Over the past 30 years I have taken hundreds and thousands of people off garlic due to its irritating effect. It has a definite detrimental effect on brain performance and blood vessel health.
In the 6,000-year old medical system of Ayurveda, garlic is not considered a food, but a toxic substance. Its mental effects are known as rajas, a source of irritability, anger, agression, confusion, reduced concentration and mental stability. Furthermore, it it irritates the mucus-ling of the GI-tract and can burn the insides. Ayurveda puts onions in the same category. For this reason, there is no authentic Ayurvedic recipe that includes onion and garlic.
According to recent studies, there is no evidence whatsoever, that garlic has any health benfits.