All cultures have various traditional beliefs and customs concerning food. Sometimes people eat special foods at festivals. Some foods may be avoided on particular days. Foods that are avoided in one culture may be valued in another. Some foods may be forbidden completely in certain cultures or religious groups but enjoyed in others.
Most of these beliefs have little impact on nutrition but there are some that have a large impact. For example, in many cultures pregnant or nursing women are not supposed to eat eggs. However, eggs are a very nutritious food. Children may also be prevented from eating foods that would be of real nutritional benefit.
Changing unhelpful food customs is difficult to do and can take a lot of time.