During the Wu period, yang qi reaches its peak. Since it can assist the spleen in transportation and transformation, phlegm is unlikely to be produced if one has lunch at this time. But food intake after the Wu period will become relatively difficult to digest and phlegm is easily produced, because yang qi gradually declines, and "fire (heart) fails to warm the earth (spleen)". The principle of lunch is to "eat well", but it doesn't mean to eat a large amount of fish and meat or other foods, but to have a balanced meal. This should include staple food, food with rich protein, vegetables and fruits, and low-oil dishes.

Other than what to eat, how to eat is also of great importance. Many people like watching TV while eating. They regard it as a way to relax, but in fact, this is based on a misunderstanding. Watching TV while eating will increase the burden on the body and make people more tired.

When eating, the organs responsible for digestion need blood supply to transport and digest food. Watching TV increases brain activity and thus consumes more blood, and the blood and energy supplied for digestive organs will be reduced, affecting food digestion and absorption. If people’s attention is all on the video, they cannot chew carefully and swallow slowly, and the food will become cold and difficult to digest. In addition, watching while eating will activate the brain and inhibit gastrointestinal peristalsis. This reduces the secretion of digestive fluids, which will affect digestion and absorption. Early satiety, bloating, belching, loss of appetite, malnutrition, emaciation and other symptoms of dyspepsia will occur.

The dyspepsia and insufficient production of blood and qi may lead to heart abnormalities, manifesting as insomnia, lassitude and so on. Therefore, during lunch, people should not only ensure nutritional balance, they should also pay attention to adjusting eating habits, such as less TV, less talking and concentrating on eating.