Understanding the Differences: Calcium Citrate vs. Calcium Lactate
Calcium is a vital mineral essential for strong bones, nerve function, and muscle contractions. When dietary intake isn't enough, supplements can fill the gap, but not all calcium supplements are created equal. The most common forms are calcium carbonate and calcium citrate, but calcium lactate is also available. While both calcium citrate and calcium lactate are bioavailable forms, their chemical structure, elemental calcium content, and absorption characteristics vary, influencing which might be the better choice for you.
Elemental Calcium Content and Dosage
The amount of actual usable calcium, or elemental calcium, is a key metric when comparing supplements. A higher percentage means fewer pills are needed to reach the recommended daily intake. The percentage of elemental calcium for each is as follows:
- Calcium Citrate: Contains about 21% elemental calcium by weight. This means that for every 1000 mg of calcium citrate, you get 210 mg of elemental calcium.
- Calcium Lactate: Contains a lower percentage, approximately 13% elemental calcium by weight. As a result, you would need to take more tablets of calcium lactate to achieve the same dose of elemental calcium compared to calcium citrate.
Absorption and Digestive Tolerance
Absorption is perhaps the most significant difference between these two forms, particularly for individuals with specific digestive issues.
- Calcium Citrate: This form is often recommended for people with low stomach acid, which is common in older adults or those taking acid-blocking medications. It is absorbed equally well with or without food because it does not depend on stomach acid for dissolution. This makes it a highly flexible option for dosing.
- Calcium Lactate: Known for being highly soluble, calcium lactate is readily available for absorption in the small intestine and is generally gentle on the stomach. However, it is not often used for primary supplementation due to its lower elemental calcium concentration. It is more commonly used as a food additive (E327) or in specialized nutritional products.
Side Effects
While most calcium supplements can cause side effects like gas, bloating, or constipation, the specific type can influence the severity. Calcium carbonate is most commonly associated with these issues, while citrate and lactate are generally gentler on the digestive system.
- Calcium Citrate: Often better tolerated than calcium carbonate, especially for those prone to digestive upset.
- Calcium Lactate: This form is described as being less constipating than calcium carbonate and generally well-tolerated.
Special Considerations
- Kidney Stones: For individuals with a history of kidney stones, especially those made of calcium oxalate, calcium citrate is often the preferred choice. The citrate in the supplement can bind with calcium in the urine, inhibiting the formation of kidney stones.
- Low Stomach Acid: As noted, individuals with low stomach acid levels will absorb calcium citrate more effectively than calcium carbonate.
- Vegan Diets: While calcium lactate does not contain lactose, it is produced by fermenting sugars. Check the specific product, as some may use non-vegan ingredients, but it is often sourced in a vegan-friendly manner. Calcium citrate is generally vegan-friendly as it is derived from limestone or plant-based materials.
Comparison Table: Calcium Citrate vs. Calcium Lactate
| Feature | Calcium Citrate | Calcium Lactate |
|---|---|---|
| Elemental Calcium | ~21% | ~13% |
| Absorption | Can be taken with or without food; good for low stomach acid | High solubility; readily absorbed and gentle on the stomach |
| Common Use | Supplementation, especially for older adults or those with low stomach acid | Food additive (E327), less common for primary supplementation due to lower elemental calcium |
| Digestive Side Effects | Generally well-tolerated, less likely to cause constipation than carbonate | Gentle on the digestive system and less constipating than calcium carbonate |
| Cost | Typically more expensive than calcium carbonate | Variable, but not often used for cost-effective high-dose supplementation |
| Kidney Stones | Recommended for prevention as it can increase urinary citrate | No specific benefit noted for kidney stone prevention |
Conclusion
Choosing between calcium citrate and calcium lactate ultimately depends on your specific health profile and supplementation goals. Calcium citrate is the more practical option for daily calcium supplementation, offering a higher concentration of elemental calcium and reliable absorption regardless of stomach acid levels. It is particularly beneficial for older adults, individuals on acid-reducing medication, and those with a history of kidney stones. Conversely, calcium lactate's high solubility makes it a gentle option for sensitive stomachs, but its low elemental calcium content means more pills are needed for the same dose, making it a less common choice for primary supplementation. When making your decision, consider your digestive health, existing medical conditions, and cost. It is always wise to discuss your options with a healthcare provider to ensure you choose the safest and most effective supplement for your body. For further reading, authoritative sources like the Mayo Clinic's guide on calcium supplements provide additional insights on achieving the right balance.
Frequently Asked Questions
What is the main difference in absorption between calcium citrate and calcium lactate?
Calcium citrate absorbs well regardless of stomach acid levels, making it ideal for those with low stomach acid, while calcium lactate is highly soluble and readily absorbed in the small intestine, providing a gentler option for sensitive stomachs.
Is calcium lactate suitable for people with sensitive stomachs?
Yes, calcium lactate is known for being very soluble and gentle on the digestive system, making it a good choice for people who experience gas, bloating, or constipation with other calcium forms like calcium carbonate.
Which supplement is better for preventing kidney stones?
Calcium citrate is often recommended for preventing kidney stones, as the citrate can help inhibit the formation of calcium oxalate stones.
Can I take calcium citrate and calcium lactate on an empty stomach?
Yes, both calcium citrate and calcium lactate can be taken on an empty stomach. Calcium citrate's absorption is not dependent on stomach acid, while calcium lactate is highly soluble and easily absorbed without food.
How much elemental calcium do I get from each supplement?
Calcium citrate contains approximately 21% elemental calcium, while calcium lactate provides a lower amount, around 13% elemental calcium.
Is calcium lactate vegan?
Calcium lactate is typically vegan-friendly because the lactate is derived from the fermentation of sugar, not dairy. However, checking the specific product's label or contacting the manufacturer is always recommended.
Why is calcium lactate less common in supplements compared to citrate?
Calcium lactate has a lower elemental calcium content, meaning more pills are needed to achieve a sufficient dose. For this reason, it is less practical for high-dose supplementation and is more frequently used as a food additive.
