Religous tolerance is produced when people are interested in the truth. Religious intolerance is produced when people find it difficult to acknowledge the truth usually for personal reasons e.g. when their own lifestyle, their children's lifestyle, their associates lifestyle etc contradict the truth.
It can be for a number of reasons. If it is milk chocolate, and you have a lactose intolerance, it can cause irritation. Some people also have issues with large amounts of sugar.
Many people eat "starburst" candy with no issues to their stomach. It's possible you have an intolerance to an ingredient in them such as Red Dye #40, etc.
The cause was racial intolerance.
Since the cause of the enzyme deficiency leading to carbohydrate intolerance is unknown, there is no way to prevent this condition.
YES, you might have a milk intolerance.
Cause they want to change there attitudes
The first cause of food intolerance associated with the what you eat or the way you eat is eating too much of the same food too often. The next cause of food intolerance associated with what you eat or the way you eat is eating too many foods that contain additives, preservatives colouring agents and flavour enhancers.
Hate and intolerance begets violence and murder.
During the period of time between 1840 and 1850, the Protestant religions comprised 95% of the US population. The increase of Catholic immigrants, mostly from Ireland caused that percentage to drop to 90%. That figure is still massive, however, the ethnic and religious intolerance did cause a push back by many nativists. One clear example of US ethnic and religious intolerance raised its ugly head in the Mexican War. There Irish US soldiers deserted to join Santa Ana. He reminded these soldiers that Irish people were not well likes in the US and he offered them land to desert the US army.
The causes are the usual ones for discrimination: intolerance, lack of understanding, and fear. The effects are also the usual ones: people get hurt by other people, or have fewer rights, or violence can break out.
Lactose is a simple carbohydrate and typically is the reason for milk intolerance in people. Lactose is a simple sugar/carbohydrate.
Watermelon can cause diarrhea (and/or abdominal pain and bloating), if you have an intolerance or allergy to watermelon.