A recent experimental study investigated the effects when Tanzanian men transitioned from their traditional African diet to a more Western-style eating pattern.
Many of us have considered modifying our diets for better health, whether reducing carbohydrate intake or exploring vegetarian options.
While scientific research has compared vegan and meat-based diets extensively, what about the health impacts of geographical dietary patterns?
Researchers sought to answer this question by having 77 East African men abandon their traditional Tanzanian eating habits in favor of a specific ‘western diet’ regimen.
The 2025 research paper, “Immune and metabolic effects of African heritage diets versus Western diets in men: a randomized controlled trial,” represented a collaboration between Radboud University and KCMC University scientists examining how a processed food-heavy Western diet would affect participants’ health over a two-week period.
The implemented ‘Western diet’ consisted of items such as beef sausage, fried chicken, pizza, potato chips, white rice, macaroni, and eggs with minimal fruits or vegetables—certainly not considered nutritionally optimal by any standard.
Predictably, this dietary shift produced detrimental health outcomes.
According to the findings, participants gained approximately 5.7 pounds on average, while blood analyses revealed elevated inflammatory proteins and metabolic alterations associated with chronic health conditions including heart disease and type 2 diabetes.
Furthermore, their immune system functionality decreased, with immune cells showing reduced effectiveness against harmful pathogens, thereby increasing vulnerability to infections.
Additionally, even after participants reverted to their customary eating patterns, certain negative effects persisted for up to four weeks.
Conversely, individuals who adopted a traditional Tanzanian diet—rich in vegetables, fruits, legumes, brown rice, whole grains, root vegetables, tubers, fermented foods and moderate meat consumption—demonstrated decreased inflammatory proteins and favorable metabolic changes in their bloodstream.
The researchers note that this represents the first study specifically examining the health implications of an African dietary pattern.
“Previous research has focused on other traditional diets, such as the Japanese or Mediterranean diet,” stated Dr. Quirijn de Mast (as reported by Science Daily). “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.”
Dr. de Mast emphasized that their experiment demonstrated the unhealthy and harmful nature of this ‘western diet’ for overall health, while highlighting the “benefits of these traditional food products for inflammation and metabolic processes in the body.”