How Food Temperature Affects Anxiety and Sleep

Feeling anxious? A warm cup of tea or a bowl of hot soup might help, according to the findings of a new study.

In September, new research led by scientists at San Diego State University was published in the British Journal of Nutrition, examining how foods and drinks served at different temperatures affect both our digestive and mental health. 

As the researchers explained, to understand how the temperature of our food can make us feel, they analyzed data from 212 Asian and 203 White adults (aged 18–65 years) through the university’s Healthy Aging Survey, all of whom lived in the United States. As part of the study, participants self-reported how often they consumed hot or cold drinks and hot or cold meals, as well as how often they experienced symptoms of depression, anxiety, insomnia, and gastrointestinal issues, which the authors noted could include “gas and abdominal fullness.”

The researchers found that among Asian study participants, “higher cold consumption in summer was associated with increased anxiety” as well as abdominal fullness. They also found that Asian participants who consumed the most cold drinks during summer experienced the highest rates of insomnia.

However, the researchers also found that among White participants, those who consumed the most hot drinks in winter experienced fewer insomnia and gas symptoms. They also discovered that Whites who drank the most hot beverages in winter had lower depression levels. When they examined the data further by subgroups, the researchers found that Chinese participants who reported consuming the least amount of cold foods and drinks experienced fewer “adverse outcomes,” while Asian Indian participants also showed stronger associations between cold consumption and adverse health effects.

“Something as simple as the temperature of what we eat and drink can have real impacts on health,” Tianying Wu, an associate professor of epidemiology and the study’s lead author, shared in a statement. “Because cold and hot consumption is such a routine part of daily life in the U.S., at home and in restaurants, the findings have broad relevance to everyday health choices.”

Interestingly, the study also found that the effects were most pronounced in those who frequently reported having “cold hands,” which they noted could be related to poor circulation. The team added in a statement that these findings are consistent with long-standing beliefs in traditional Chinese and Ayurvedic medicine: that consuming too many cold foods or drinks could lead to negative outcomes.

“It is a common understanding in East Asian medicine that we should avoid eating cold foods, [as] cold foods require more digestive energy to process,” Jason Chong, a traditional East Asian Medicine Physician and trainer at Dantian Health, shared with Food & Wine. “It’s like cooking soup on the stove, but starting with a frozen chicken and a frozen block of ice. It takes a lot more energy to produce something.” 

Chong further explained that when the digestive energy is weak, “which in East Asian medicine is related to our spleen organ,” people have more trouble digesting, making it hard to absorb the nutrients the body needs. However, Chong added that “cold” can go beyond the literal meaning as well.

“My perspective on this is that when we talk about cold foods, we are talking about foods that are lacking in Yang energy, which represent vitality and warming,” Chong said. “When we talk about foods that are lacking in Yang, vitality, we’re talking about heavily processed foods. Cold foods can thus also be interpreted as these types of foods which are generally lacking in nutrition.” 

So, you might be doing yourself a double favor by eating a warm, homemade soup, which sounds pretty tasty for dinner anyway.