I purchased this brand of grape seed extract because NOW has a good reputation, but there are other companies I have used for this supplement who also have a good reputation, including Life Extension and Solgar. There is no current daily recommended dosage of grape seed extract, but scientific studies have used dosages of 100-300 mg./day to produce a therapeutic result with no negative side effects. This brand is within that range at 200 mg. per capsule. Research has found that grape seeds contain natural compounds that are antibacterial, antiviral, anti-inflammatory, and anti-allergic (that is, they can help heal a tendency to allergies). They also contain powerful antioxidants which research for many years has found to prevent or help heal the following health conditions: leg edema and lymphedema (massive swelling of an arm or leg, commonly caused by the removal of or damage to lymph nodes as a part of cancer treatment), arthritis, dental decay, Hemorrhoids, osteopenia and osteoporosis, heart disease, diabetes, Alzheimer's, and cancer. The anti-cancer effect of grape seed extract is due to the fact that it promotes apoptosis (cell death) among otherwise "immortal" cancer cells, and it also contains high levels of compounds that are aromatase inhibitors. Aromatase is an enzyme that converts androgen to estrogen, a proliferative hormone that encourages the growth of cancer cells, especially in breast tissue