What to Give When Calcium is Low? Foods, Supplements, and Treatments

November 22, 2025 •

2 min read

According to the National Institutes of Health, over 50% of adult women consume inadequate levels of calcium from food sources. When blood calcium levels fall below the normal range, a condition known as hypocalcemia occurs. This article provides a comprehensive overview of what to give when calcium is low, including dietary changes, supplements, and when to seek medical help.

Quick Summary

Treatment for low calcium depends on its severity and cause, ranging from dietary adjustments and oral supplements to intravenous calcium for acute cases. Supporting nutrient intake, such as vitamin D and magnesium, is crucial for improving calcium absorption and metabolism.

Key Points

Address Severe Symptoms Immediately: Acute, severe hypocalcemia requires immediate intravenous calcium administration in a hospital setting for symptoms like seizures or heart problems.
Start with Diet: For mild deficiency, increase intake of calcium-rich foods like dairy, fortified plant-based milks, canned salmon, and dark leafy greens such as kale.
Choose the Right Supplement: Calcium carbonate is high in elemental calcium and cost-effective but requires food for absorption. Calcium citrate is more easily absorbed and can be taken anytime but is more expensive.
Combine with Vitamin D: Ensure adequate vitamin D intake, either through sunlight, fortified foods, or supplements, as it is essential for calcium absorption.
Limit Inhibitors: Reduce consumption of foods and beverages high in sodium, caffeine, and phosphates, which can hinder the body's ability to utilize calcium effectively.
Incorporate Exercise: Engage in regular weight-bearing exercises to help strengthen bones and prevent calcium loss over time.
Correct Magnesium Deficiency: A deficiency in magnesium can affect calcium metabolism and must be addressed for effective treatment of low calcium levels.

Understanding Hypocalcemia and Its Causes

Hypocalcemia is the medical term for having low calcium levels in the blood. While often caused by a simple dietary deficiency, it can also be triggered by a number of underlying health issues. Understanding the root cause is essential for effective treatment.

Causes of Calcium Deficiency

Low calcium can stem from several factors, including insufficient dietary intake, vitamin D deficiency (which impairs absorption), hypoparathyroidism, kidney disease, certain medications, and magnesium deficiency.

Immediate and Long-Term Interventions

The treatment for low calcium varies based on its severity and underlying cause.

Dietary Adjustments for Mild Calcium Deficiency

For mild cases, increasing dietary intake is recommended. Calcium-rich foods include dairy products, green leafy vegetables like kale (though spinach has oxalates that inhibit absorption), fish with edible bones such as sardines, and fortified foods like orange juice and plant-based milks.

Supplementation for Moderate Cases

When diet is insufficient, supplements may be needed. Calcium carbonate and calcium citrate are common types. Calcium carbonate is higher in elemental calcium and cheaper but requires stomach acid for absorption. Calcium citrate is absorbed more easily and can be taken without food but is more expensive. Vitamin D is often recommended alongside calcium supplements as it is vital for absorption.

Comparison of Calcium Supplements


Feature	Calcium Carbonate	Calcium Citrate
Elemental Calcium	High (approx. 40%)	Lower (approx. 21%)
Cost	Generally less expensive	More expensive
Absorption	Requires stomach acid; best taken with food	Does not require stomach acid; can be taken anytime
Tolerability	May cause gas, bloating, or constipation in some individuals	Generally gentler on the digestive system

Emergency Treatment for Severe Hypocalcemia

Severe, symptomatic hypocalcemia is a medical emergency treated with intravenous calcium, typically calcium gluconate, in a hospital setting with continuous monitoring for cardiac issues. Addressing the underlying cause, such as hypomagnesemia or hypoparathyroidism, is also crucial.

Other Considerations and Prevention

Maintaining adequate calcium involves diet, supplements, and lifestyle factors. Vitamin D and magnesium are important for calcium metabolism. Limiting calcium inhibitors like high sodium, caffeine, and phosphates can help. Weight-bearing exercise also supports bone health.

Conclusion

Treating low calcium requires an approach tailored to the severity and cause. Dietary changes are key for mild cases, while supplements can fill gaps. Severe hypocalcemia needs immediate medical attention. Always consult a healthcare professional for diagnosis and treatment. For more information on calcium and vitamin D, visit the National Institutes of Health website at ods.od.nih.gov.

Frequently Asked Questions

To increase calcium, eat dairy products like milk, yogurt, and cheese. Other excellent sources include canned sardines and salmon with bones, fortified plant-based milks and juices, and green leafy vegetables such as kale and broccoli.

Calcium carbonate is cost-effective with high elemental calcium but needs to be taken with food. Calcium citrate is more easily absorbed on an empty stomach and is a better option for those with low stomach acid or digestive issues.

Vitamin D is crucial for helping your body absorb calcium from the food you eat. Without sufficient vitamin D, even a high-calcium diet might not be enough to correct a deficiency.

Symptoms of severely low calcium include muscle cramps, numbness and tingling in the hands, feet, and face, seizures, confusion, memory loss, and in severe cases, an irregular heartbeat.

For mild deficiency, it is possible to correct low calcium with dietary changes. However, for moderate to severe cases, or if an underlying medical issue prevents proper absorption, supplements or other medical treatments are often necessary.

Preventing low calcium involves eating a balanced diet rich in calcium and vitamin D, getting regular sunlight exposure, performing weight-bearing exercise, and limiting substances that inhibit calcium absorption like excessive sodium and caffeine.

You should see a doctor if you experience symptoms of hypocalcemia, such as persistent muscle cramps, tingling, or fatigue. In emergency situations involving seizures or irregular heartbeats, seek immediate medical care.