Nature's Sunshine Magnesium

Our assessment

The evidence shows that calcium—the key ingredient in this supplement—plays a vital role in your body, but it comes with important safety considerations. Based on the data, you should approach this supplement with caution, particularly if you have a history of kidney issues or heart disease. The exact dosage and formulation of this specific product are not available in the data provided, so we cannot confirm the precise amount of calcium you would be taking.

How it works

Calcium is a mineral that acts as a master regulator for your bones and nerves. It supports bone density and mineral deposition through a process called bone mineralization, and it also helps your muscles relax and your nerves send signals properly [NIH ODS]. Think of it as the structural scaffolding for your skeleton and the quiet conductor of your nervous system.

Safety profile

The FDA received a total of 592,059 adverse event reports across all supplements, though the number specific to this product is not available. The data shows that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. Side effects from high levels include 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]. Calcium can also reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

Because the data for this specific product is incomplete—the brand and exact calcium dosage are listed as "See label"—we cannot offer a precise dosing recommendation. You should consult your healthcare provider before starting this supplement, especially if you take any of the medications listed above. If you choose to use it, check the product label carefully for the exact amount of calcium per serving and do not exceed the recommended daily allowance without medical 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