on September 29, 2026
Stroke is one of the leading causes of acquired disability in adults. Brain injury caused by interrupted or markedly reduced blood flow, or by the rupture of a blood vessel, can leave consequences affecting movement, language, attention, memory, balance, autonomy, and the ability to perform normal daily activities.
Recovery does not coincide with the simple healing of the initial injury. It is the result of a dynamic process involving neuroplasticity, reorganization of neural networks, motor and cognitive relearning, functional adaptation, and active participation in rehabilitation. For this reason, the post-stroke journey generally requires a multidisciplinary approach in which neurology, physiatry, physiotherapy, occupational therapy, speech therapy, nutrition, and management of cardiovascular risk factors may converge.
In this context, scientific interest has also developed towards certain substances of plant origin traditionally used in various medicines. The hypothesis is not to replace rehabilitation or conventional therapies, but to verify whether some bioactive compounds can interfere with biological processes potentially relevant to neurological function, such as oxidative stress, inflammation, neuronal energy metabolism, synaptic plasticity, and vascular function.
A recent systematic review with network meta-analysis published in 2025 collected precisely this evidence. 48 randomized clinical trials were analyzed, involving a total of 6,599 patients affected by stroke. The research considered nine different plant extracts: Ginkgo biloba, ginsenosides derived from ginseng, berberine, Hypericum perforatum extract, resveratrol, gastrodin, Crocus sativus, Moringa oleifera seed extract, and Panax notoginseng saponins.
The authors considered several scales used in neurological and functional assessment after stroke: National Institutes of Health Stroke Scale (NIHSS), Modified Rankin Scale (mRS), Activities of Daily Living (ADL), Barthel Index, Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA).
The meaning of cognitive function in post-stroke recovery
Recovery after a stroke does not only concern the ability to walk or use a limb. Memory, attention, processing speed, language, and executive abilities can profoundly condition the patient's autonomy and their participation in the rehabilitation program.
A reduction in cognitive function can indeed make it more difficult to learn new motor patterns, correctly perform exercises, manage daily activities, and adhere to therapeutic indications.
For this reason, cognitive assessment through standardized tools such as MMSE and MoCA represents an important element in monitoring recovery.
The 2025 network meta-analysis observed favorable signals for some extracts. Hypericum extracts obtained the highest relative probability of reduction in NIHSS scores and improvement in activities of daily living, while berberine showed the highest SUCRA value for the Modified Rankin Scale. Ginsenosides, on the other hand, showed the highest relative probabilities for improvement in the Barthel Index, MMSE, and MoCA.
However, it is important to correctly understand the meaning of these results. The SUCRA value allows for the probabilistic ordering of interventions within the network meta-analysis, but it does not equate to demonstrating that a given extract is clinically superior to a standard rehabilitation or pharmacological therapy. Furthermore, the included studies presented differences in the preparations used, dosages, patient characteristics, and methodological quality.
The same authors highlighted the presence of heterogeneity and the need for larger studies, with longer follow-ups and greater methodological rigor, as well as the need to clarify the role of dose and external factors, including social support.
Why plants interest neurological research
Interest in botanicals derives partly from their biochemical complexity. Many extracts simultaneously contain flavonoids, terpenes, polyphenols, saponins, or other compounds capable of interacting with different cellular pathways.
In the context of cerebral ischemia, some of the most studied mechanisms include redox balance, inflammatory response, endothelial and mitochondrial function, regulation of cell death, and neuronal plasticity.
These mechanisms are biologically plausible, but molecular plausibility must not be confused with clinical efficacy. A compound that exerts an antioxidant effect in a cellular or animal model does not automatically demonstrate that it improves neurological recovery in a human being.
The distance between biological mechanism and clinical benefit is particularly important in neurology, where the complexity of brain networks makes it difficult to attribute an isolated therapeutic effect to a single compound.
Hypericum: an interesting but clinically delicate result
Hypericum (Hypericum perforatum) is probably one of the most interesting elements that emerged from the network meta-analysis, because it obtained favorable relative values for NIHSS and activities of daily living.
However, this data must be interpreted with particular caution.
Hypericum has important pharmacological activity and can alter the metabolism of numerous medications through the induction of enzymatic systems and transporters. In a post-stroke patient, who may take antiplatelets, anticoagulants, cardiovascular medications, or other chronic therapies, this represents a priority safety element.
Therefore, the meta-analysis result does not constitute a recommendation for self-medication with hypericum. On the contrary, it shows how important it is that any future studies are accompanied by a rigorous assessment of pharmacological interactions.
Saffron, resveratrol, and other botanicals
Crocus sativus, resveratrol, gastrodin, Moringa oleifera, and Panax notoginseng were also included in the review.
These substances present different biological profiles. Some have been studied mainly for their antioxidant and anti-inflammatory properties, others for vascular function or possible effects on the central nervous system.
Scientific interest is therefore real, but the heterogeneity of preparations constitutes a relevant problem. It is not enough to establish that a plant contains a certain active principle: it is necessary to know the titration, the composition of the extract, the dose actually used in the studies, and the method of administration.
This principle is fundamental in modern phytotherapy: plant, extract, and active principle are not necessarily equivalent.
Ginkgo biloba and brain function
Ginkgo biloba is one of the most studied plant extracts in the neurovascular and cognitive field. Its main bioactive compounds include flavonoids and terpenoids, studied for their interactions with oxidative stress, endothelial function, cellular metabolism, and neuronal signaling.
In the context of stroke, however, the available studies do not allow for Ginkgo biloba to be considered a replacement therapy. Its presence in the network meta-analysis indicates that there is concrete clinical interest, but it does not allow the automatic transfer of results from a standardized preparation to any product containing ginkgo.
Another particularly important aspect concerns pharmacological interactions. Patients who have had a stroke frequently have antiplatelet, anticoagulant, antihypertensive, and lipid-lowering therapies. The eventual use of botanicals must therefore be evaluated individually by the doctor.
Ginsenosides and neuronal metabolism
Ginsenosides are saponins characteristic of the Panax genus. They have been studied for their possible influence on energy metabolism, oxidative stress, neuroinflammation, vascular function, and neuronal plasticity.
In the network meta-analysis, ginsenosides showed the most favorable relative results for some measures of cognitive function and autonomy, in particular MMSE, MoCA, and Barthel Index.
The data is interesting because it suggests that some plant compounds could be studied not only in relation to motor deficit, but also regarding the cognitive and functional dimensions of recovery.
In this case, however, it is also necessary to distinguish between the aggregated result of the research and individual clinical use. Extract preparation, concentration of active principles, dose, duration, and patient characteristics can significantly alter the result.
Berberine, metabolism, and neurological recovery
Berberine is a plant alkaloid studied mainly in relation to glucose and lipid metabolism, mitochondrial function, inflammatory response, and oxidative stress.
In the network meta-analysis, it obtained the highest relative probability of improvement in the Modified Rankin Scale.
However, this result must not be interpreted as definitive proof of an anti-disability effect. The Modified Rankin Scale is a global measure of functional outcome, and the result of a network meta-analysis depends on the overall structure of the available comparisons.
Berberine is also pharmacologically active and can interact with medications and metabolic systems. In patients taking multiple medications, a frequent situation after a stroke, professional assessment is particularly important.
The role of rehabilitation remains central
The presence of encouraging results in botanical research does not change the central role of rehabilitation.
Neuroplasticity depends on experience, repetition, and learning. Physiotherapy, occupational therapy, speech therapy, and cognitive rehabilitation are fundamental tools to stimulate functional recovery.
No plant extract can replace the repetition of a motor gesture, balance training, language retraining, or personalized cognitive work.
Botanical research may eventually contribute to building integrated strategies in the future, but these will need to be validated through adequately designed clinical trials.
Nutrition, metabolism, and recovery capacity
Another often underestimated element in the post-stroke journey is nutritional status.
Recovery requires energy, protein synthesis, micronutrients, adequate muscle function, and the ability to sustain repeated rehabilitation programs. A nutritional deficiency can therefore represent an additional factor of vulnerability.
Among micronutrients, iron deserves particular attention.
Iron is essential for oxygen transport through hemoglobin, but it is also involved in mitochondrial energy production, DNA and neurotransmitter synthesis, and myelin formation. The brain therefore presents a strictly regulated iron metabolism.
An iron deficiency does not necessarily coincide with anemia. The reduction of iron stores can precede the decrease in hemoglobin and can be associated with fatigue, reduced physical capacity, and cognitive performance alterations.
A particularly interesting aspect for recovery after stroke emerges from an observational study conducted on 746 patients in early rehabilitation. Iron deficiency was present in 45% of patients at admission and remained present in 40% at discharge; both iron deficiency and anemia were associated with lower functional capacity and a worse rehabilitation outcome.
However, this study is observational. It demonstrates an association, not that the administration of iron necessarily improves neurological recovery.
The authors themselves emphasize the need for further studies to establish whether the correction of iron deficiency can increase functional capacity and the effectiveness of rehabilitation programs.
Iron and cognitive function
The relationship between iron and the brain is particularly complex. Iron is necessary for neuronal energy metabolism, neurotransmitter synthesis, and myelin production, but excess iron can also be harmful through oxidative mechanisms. The physiological goal is therefore not to indiscriminately increase iron, but to maintain the micronutrient's homeostasis.
Clinical studies have observed associations between iron status and cognitive performance. In young women, an interventional study highlighted a relationship between improvement in iron stores and improvement in cognitive performance, while other studies showed the effect of iron supplementation on fatigue in menstruating women with low ferritin but without anemia.
This evidence does not mean that iron constitutes a cognitive or neurological therapy. Rather, it indicates that the correction of a documented deficiency can be important for maintaining normal brain and systemic physiology.
An integrated, but evidence-based approach
Contemporary research on post-stroke recovery is progressively expanding its attention from the brain injury alone to the person as a whole.
Neuroplasticity, rehabilitation, adapted physical activity, nutrition, sleep quality, cardiovascular health, metabolism, and psychological support represent interconnected components of the recovery journey.
Plant extracts may constitute an interesting field of complementary research. The 2025 review offers preliminary signals, especially for St. John's wort, berberine, and ginsenosides, but simultaneously highlights the heterogeneity of the evidence and the need for more robust clinical studies.
The same caution must be applied to nutrition: a documented iron deficiency deserves attention, especially because in the post-stroke patient it may be associated with a reduced functional capacity. However, before supplementing with iron, it is advisable to know the iron status through appropriate tests and to evaluate the cause of the deficiency with a doctor.
In this perspective, the concept of “natural” cannot be used as a synonym for “safe” or “therapeutic”. A plant extract can have a powerful biological activity and interact with medications. Similarly, an essential micronutrient can be useful when deficient but should not be taken indiscriminately.
The future of research will therefore probably be oriented not toward replacing conventional medicine with natural remedies, but toward building integrated, personalized, and documented strategies, in which each intervention is evaluated for efficacy, safety, dose, and clinical appropriateness.
Main reference
Li J, Jin J, Cheng Y, Zhang Y, Wang X, Chen Y, Wang C, Tang W, Zhang N. Systematic Review and Network Meta-Analysis of the Effects of Plant Extracts on Cognitive Function and Quality of Life in Stroke Patients. Phytotherapy Research. 2025;39(5):2110-2130. DOI: 10.1002/ptr.8472. The review included 48 randomized trials and 6,599 patients.
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