SQUARE MEAL AND TRENCH MOUTH
People with money had plates made of pewter. Food with a high acid content caused some of the lead to leach onto the food causing food poisoning. This happened most often with tomatoes, so for a long time, tomatoes were considered poisonous.
Most people did not have pewter platers; rather a piece of wood with the middle scooped out like a bowl. This was called a trencher. Sometimes the trenchers were made from stale bread which was so old and hard that they could be used for quite some time. Trenchers were rarely washed and at times worms and mold got into the wood and old bread. After eating food off wormy, moldy trenchers, one might get a mouth infection which came to be known as TRENCH MOUTH.
Some trenchers were in the shape of a square. The main dinner meal would be eaten on one side of the square trencher. Some sort of cheese and bread or a dessert would be served on the other side of the trencher. Usually, these food varieties were served in wealthier households.This SQUARE MEAL came to be associated with the concept of a well-balanced dinner.