Extracts from the ashwagandha plant, especially withanolides, work in a variety of ways in the body. They seem to have a neuro-protective impact on the brain which helps with memory retention and cognitive function while also calming the mind and reducing anxiety. The herb seems to reduce inflammation in the body, which may protect you from a host of illnesses, including heart disease and cancer. The chemicals in ashwagandha also seem to reduce blood pressure and create positive changes to the immune system, according to the National Institutes of Health.