differ based on individual factors including age, gender, and life stage, with most adults requiring about 1000-1200mg per day.
Source: “Calcium Intake and Metabolism in Infants and Young Children: A Systematic Review of Balance Studies for Supporting the Development of Calcium Requirements” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9526821/
Adequate calcium intake is achievable through various non-dairy sources, such as leafy green vegetables, fortified plant milks, and some fish species.
Source: “Nutritional Content and Health Profile of Non-Dairy Plant-Based Yogurt Alternatives” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8619131/
Excessive calcium supplementation can cause side effects like constipation and increase the risk of kidney stone formation in some individuals.
Source: “Interventions for American cutaneous and mucocutaneous leishmaniasis” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8094931/
Caffeine may cause a minor decrease in calcium absorption and may increase calcium excretion through urine, which has been observed in some studies.
Source: “Key Findings and Implications of a Recent Systematic Review of the Potential Adverse Effects of Caffeine Consumption in Healthy Adults, Pregnant Women, Adolescents, and Children” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6212940/
Studies suggest that while high doses of supplemental calcium may elevate the risk of kidney stones, calcium obtained through dietary sources may actually have a protective effect.
Source: “Kidney Stone Prevention” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10201681/
Calcium can interfere with the absorption of some medications, such as tetracycline antibiotics and thyroid hormones, due to possible binding and decreased uptake.
Source: “Self-Reported Medication Use and Urinary Drug Metabolites in the German Chronic Kidney Disease (GCKD) Study” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8729827/