Can the degree of synaptic plasticity be altered by environmental factors such as diet and exercise?
There is no neuroscience based research supporting any supplements, but good news is that unless someone is very deprived of basic nutrition, the brain will throughout life respond with neuroplastic boosting of any neural networks e.g. memory or skills that are ACTIVATED. It is simply the activation of the set of neurons connected together holding the information that activates the neuroplastic construction - more dendrite connections and myelin. You can read about cognitive reserve (no supplements needed) as a potential benefit reducing the impact of degenerative neural diseases such as those associated with Alzheimers.