, according to researchers from the Institute of Sciences at Benemérita Autonomous University of Puebla, Puebla, Mexico.
Their study, published in the journal Foods, is the first to produce tables showing the phenolic content of Mexican dishes. Physicians and nutritionists can use this information as a reference tool when drawing up diet recommendations for patients who could benefit from a higher intake of phenolic compounds (PC).
“Up until now, there hasn’t been a table that we – nutritionists and physicians – could look at and see exactly which foods were richest in these compounds. In the United States, European countries, Asian countries – they’ve all had food tables; in Mexico, we didn’t,” said lead author Julia Alatorre-Cruz, PhD, a biological scientist and postdoctoral researcher at BUAP. “So, it’s a fairly innovative contribution. As a bonus, the information can be used to analyze the relationship between diet and noncommunicable diseases in the Mexican population.”
In recent years, nutrition science has focused on counteracting nutrient deficiency and some diseases by identifying active-food components. Diet offers the possibility to improve the patient’s health conditions by using these components or functional food.
PCs are a diverse group of plant micronutrients, some of which modulate physiologic and molecular pathways involved in energy metabolism. They can act by different mechanisms; the most important of them are conducted by anti-inflammatory, antioxidant activities, and are antiallergic.
Moreover, recent studies explain how PCs positively affect certain illnesses, such as obesity, diabetes, cardiovascular diseases, thrombocytopenia, and metabolic syndrome. Several common features characterize these pathologies – among them are the redox balance and a notable inflammatory response that strongly alters the biochemical and functional characteristics of the affected tissues.
Traditional Mexican food is characterized by grains, tubers, legumes, vegetables, and spices, most of which are rich in PCs. However, the Mexican diet has changed over the past decades because traditional food has been replaced with ultraprocessed food with high-caloric values. Moreover, some vegetables and fruits are preferably consumed after processing, which affects the quantity, quality, and bioavailability of the PCs. In addition, diseases associated with eating habits have increased by more than 27% in the Mexican population.
The objective of the study was to determine whether participants with a higher PC intake from beverages or Mexican dishes have better health conditions than those with a lower intake.
A total of 973 adults (798 females, 175 males) aged 18-79 years were enrolled in this cross-sectional study. The data were obtained from a validated, self-administered food consumption survey that was posted on social media (Facebook) or sent via WhatsApp or email. In one section, there was a list of fruits, vegetables, cereals, legumes, seeds, spices, beverages, and Mexican dishes. The participants were asked to indicate how often in the past month they had consumed these items. There were also sections for providing identification data (for example, age, sex, marital status), height and weight information, and medical history.
“The study was carried out during the pandemic, so that limited contact with the participants,” said Dr. Alatorre-Cruz. “Not being able to directly interact with them was a challenge. For example, we would have liked to have taken those anthropometric measurements ourselves.”
The researchers performed K-means clustering to determine the participant’s health-condition level, resulting in two groups: those with less diseases (LD, n = 649) and those with more diseases (MD, n = 324).
Using the food biochemistry composition reported in multiple papers, the researchers computed the average total phenolic compounds (TPC) for each item listed in the survey. For Mexican dishes, they added the TPC of each recipe’s ingredient, then recalculated to come up with TPC for an individual portion of each recipe (TPCr). To analyze the results of the LD group and of the MD group, phenolic compounds intake of recipe was calculated for each participant.
To Dr. Alatorre-Cruz, the biggest challenge was determining the content of compounds in traditional dishes. “Extensive, in-depth research was done to gather as much information as possible about all of the foods – especially about local and regional ones, because we have such a wide variety – looking to see where that information would match up with the exact method with which the compounds of interest were extracted.”
As expected, the team found that food with high PC was associated with a better health condition. However, the consumption of beverages and Mexican dishes was lower than their expectations. As noted in the article, the Mexican diet has changed over the last decades because traditional food has been replaced with ultraprocessed food with high-caloric values.
The authors suggest that their data confirm the alarming changes previously reported in the Mexican diet – changes possibly attributable to the increased influence of other countries via social media and economic globalization. However, they also found that beans, corn (mainly tortilla), and nopal intake remained preserved in the Mexican eating habits.
Their statistical analyses revealed that sex, age, and education seem to play a role in the presence or absence of diseases in the Mexican cohort. Men, participants over age 29 years, and those with lower levels of education had more diseases.
Dr. Alatorre-Cruz told this news organization that the Foods article opens new lines of research for the group to pursue. “One future proposal looks to enroll patients with conditions where there’s an increase in oxidative stress – which we know has quite a detrimental effect – and look into possible links with their diet. But now, maybe the focus can be on patients with a single condition and using these traditional-food tables to find links. We also want to know more about the molecular or biochemical mechanisms that are modulating the association that we saw first in animal models.”
Laura Álvarez, MD, a specialist in clinical nutrition, is the founder of the NUTRIENT project, which focuses on nutrition and strength training. In her opinion, the study extols the benefits of Mexican food. “I’ve always thought that people have this idea that Mexican food isn’t good. For example, thinking that it’s very high in fat. But in reality, Mexican food is very rich in nutrients.”
She added that research should be broadened, by enrolling a larger group of participants and evaluating not only a greater number and a greater variety of Mexican dishes, and new variables as well. “I think that body composition could be taken into account. In this study, they took the BMI into account to assess overweight and obesity, but ... the BMI doesn’t tell us much. Overweight can be due to fat or due to muscle. If we could get even more specific and find out what type of fat, that would give us more information about other [possible] diseases that ... need to be taken into account.”
This research was funded by the Institute of Sciences, Benemérita Autonomous University of Puebla. The funders had no role in the design of the study; in the collection, analyses, or interpretation of the data; in the writing of the manuscript; or in the decision to publish the results. Dr. Alatorre-Cruz and Dr. Álvarez have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.