Nature's Way Prenatal Multi Vitamin & Mineral

Our assessment

The evidence shows that the calcium in this prenatal multi is important for your health and your baby's development, but it comes with specific safety considerations you need to know about. Our assessment is that this supplement is likely safe when taken as directed, but you must be aware of potential medication interactions and the risks of excessive intake [NIH ODS].

How it works

Calcium plays two critical roles during pregnancy. First, it supports bone mineralization for your developing baby, helping to build strong bones and teeth. Second, it supports neuromuscular relaxation, which helps your muscles relax and nerves signal properly — a key function as your body changes [NIH ODS]. Think of calcium as the structural foundation and the calming signal for your body's systems.

Safety profile

FDA received a total of 592,059 adverse event reports for this product. While high calcium intakes are generally safe, some research suggests that very high 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]. Critically, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

Take this prenatal multi exactly as directed on the label. To maximize absorption and minimize side effects, take it with food. If you take any prescription medications — especially thyroid medication, antibiotics, or bone drugs — separate your supplement from those medications by at least 2 hours [NIH ODS]. If you have a history of kidney stones, heart disease, or high calcium levels, consult your healthcare provider before starting. Do not take additional calcium supplements unless your doctor specifically recommends it [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