Nature's Bounty Coral Calcium Plus Vitamin D3 & Magnesium

Our assessment

The evidence shows that this combination supplement provides calcium, vitamin D3, and magnesium to support bone health. Our assessment is that while these nutrients are essential, you should be aware of specific safety considerations before starting supplementation.

How it works

Think of this supplement as supporting your skeletal foundation. Calcium is vital for bone mineralization and neuromuscular relaxation, helping your muscles relax and nerves signal properly [NIH ODS]. Vitamin D3 helps your body absorb that calcium, while magnesium supports the activation of vitamin D.

Safety profile

FDA has received a total of 592,059 adverse event reports for calcium-containing products. Key safety data shows that high calcium intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in the 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]. Additionally, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

Start by evaluating your current dietary calcium intake from food sources. If you take other medications, separate calcium supplements by at least two hours to avoid absorption interference. Data not available for specific dosage recommendations for this product. We recommend discussing this supplement with your healthcare provider, especially if you have a history of kidney stones or heart conditions [NIH ODS] [FDA data].

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