The goal of this interventional study is to to evaluate the oral bioavailability of the crystallized form of pterostilbene (ccPT) compared to its commercial free base form (pterostilbene (PT) in healthy volunteers. The main question it aims to answer are:

• Do the crystallized forms of pterostilbene (ccPT) using two different encapsulation methods exhibit greater bioavailability than its commercial free base form (PT)?

Participants will attend to four visits: a preselection visit (V0), a visit for the first postprandial study (V1), a visit for the second postprandial study (V2) after one-week washing period and a visit for the third postprandial study (V3) after another one week washing period.

Researchers will analyze the three postprandial assays to determine which type of ccPT encapsulation provides the highest bioavailability compared to the commercial free base form (PT).

The oxidative stress (OS) is a condition where pro-oxidative processes overwhelm cellular antioxidant defenses due to disruption in redox signaling. This results in the body's inability to eliminate reactive oxygen species (ROS) or repair damages, potentially leading to severe impacts on cells, tissues, and organs.

Pterostilbene (PT) is a stilbenoid found in various natural sources, emerging as an antioxidant with potential preventive and therapeutic properties in numerous diseases. Despite its promising properties, PT's low water solubility and bioavailability pose challenges.

Nutraceutical co-crystallization is a recent strategy to enhance solubility and oral bioavailability. It has been identified that a new pterostilbene:picolinic acid (1:1) co-crystal, significantly increasing solubility and oral bioavailability compared to commercial free base PT.

The study aims to evaluate oral bioavailability (AUC0-24h) of PT (free and total) from ccPT compared to commercial PT, using two different encapsulation methods. Secondary objectives include determining pharmacokinetic parameters such as AUCinf, relative oral bioavailability (Frel), Cmax, Tmax, and T1/2 for both free and total PT.

This randomized, crossover, single-blind clinical trial aims to provide insights into the effectiveness of the new ccPT formulation in enhancing PT's oral bioavailability compared to the commercial PT formulation.

Inclusion Criteria:

• Men and women between 18 and 65 years of age.
• Sign the informed consent form.
• Know how to read, write and speak Spanish

Exclusion Criteria:

• Take supplements or multivitamin supplements or phytotherapeutic products (especially infusions) that interfere with the treatment under study up to 30 days before the start of the study.
• Be lacto-vegetarian, lacto-ovo-vegetarian, or vegan.
• Present intolerances and/or food allergies related to pterostilbene or the excipients.
• Be a smoker.
• Having received antibiotic treatment up to 30 days before the start of the study.
• Present values of body mass index ≤ 18kg/m^2 or ≥ 35 kg/m^2.
• Present some chronic disease with clinical manifestations: coronary heart disease, cardiovascular disease, diabetes, celiac disease, Crohn's disease, chronic kidney disease, cancer, autoimmune diseases (such as fibromyalgia), respiratory and/or gastrointestinal diseases that may compromise the absorption of the compound.
• Clinical history of anemia.
• Being pregnant or intending to became pregnant.
• Be in breastfeeding period.
• Being unable to follow the study guidelines.
• Participate in or have participated in a clinical trial or nutritional intervention study in the last 30 days before inclusion in the study.

In this study IPD will not be shared with other researchers because all the information will be processed by the UTNS of Eurecat.