Kirkland Signature Ultra Strength Antacid Calcium Carbonate 1000 mg Assorted Berry Flavors
Brand: Kirkland Signature · Form: TABLET [E0155] On Market
Our assessment
The evidence shows that Kirkland Signature Ultra Strength Antacid Calcium Carbonate 1000 mg is a straightforward calcium supplement. Our assessment: for most people, this product can effectively support your daily calcium needs, but you must be careful about your total calcium intake from all sources to avoid exceeding safe upper limits [NIH ODS].
How it works
Think of calcium as the structural building block for your bones. This product provides 1000 mg of calcium carbonate, which works through two key mechanisms: bone mineralization to support bone density and mineral deposition, and neuromuscular relaxation to support proper muscle and nerve signaling [NIH ODS].
Safety profile
The FDA has received 592,059 total adverse event reports across all calcium products, though data specific to this brand is not available [FDA data]. You should be aware that very high calcium intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in your blood and urine can cause poor muscle tone, poor kidney function, low phosphate levels, constipation, nausea, weight loss, extreme tiredness, frequent need to urinate, abnormal heart rhythms, and a high risk of death from heart disease [NIH ODS].
Our recommendation
We recommend you start by evaluating your total daily calcium intake from food and other supplements. Since this product provides 1000 mg per serving, you should not take additional calcium supplements unless advised by your doctor. Be aware that calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin — take this supplement at least two hours apart from these medications [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | Kirkland Signature |
|---|---|
| Serving Size | |
| Contents | 265.0 Tablet(s) |
| Market Status | On Market |
How to Read This Label
Supplement labels contain several key sections regulated by the FDA:
- Serving Size — The recommended amount per dose. Always check this — some products require multiple capsules per serving.
- Amount Per Serving — Shows the quantity of each nutrient in the product, typically in IU (International Units), mg (milligrams), or mcg (micrograms).
- % Daily Value (%DV) — Indicates how much a nutrient in a serving contributes to a daily diet. 5% DV or less is low; 20% DV or more is high.
- Other Ingredients — Lists inactive ingredients like fillers, binders, and capsule materials (e.g., gelatin, cellulose, magnesium stearate).
- Suggested Use — The manufacturer's recommended directions for taking the supplement, including timing and dosage.
Source: FDA Dietary Supplement Labeling Guide