NOW Sports Branched Chain Amino Acid Powder

Our assessment

The evidence shows that this product delivers branched chain amino acids, but the primary ingredient with available safety data is calcium. For general health, you should be aware that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. Because specific data for this product's main intended effects is limited, our assessment is that you should focus on the calcium content and its potential risks.

How it works

Calcium supports bone mineralization and neuromuscular relaxation, meaning it helps your bones stay dense and your muscles relax properly after contracting [NIH ODS]. Think of it as a structural supporter for your skeleton and a signal regulator for your nerves and muscles [NIH ODS]. The role of the branched chain amino acids in this powder is not detailed in the provided data.

Safety profile

FDA received 592,059 total adverse event reports across all supplements [FDA data]. For calcium specifically, high levels in your 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]. Additionally, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].

Our recommendation

We recommend you speak with your healthcare provider before using this product, especially if you take any medications listed above. Because high calcium intakes carry significant risks, you should not exceed the recommended serving on the label. Data not available for the specific benefits or side effects of the branched chain amino acids themselves in this product. Your safest approach is to prioritize dietary sources and confirm with your doctor that supplementation is appropriate 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