Natural Factors Whole Earth & Sea Women's Multivitamin & Mineral

Our assessment

The evidence shows that this product provides a foundational level of calcium, a mineral essential for bone health and nerve function. However, it is important to understand the specific benefits and risks associated with this ingredient. Our assessment: the calcium in this multivitamin can support your bone density, but you should be aware of potential interactions and safety limits.

How it works

Think of calcium as a building block for your bones and a signal regulator for your nerves and muscles. It works by supporting bone mineralization, which is the process of depositing minerals into your bone tissue for strength. It also supports neuromuscular relaxation, helping your muscles relax and your nerves send signals properly [NIH ODS].

Safety profile

Data on this specific product's side effects is limited. However, for calcium in general, the FDA has received a total of 592,059 adverse event reports across all supplements. 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]. Some research also suggests that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS].

Our recommendation

You can take this multivitamin as part of a balanced diet, but do not rely on it as your sole source of calcium. Be cautious about taking additional calcium supplements, as exceeding recommended levels increases the risks mentioned above. Also, calcium can reduce the absorption of medications like bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS]. If you take any of these medications, separate your doses by at least two hours. For personalized advice, consult your healthcare provider.

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