It's the most wonderful time of the year. This is the time to be jolly and attend parties and celebrations everywhere. However, it is also known that during this time, people tend to overeat. Is there really a science as to why people overeat during the holidays? What happens when people have eaten too much? During the holidays, it's a little hard to say no after a three course meal just because you are in the company of your family and loved ones. An article in Good Food asked the same question. They asked questions such as, how much is the total capacity of the stomach? How much food can be consumed in order to induce nausea or stomach straining?

According to Nova, a science website and the Australian Academy of Science said that the capacity of the human stomach is not as great we may think. On average, an adult stomach can comfortably hold about one litre of food and drinks, anything more than that can make the stomach uncomfortable. The human body is flexible. Brooke Harcourt, Nutritionist and childhood obesity researcher from the Murdoch Childrens Research Institute said that a calm stomach cavity has a size of a fist, and then food enters the stomach, it can stretch to hold up to four litres of food and drinks.

When someone overeats, the uncomfortable feeling is caused by the stomach pressing in the other organs like the liver diaphragm and lungs. Dr Harcourt said, "In a bad case it can inhibit their function a little bit, so it gets harder to breathe which is why people loosen that top button. As it starts to expand we get what we sometimes refer to as a 'food baby'." Anything more than 4 litres of food and drink in the stomach can start a gag reflex, the digestive system goes into reverse and you end up vomiting. The gag reflex is triggered not only by the too much food in the stomach but also because the acidity level is elevated as it aids in the digestion.

In this case, heartburn can also be triggered and not to mention, burping as the body tried its best to get rid of the unwanted air that was ingested during eating.

Finally, in order to avoid overeating, Dr. Harcourt said that you should listen to your body.  She said, "You can also have a glass of water before the meal, so you are already feeling a little full. The water also gets the digestion process going."  She added that 80 percent of the time when people think they are hungry, they are actually thirsty.