Research finds anti-inflammatory and immunity benefits in traditional African diet

Scientists reveal that switching from an African heritage diet to a Western-style diet for two weeks causes inflammation, reduces the immune response to pathogens, and activates processes associated with lifestyle diseases. Meanwhile, consuming an African diet rich in vegetables and fiber or a traditional fermented banana beverage had a predominantly anti-inflammatory effect.

The team from Radboud University Medical Center in the Netherlands and KCMC University in Tanzania conducted a randomized controlled trial with 77 healthy men from Tanzania. The group consisted of urban residents, who typically consume a Western-style diet higher in processed foods, and rural dwellers, who consume a more traditional African diet.

“The African diet includes plenty of vegetables, fruits, beans, whole grains, and fermented foods. Our study highlights the benefits of these traditional food products for inflammation and metabolic processes in the body,” says co-author Quirijn de Mast, an internist at Radboud University Medical Center. 

“At the same time, we show how harmful an unhealthy Western diet can be. It typically consists of processed and high-calorie foods, such as French fries and white bread, with excessive salt, refined sugars, and saturated fats. Inflammation is at the root of many chronic conditions, making this study highly relevant for Western countries.”

Metabolic and immunity effects

For two weeks, participants who typically ate an African diet switched to a Western-style diet higher in processed foods, while a second group switched from their everyday Western diet to a traditional African diet. 

A third group on a Western-style diet consumed a daily fermented banana drink (Mbege) for one week. Ten people maintained their usual traditional African or Western-style diet in a control group. 

After these interventions, all participants went back to their usual diets. 

The team analyzed participants’ immune system function, blood inflammation markers, and metabolic processes at baseline, after the intervention, and after another four weeks. 

Ugali is a traditional dish in Tanzania included in the study, a stiff porridge made from maize and cassava.Participants who switched to a Western diet exhibited increased inflammatory proteins in their blood. The switch also affected metabolic pathways linked to noncommunicable diseases, and their immune cells responded less effectively to pathogens. 

However, the groups switching to a traditional African diet or consuming the fermented beverage showed reduced inflammatory markers. 

“Some of the observed changes in the immune and metabolic profiles persisted at the follow-up, suggesting a sustained impact from the short-term intervention,” conclude the researchers. 

Preserving traditional diets

In their study in Nature Medicine, the researchers underscore that noncommunicable diseases, such as cardiovascular diseases, diabetes, and chronic inflammatory conditions, are surging across Africa. 

Meanwhile, increasing urbanization, economic development, access to processed foods, globalization, and changing social norms drive a growing switch to Western-style dietary patterns in Africa. 

De Mast highlights how significant the effects of diets are, even after two weeks. She says this is the first study to comprehensively map the health effects of a traditional diet compared to Western diets. 

Mbege is an alcoholic drink made from fermenting mashed and cooked bananas.“Previous research has focused on other traditional diets, such as the Japanese or Mediterranean diet,” she notes. 

“However, there is just as much to learn from traditional African diets, especially now, as lifestyles in many African regions are rapidly changing and lifestyle diseases are increasing. Africa’s rich diversity in traditional diets offers unique opportunities to gain valuable insights into how food influences health.”

As their findings show these dietary transitions’ metabolic and immune effects, the study authors underscore the importance of preserving indigenous dietary practices to mitigate noncommunicable disease risk factors in sub-Saharan Africa. 

Meanwhile, the US University of California Davis and Novo Nordisk Foundation’s BioInnovation Institute launched a project this week to develop nutrient-rich interventions based on cultural diets in Africa to help prevent malnutrition and stunting among children. 

At the same time, researchers say that access to regional markets in Africa is more important to achieving healthy, balanced diets than ensuring farmers grow a wide variety of crops on their farms.