Recent studies suggest that spicy foods offer multiple health benefits beyond their flavorful taste. On one hand, spicy foods can help control weight by slowing down eating speed and reducing food intake, while also promoting cardiovascular health. On the other hand, ethyl acetate extract from Sichuan pepper has been shown to enhance the astrocyte-neuron serine shuttle in the brain, improving cognitive function in aging mice and potentially offering anti-aging effects. Therefore, moderate consumption of spicy foods and spices like Sichuan pepper may not only add flavor but also contribute positively to weight management and brain health.
Our love for “spicy and numbing” foods is not just a sensory experience—it holds a deeper connection to our taste buds, physiology, and even psychology. What's more interesting is that the sensation of numbness and spiciness is more than just a satisfying culinary experience; it may also bring about several health benefits!
Spicy Foods Can Slow Down Eating, Reduce Caloric Intake, and Benefit Blood Pressure
A recent study published in Food Quality and Preference by researchers from Penn State University in the U.S. found that increasing the spiciness of a meal (by adding chili powder) can effectively slow down the eating rate and reduce the frequency of bites. This leads to a reduction in overall food and energy intake, without negatively affecting the enjoyment of the meal.
https://doi.org/10.1016/j.foodqual.2025.105566
Through crossover experiments, it was found that increasing the spiciness of a meal (by adding chili powder) can effectively slow down eating speed and reduce the frequency of bites, thereby reducing the overall food intake and energy consumption. This effect was not due to a decrease in the palatability of the food or an increase in water intake, and it did not affect the enjoyment of the meal.
Existing studies suggest that the texture (such as hardness, smoothness) and geometric shape (such as unit size) of food can influence food intake by altering oral processing behaviors, such as eating speed and bite size. However, when the focus shifts to other non-textural, non-geometric properties of food (such as the burning sensation caused by chili), the mechanisms at play during the oral processing and their potential impact on actual intake remain areas of ongoing research.
Capsaicinoids, the special natural chemicals in chili, are the core "behind-the-scenes agents" responsible for the characteristic burning sensation experienced after consuming chili-containing foods. Although recent research hints that enhancing the burning sensation of food by adding chili may alter oral processing behaviors, the downstream effects of this intensified burning sensation on overall food intake have yet to be directly and systematically verified through experiments.
The study involved three randomized crossover experiments with 57 participants, aged 20-60, who regularly ate three meals a day and were willing to consume spicy food. The participants ate spicy and mild versions of beef chili or chicken curry, with the spiciness adjusted by varying the ratio of hot to sweet chili powder. The team used video recordings to analyze eating behaviors, such as eating speed and bite frequency, and measured the food intake using a weighing method. They also gathered participants’ sensory evaluations and appetite feelings.
The results showed that when the meal was spicy, participants ate significantly less. Specifically, compared to the mild version of beef chili, the spicy beef chili led to an 11% reduction in food intake, while spicy chicken curry led to an 18% reduction. Additionally, the speed of eating and the frequency of biting both decreased significantly with spicy meals, with the slower eating rate being the key factor behind the reduced food intake.
Interestingly, the study found no significant difference in food preference, water intake, or appetite levels before and after meals, indicating that people weren’t eating less because they disliked the spicy flavor. Rather, it was the spiciness itself that led to a slower pace of eating.
Figure: Comparison of eating speed and biting frequency
This suggests that “eating spicy foods for weight loss” may actually have some scientific merit!
Spicy Food and Hypertension: A Study in China
Another study published in Nutrition & Metabolism provides additional evidence supporting the health benefits of spicy foods. This research, based on a large-scale survey in Zhejiang Province, China, found that people who consumed spicy foods more frequently had a lower risk of hypertension. Specifically, compared to people who never ate spicy food, those who ate spicy food less than once a week, once or twice a week, and three or more times a week had significantly lower odds of developing high blood pressure. The study showed a clear correlation: the more often people ate spicy foods, the lower their risk of hypertension.
The Health Benefits of Numbing Spices: Sichuan Peppercorn
In addition to the heat of chili, the numbing sensation brought by spices like Sichuan peppercorn also offers some surprising health benefits. Recent research published in the Journal of Agricultural and Food Chemistry revealed that an ethyl acetate extract of Sichuan pepper (Zanthoxylum bungeanum) could improve cognitive function by facilitating the astrocyte-neuron serine shuttle in aging mice.
DOI: 10.1021/acs.jafc.4c12077
As we age, the functioning of the prefrontal cortex and hippocampus often declines, largely due to a reduction in the efficiency of the astrocyte-neuron serine shuttle. This shuttle is crucial for maintaining brain health, and its decline has been linked to cognitive impairments. The study demonstrated that the ethyl acetate extract of Sichuan pepper could significantly enhance the glycolytic flux in astrocytes, which is important for the synthesis of L-serine, a critical amino acid for the brain.
In experiments with aging mice, the Sichuan pepper extract improved the serine shuttle and helped restore the function of synapses in the brain, which is crucial for memory and cognitive abilities. The extract also showed similar effects to known cognitive enhancers like donepezil (a drug used to treat Alzheimer's disease) and L-serine supplementation.
Summary
In conclusion, spicy foods can slow down eating speed, helping with weight management and calorie control, without negatively affecting food enjoyment. They also offer potential cardiovascular benefits, such as promoting healthy blood pressure. On the other hand, Sichuan pepper, often associated with the numbing sensation in Chinese cuisine, shows promise as a brain health booster by enhancing the astrocyte-neuron serine shuttle, offering potential protection against age-related cognitive decline.
However, it's important to consume spicy foods in moderation. Excessive consumption may irritate the stomach lining and cause digestive issues like mouth ulcers or diarrhea, especially for those with sensitive stomachs.
References:
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Paige M. Cunningham, Isaiah M. Smith, John E. Hayes. "Increasing the spiciness of a lunch meal influences oral processing behaviors and decreases food and energy intake." Food Quality and Preference, 131 (2025) 105566.
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Wang H, Chen L, Shen D, et al. "Association between frequency of spicy food consumption and hypertension: a cross-sectional study in Zhejiang Province, China." Nutr Metab (Lond), 2021;18(1):70.
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Zhao M, Zeng L, Zhou Y, Yang C, Sheng R, et al. "Ethyl Acetate Fraction of Zanthoxylum bungeanum Ameliorates Cognitive Deficit by Facilitating the PHGDH-Dependent Astrocyte-Neuron Serine Shuttle in Aging Mice." J Agric Food Chem, 2025 Jul 2;73(26):16301-16316.