Nutraceutical Sciences Institute Calcium Magnesium & Vitamin D

Our assessment

The evidence shows that this combination supplement provides calcium, magnesium, and vitamin D, which support bone health. However, you need to be cautious with calcium dosing, as high intakes carry significant risks. Data not available for the specific amounts of each ingredient in this product, so we cannot verify the exact potency [NIH ODS].

How it works

Think of this trio as a team for your skeleton. Calcium is the primary mineral for bone mineralization and density, while magnesium supports neuromuscular relaxation and nerve signaling. Vitamin D helps your body absorb calcium efficiently [NIH ODS].

Safety profile

FDA received 592,059 total adverse event reports for products in this category. For calcium specifically, high intakes might increase the risk of heart disease and prostate cancer. High levels in the blood and urine can cause poor muscle tone, poor kidney function, low phosphate levels, constipation, nausea, weight loss, extreme tiredness, frequent urination, abnormal heart rhythms, and a high risk of death from heart disease [FDA data] [NIH ODS].

Our recommendation

Start by checking your dietary calcium intake from food first. If you choose this supplement, take it with food and separate it from medications like bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin by at least 2 hours to avoid absorption problems [NIH ODS]. Do not exceed the Tolerable Upper Intake Level without medical supervision. Data not available on the exact label amounts, so verify the dose per serving before use [NIH ODS].

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