The lutein to zeaxanthin ratio in the complete formulation is 5:1; this is an optimum ratio taken into account in clinical studies and recommended globally.

The coat of the internal capsule contains fish gellatin, so this dietary supplement is not recommended for vegans.

Please note that clinical trials are linked with numerous raw ingredients used in the composition of our products, butnot the products themselves.

In case of DuoLife Clinical Formula ProOptical®, such trials were conducted for lutein and zeaxanthin formula. The lutein and zeaxanthin formula used in the preparation is the most researched lutein and zeaxanthin form obtained in a patented process, with its effectiveness backed by over 70 various clinical trials conducted worldwide by, i.a., the prestigious National Institutes of Health (NIH) or National Eye Institute (NEI). Collectively, these trials cover a wide range of clinical parameters, from the amount of obtained lutein bioavailability to the precise, measurable score, including cognitive functions improvement. The formula of lutein and zeaxanthin used in the product constitutes this form of a raw ingredient that is most often investigated by the researchers and recommended by doctors worldwide.

Taking ProOptical has not been shown to affect driving skills.

DuoLife Clinical Formula ProOptical® dietary supplement can be used in children over 12 years of age.

In case of pregnant and breastfeeding women, an attending physician decides about any supplementation. A woman's body during this period has specific needs; therefore individual approach and consulting your attending physician is key. Checking and defining the body's needs is necessary. Basing on interview and test results, the attending physician is able to determine which nutrients - and at what doses - are needed by a given person.