Is calcium lactate a good form of calcium to supplement with?

Calcium Lactate as a Calcium Supplement

Calcium lactate is not the preferred form of calcium supplementation due to its lower elemental calcium content (13%) compared to more efficient options like calcium carbonate (40%) or calcium citrate (21%). 1, 2

Comparison of Calcium Supplement Forms

Calcium supplements vary significantly in their elemental calcium content, which directly impacts their effectiveness and dosing requirements:

• Calcium carbonate: 40% elemental calcium - most economical option, must be taken with meals 2, 3
• Calcium citrate: 21% elemental calcium - better tolerated, can be taken with or without food 2, 3
• Calcium lactate: 13% elemental calcium - requires more pills to achieve equivalent dosing 1
• Calcium gluconate: 9% elemental calcium - not practical for oral supplementation due to low concentration 3

Efficacy and Absorption Considerations

While some research suggests that calcium from different sources (including calcium lactate) may have similar bioavailability in controlled studies 4, the practical implications of the lower elemental calcium content in calcium lactate are significant:

• More pills/larger doses are required to achieve the same elemental calcium intake
• This can lead to reduced adherence and increased gastrointestinal side effects
• The 2025 Calcium Supplementation Guidelines recommend limiting calcium supplements to 500 mg elemental calcium per dose for optimal absorption 2

Clinical Recommendations

For patients requiring calcium supplementation:

1. First-line options:

   • Calcium carbonate (40% elemental calcium) - most cost-effective, take with meals
   • Calcium citrate (21% elemental calcium) - better for patients with reduced stomach acid or taking acid-reducing medications

2. Dosing considerations:

   • Limit to 500 mg elemental calcium per dose for optimal absorption 2
   • Space doses throughout the day rather than taking all at once 5
   • Total supplementation generally should not exceed 500 mg daily when added to average dietary intake 2

3. Special populations:

   • For patients with achlorhydria or those taking histamine-2 blockers or proton pump inhibitors, calcium citrate is preferred 3
   • In children with CKD, calcium lactate may be considered as it is generally well tolerated, but other options provide more elemental calcium per dose 1

Potential Pitfalls and Considerations

• Excessive supplementation: Total calcium intake (diet plus supplements) should generally not exceed 1400 mg daily to avoid increasing cardiovascular risk 2
• Medication interactions: Calcium can interact with certain medications including antibiotics and thyroid medications
• Side effects: Common side effects include constipation, bloating, and gas; less common but serious side effects include kidney stones 2

Dietary Sources vs. Supplements

The 2025 guidelines emphasize that dietary calcium should be prioritized over supplements whenever possible 2. High-calcium foods include:

• Dairy products (milk, yogurt, cheese)
• Leafy greens (kale, Chinese cabbage)
• Calcium-fortified foods and beverages

Supplements should only be used when dietary intake is insufficient to meet recommended daily intake levels.