NOW® Calcium Citrate 100 Tablets: High-Absorption Bone & Mineral Support

NOW® Calcium Citrate (SKU: N1230) delivers 600 mg of bioavailable elemental calcium per serving, specifically chelated to organic citric acid so your digestive tract can absorb it easily. Unlike traditional, chalky calcium carbonate supplements that require dense stomach acid to break down, calcium citrate dissolves effortlessly on contact—making it the preferred choice for adults over 50, individuals taking acid-reducing medications (such as PPIs or H2 blockers), and anyone prone to occasional digestive sluggishness.

Strong bones require far more than just raw calcium. NOW Foods combines this premium calcium chelate with an evidence-based matrix of synergistic bone co-factors: Vitamin D2 (ergocalciferol) to carry calcium across your gut lining, Magnesium to direct calcium into the skeletal structure, and fully reacted Albion™ chelated Zinc, Copper, and Manganese to help synthesize the flexible collagen scaffolding that keeps bones resilient against fractures.

• Formulation: 600 mg Elemental Calcium + 300 mg Magnesium per 2-tablet serving
• Bottle Count: 100 vegetarian-coated tablets (50 full days of targeted bone nourishment)
• Digestive Friendly: Highly soluble; does not trigger the gas, bloating, or heavy constipation common with rock-derived calcium carbonate
• Dietary Standards: Certified Non-GMO, Vegan/Vegetarian, Halal, and Kosher (Triangle K)

The Bioavailability Breakdown: Why Calcium Citrate Outperforms Calcium Carbonate

Many mass-market bone supplements rely on calcium carbonate because it is cheap and physically dense. However, calcium carbonate is chemically identical to limestone or chalk; it requires a flood of concentrated hydrochloric stomach acid (pH below 2.0) simply to separate the calcium ion from its carbonate shell so your body can take it in.

In contrast, calcium citrate is pre-acidified. Because the calcium molecule is already chemically bound to natural citric acid, it does not rely on stomach acid to break apart. It dissolves smoothly in both low-acid and neutral environments, whether taken with a large meal or on a completely empty stomach.

Clinical Evidence Supporting Calcium Citrate:

• Absorption in Low-Acid Environments: Landmark research published in The New England Journal of Medicine demonstrated that individuals with reduced gastric acid (achlorhydria) absorbed only 4% of calcium from calcium carbonate, but absorbed over 45% of calcium from calcium citrate (Recker RR, N Engl J Med, 1985; PMID: 4075678).
• Superior Overall Bioavailability: A comprehensive meta-analysis of clinical absorption trials confirmed that calcium citrate is absorbed 22% to 27% more effectively than calcium carbonate regardless of whether it is taken with or without food (Sakhaee K et al., Am J Ther, 1999; PMID: 10416949; Heaney RP et al., J Am Coll Nutr, 2001; PMID: 11329115).
• Collagen Framework Support: Double-blind clinical trials show that combining bioavailable calcium with trace minerals like zinc, copper, and manganese halts spinal bone loss significantly better than calcium alone by supporting the enzymatic cross-linking of bone collagen (Strause L et al., J Nutr, 1994; PMID: 8027735).

Supplement Facts & Complete Ingredients Listing

Every two-tablet serving delivers an exact balance of pure elemental minerals and co-vitamins. We believe in complete label transparency with no hidden fillers or undisclosed proprietary blends.

Serving Size: 2 Tablets | Servings Per Container: 50 | Item UPC: 733739012302

Other Ingredients: Hydroxypropyl Cellulose, Vegetarian Coating [hypromellose (cellulose), calcium carbonate, glycerin], Croscarmellose Sodium, Silicon Dioxide, Magnesium Stearate (vegetable source), Citric Acid, Maltodextrin, and Stearic Acid (vegetable source).

Allergen Safety Information: Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut, or sesame ingredients. Produced in a thoroughly inspected, third-party cGMP facility that processes other ingredients containing these allergens. Suitable for strict vegans and vegetarians.

NOW® Brand Quality: World-Class Lab Testing & Contaminant Controls

Because calcium is mined from natural earth elements, raw minerals carry a constant real-world risk of environmental contamination, particularly heavy metals like lead, cadmium, and arsenic. You should never guess about the purity of what enters your body. NOW Foods operates one of the most advanced private analytical testing facilities in the nutritional industry, performing more than 31,000 comprehensive quality checks each month across raw materials, in-process blending, and packaged finished goods.

• Trace Heavy Metal Detection (ICP-MS): NOW tests mineral powders utilizing Inductively Coupled Plasma Mass Spectrometry (ICP-MS). This instrument detects heavy metal toxins (lead, arsenic, cadmium, and mercury) down to trace parts per billion (ppb), ensuring raw materials comply with stringent USP, FDA, and California Proposition 65 limits.
• Elemental Potency Verification (ICP-OES): Using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), NOW chemists verify the precise elemental concentration of calcium, magnesium, zinc, copper, and manganese to ensure every tablet meets 100% of the active potency promised on the label.
• Automated Microbial Screening: Every batch undergoes strict microbiological screening using automated detection tools (including the Soleris® system and RiboPrinter® microbial characterization) to ensure absolute absence of Salmonella, E. coli, yeast, mold, and environmental bacterial contaminants.
• Accredited Quality Standard: Analytical testing is executed inside ISO/IEC 17025:2017 accredited in-house laboratories, and manufacturing facilities are certified cGMP (Current Good Manufacturing Practices) by Intertek and the Natural Products Association (NPA).

✓ 100% PCR Recycled Resin Bottle  |  ✓ Zero Adulterants  |  ✓ Verified True-to-Label Potency

How to Take, Optimal Timing & Real-World Precautions

To get the highest bone-strengthening benefit from your calcium supplement, how and when you take your tablets matters just as much as the quality of the formula itself.

Practical Usage Recommendations:

• Daily Dose: Take 2 tablets daily. For maximum intestinal absorption, we strongly advise dividing your doses: take 1 tablet with breakfast or lunch, and 1 tablet with dinner.
• Why Divide Doses? The human gut can only absorb approximately 500 mg of elemental calcium at any one time before intestinal transport channels saturate. Spreading your intake across the day doubles your actual usable uptake compared to taking both tablets at once (Harvey JA et al., J Bone Miner Res, 1988).
• Meal Flexibility: While calcium citrate does not require stomach acid and can be taken on an empty stomach, taking it alongside a meal or light snack remains standard best practice to optimize absorption of the companion fat-soluble Vitamin D.

Important Medication Spacing & Drug Interactions:

• Thyroid Hormone Replacement: Calcium binds to thyroid medications (such as Levothyroxine or Synthroid) in the stomach, blocking their absorption. Always separate your calcium dose from thyroid medications by at least 4 hours.
• Prescription Antibiotics: Calcium can form insoluble complexes with quinolone antibiotics (e.g., Cipro) and tetracyclines (e.g., Doxycycline). Take antibiotics at least 2 hours before or 4 to 6 hours after calcium.
• Iron Supplements: Calcium and iron compete directly for the same intestinal DMT-1 transporters. For maximum red blood cell support, take iron supplements at a separate time of day.
• Medical Conditions: If you are pregnant, nursing, have a history of hypercalcemia, severe kidney dysfunction, or sarcoidosis, consult your personal physician prior to supplementation.

Why Order Your NOW Supplements From VitaNet®, LLC?

In today's open online marketplace, buying vitamins can feel like a gamble. Thousands of third-party resellers sell inventory stored in unconditioned containers, products nearing expiration, or unverified returns. When you shop with VitaNet®, LLC, you are ordering from an authentic, licensed health retailer with verifiable roots.

• Online Pioneer Since 1995: Founded in 1995 as an independent, family-owned Ohio retailer, VitaNet® has delivered authentic nutritional supplements nationwide for over 31 years.[cite: 1]
• 100% Risk-Free Money-Back Guarantee: We stand unconditionally behind everything we sell. If a product does not meet your expectations, we provide a complete refund and even pay the return shipping costs—even on opened bottles.[cite: 1]
• Direct-from-Manufacturer Authenticity: All NOW Foods products are received directly through verified manufacturer distribution lines and housed in our climate-regulated storage facility in Hartville, Ohio.[cite: 1] You will never receive aged or liquidated stock.
• BBB A+ Accredited Integrity: VitaNet® holds an A+ accreditation from the Better Business Bureau, reflecting over three decades of personalized customer service, transparent communication, and honest pricing.[cite: 1]

Need help finding the right mineral dosage or combining your daily vitamins? Our knowledgeable Ohio team is always available during business hours by phone or email.[cite: 1]

Frequently Asked Questions (FAQ)

1. Why is calcium citrate recommended over calcium carbonate for seniors and bariatric patients?

As we age, our stomachs naturally produce less gastric acid (a condition known as hypochlorhydria). Similarly, bariatric surgeries bypass portions of acid-producing stomach tissue. Because calcium carbonate requires strong acid to dissolve, seniors and bariatric patients absorb very little of it. Calcium citrate is pre-acidified and dissolves completely regardless of stomach acid levels, ensuring reliable mineral delivery into the bloodstream.

2. Can I take NOW Calcium Citrate if I am taking Prilosec, Nexium, or Pepcid?

Yes. Calcium citrate is the specific form recommended by physicians for patients using proton pump inhibitors (PPIs) or H2 acid blockers. These medications shut down stomach acid, which cripples calcium carbonate breakdown. Calcium citrate bypasses this dependency entirely, dissolving and absorbing smoothly even when stomach acid is completely suppressed.

3. Does NOW Calcium Citrate cause constipation or stomach bloating?

Calcium citrate has a far lower rate of digestive side effects than calcium carbonate. Furthermore, NOW Foods includes 300 mg of Magnesium in this formula. Magnesium naturally supports healthy bowel motility and muscle relaxation, which counteracts the constipating tendency of calcium to keep your digestion smooth and comfortable.

4. Why does this formula include Zinc, Copper, and Manganese?

Bone is living tissue made up of a hard mineral crust embedded on a flexible collagen mesh. While calcium and magnesium harden the bone, zinc, copper, and manganese are required by enzymes (like lysyl oxidase) to build the underlying collagen scaffolding. NOW uses Albion™ amino acid chelates for these trace minerals to ensure optimal absorption without competing against calcium.

5. Is this product vegan, and does it contain gluten or dairy?

Yes, NOW Calcium Citrate 100 Tablets is 100% vegan. The Vitamin D is sourced as ergocalciferol (D2) rather than animal-derived lanolin, and the tablet coating is vegetable-based cellulose. It is formulated free of wheat, gluten, soy, milk, egg, fish, shellfish, and tree nuts.

6. Can I take both tablets together once a day?

While taking both at once is safe, dividing your intake into 1 tablet in the morning and 1 tablet in the evening is clinically proven to provide higher total mineral absorption. The intestinal wall absorbs calcium most efficiently in single doses of 500 mg or less.