As previously described here, turmeric has antioxidant, antimicrobial, and anti-inflammatory properties leading to improved immune response. In in vivo experiments to study graft-versus-host disease (induced after bone marrow transplantation), mice were pretreated with curcumin (100 µg/mouse). These curcumin-pretreated mice showed an increase in CD4+ and CD8+ cells before the transplant, preventing the disease 
. Jian et al. studied the effects of curcumin as a dietary supplement in the male Hu sheep model, reporting changes in blood metabolites, antioxidant capacity, testicular development, and immune response. After four months of dietary supplementation, the sheep improved their reproductive system performance 
. In vivo and clinical studies indicate that curcumin can positively affect several immune cells (i.e., T lymphocyte subsets, macrophages, dendritic cells, B lymphocytes, and natural killer cells), which diminishes the severity of different autoimmune diseases 
. Additional studies found promising results in patients with several pro-inflammatory illnesses (i.e., cardiovascular disease, renal diseases, arthritis, Crohn’s disease, ulcerative colitis, irritable bowel disease, pancreatitis, peptic ulcer, gastric ulcer, oral lichen planus, vitiligo, psoriasis, acute coronary syndrome, atherosclerosis, diabetes, lupus, acquired immunodeficiency syndrome, β-thalassemia, biliary dyskinesia, and Dejerine-Sottas disease) 
. Most recently, a study showed that curcumin supports immunomodulatory responses by inhibiting the cell-mediated response of inflammatory cytokines and, thus, mitigating progression to pneumonia and acute respiratory distress syndrome (ARDS) after SARS-CoV-2 infection 
3.6. Predicted gastrointestinal (GI) absorption
The physicochemical properties for the main four most bioactive phytochemicals in turmeric (curcumin, demethoxycurcumin, bisdemethoxycurcumin and α-turmerone) were calculated based on the combination of Lipinski’s, Ghose’s, and Veber’s rules (L-Ro5, GF, VR), summarized as follow: molecular weight (160-500 Da); hydrogen bond donors ≤5; hydrogen bond acceptors ≤10; molar refractivity (40-130); lipophilicity (-0.4–5.6); rotatable bonds ≤ 10: polar surface area <140; total number of atoms (20-70) ,,,. These are described as an approximation for the pharmacokinetics of a molecule in the body. From turmeric’s phytochemicals, 100% (curcumin, demethoxycurcumin, bisdemethoxycurcumin and α-turmerone) comply with all of the “drug-likeness” rules. Accordingly, all these turmeric’s phytochemicals are predicted to show high probability of absorption in the GI.