Nobody seems to actually know the exact reasons that could be directly linked to colic. Some say that infants who have more sensitive guts are more likely to deal with this specific issue. Others say that it could be related to the mother’s diet. Finally, lactose intolerance could be another reason. Either way, here are some of the most common colic symptoms that you should be aware of: • Recurring episodes of intense crying that occur mostly in the evening; • Gassy and tight tummy; • Red flushed face; • Arched backs and clenched fists.