21st Century Daily Amino Acid
Brand: 21st Century · Form: TABLET [E0155] On Market
Our assessment
The evidence shows that 21st Century Daily Amino Acid is a supplement containing calcium, a mineral essential for bone health. However, our assessment is that the specific benefits of this product depend entirely on your individual calcium needs. For most adults, the primary role of calcium is to support bone density and mineralization, as well as neuromuscular signaling [NIH ODS].
How it works
Think of calcium as a building block for your skeleton. It works through two main mechanisms: bone mineralization, which helps deposit minerals into your bones to keep them strong, and neuromuscular relaxation, which supports proper muscle and nerve signaling [NIH ODS].
Safety profile
FDA received a total of 592,059 adverse event reports for all products, with data for this specific product stating "Data not available." For calcium specifically, 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]. Calcium can also reduce absorption of bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Our recommendation is to assess your dietary calcium intake before adding this supplement. Most adults need 1,000 to 1,200 mg of calcium daily from all sources. Do not exceed the tolerable upper intake level. Always take calcium supplements with food and separate from medications like thyroid hormone or antibiotics by at least 2 hours [NIH ODS]. Consult your healthcare provider to determine if this supplement is right for you.
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | 21st Century |
|---|---|
| Serving Size | |
| Contents | 120.0 Tablet(s) |
| Market Status | On Market |
How to Read This Label
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