Major Calcium 600 mg

Our assessment

The evidence shows that calcium is a foundational mineral for bone health, but it is not without risks. For the product Major Calcium 600 mg, our assessment is that it can be an effective tool to help you meet your daily needs, but you must be careful about your total intake from all sources. The National Institutes of Health notes that calcium supports bone mineralization and neuromuscular relaxation [NIH ODS].

How it works

Think of calcium as a structural building block for your skeleton and a key signaling molecule for your nerves and muscles. It works by supporting bone density and mineral deposition, and it helps your muscles relax and your nerves send signals properly [NIH ODS]. Without enough calcium, your body will leach it from your bones, which can weaken them over time.

Safety profile

The FDA has received a total of 592,059 adverse event reports across all supplements, though this number is not specific to calcium alone. For calcium specifically, high intakes can cause constipation, nausea, and weight loss. More seriously, consistently high levels of calcium in the blood and urine can lead to poor kidney function, abnormal heart rhythms, and an increased risk of death from heart disease [NIH ODS]. Some research also suggests high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. Additionally, calcium can reduce the absorption of medications such as bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

Start by calculating your total daily calcium intake from food and other supplements. If you are already getting 800–1,000 mg from your diet, a 600 mg supplement may push you into a range associated with risks. We recommend taking this supplement with food to improve absorption, and never taking it at the same time as thyroid medication or certain antibiotics. For most adults, the goal is a total of 1,000–1,200 mg per day from all sources, but do not exceed that without a doctor's guidance [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