ProCaps Laboratories Vitamin D3 4000

Our assessment

The evidence shows that this product provides 4000 IU of vitamin D3 per serving. Based on the data provided, vitamin D is a well-studied supplement, but the specific safety and efficacy data for this exact product at this dose is data not available. The key ingredient in this supplement is calcium, not vitamin D, according to the data provided. For calcium, the National Institutes of Health Office of Dietary Supplements notes that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS].

How it works

Think of calcium as a structural building block for your bones. It supports bone mineralization and density, and also plays a role in neuromuscular relaxation and nerve signaling [NIH ODS].

Safety profile

The FDA has received 592,059 total adverse event reports for all dietary supplements. For calcium specifically, high intakes can lead to constipation, nausea, weight loss, extreme tiredness, frequent need to urinate, and abnormal heart rhythms. High levels in the blood and urine can also cause poor muscle tone, poor kidney function, low phosphate levels, and a high risk of death from heart disease [NIH ODS]. Calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

Data not available on the specific health benefits or risks of this exact product at this dose. Because the data provided focuses on calcium rather than vitamin D, you should consult your healthcare provider before starting this supplement, especially if you take any of the medications that interact with calcium. Your provider can help you determine if this dose is right for you [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