A diet has been highlighted as having a dramatic effect on issues such as Alzheimer’s, arthritis, blood pressure, inflammation and heart problems – even in just two weeks. The new diet breakthrough focused on that eaten on east African country Tanzania.

A study in Nature Medicine found that shifting to a diet typical of the East African country — rich in vegetables, legumes, ancient grains and fermented foods — for just two weeks had strikingly positive effects. In fact the researchers suggested that the benefits rivalled those of the famed Mediterranean diet.

Inflammation has been highlighted as an issue which is absolutely crucial for deadly conditions such as dementia and the Tanzanian diet was found to have a very beneficial impact. Proteins in the blood linked to a cluster of conditions, including heart attacks, strokes and insulin resistance, also fell.

The research involved 77 healthy men from urban and rural areas of northern Tanzania. Those who usually ate a traditional diet adopted western-style food for two weeks, switching to meals that included roast beef and mashed potatoes for dinner and egg and chips for lunch.

Participants who switched to a Western diet exhibited an increase in inflammatory proteins in their blood, alongside activation of biological processes linked to lifestyle diseases. Their immune cells also responded less effectively to pathogens. Meanwhile, those who switched to a traditional African diet or consumed the fermented drink showed a reduction in inflammatory markers. Some of these effects persisted even four weeks later, indicating that short-term dietary changes can have long-lasting effects.

What was the Tanzanian diet?

The diet tested in the study was representative of the traditional cuisine of the Chagga people, who live on the slopes of Mount Kilimanjaro. Their cuisine is largely plant-based, featuring ingredients such as plantains, beans, millet and sorghum, and probiotic-laden fermented foods and polyphenol-rich fruits and vegetables. One staple dish, kiburu — a porridge made from green plantains and kidney beans — was among the recipes offered to the participants.

Dr Quirijn de Mast, one of the study’s authors, suggested that other cuisines on the continent may offer similar benefits. “The Mediterranean diet has been extensively studied, but African heritage diets hold untapped potential for promoting health,” he said. “These diets are diverse, rich in fibre and feature unique food products that may offer specific health advantages.”

Rapid urbanisation and a proliferation of processed foods have led to a decline in traditional dishes across much of Africa. De Mast noted that at the same time, conditions that were once rare in the region — such as inflammatory bowel disease and type 2 diabetes — were on the rise.

Dr De Mast said: “The core principle is unprocessed, fibre-rich foods,” However, he added that ancient African grains such as teff might have specific health benefits that would merit further study. “Africa harbours an extraordinary diversity of traditional diets, many of which are still under-explored in scientific research, and are at risk of disappearing before we fully understand their potential,” he said.

“Previous research has focused on other traditional diets, such as the Japanese or Mediterranean diet’. 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.’

De Mast finds it remarkable how significant the effects of diet are, even after just two weeks. “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. 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, which makes this study highly relevant for Western countries as well.”

Green plantain porridge with kidney beans (kiburu) — a Kilimanjaro staple

Ingredients
500g kidney beans (soaked overnight)
1 bunch of green plantains (about ten pieces)
A pinch of salt and soda ash (for flavour)

Method

• Drain the soaked kidney beans, place them in a large pot and cover with water.
• Bring to a boil and simmer for 30–40 minutes until the beans are half-cooked and soft to the touch.
• While the beans are boiling, peel the green plantains and cut them into small cubes. Add cubes to the pot with the boiling beans.
• Sprinkle in a pinch of salt for taste. Add a pinch of soda ash soaked in a little water.
• Simmer the mixture for another 30 minutes until the beans and plantains are fully cooked and tender.

To serve

• Once cooked, gently mash the mixture into chunky porridge. Adjust the consistency as desired.
• Serve with avocado, cucumber and carrot; you can also add spinach.