Interesting facts became known in Jurie van der Walt’s research on food in ancient cultures. He has published two books, namely The history of food and why we eat it (2020), and We need to revive the ancient indigenous food crops of Africa.

“I do most of my research on the internet but try to contact the authors of books and articles to get information from them,” says Jurie. “In many instances they refer me to more resources. In this way, I have contacted the Potato Centre in Peru, the University of Greenwich in London, World Vision in Australia, and the Virginia University in the USA.”

His interest in ancient foods started in his mother’s kitchen. “My mother is an excellent cook and I learned by watching her. While working as a journalist in Africa, I became interested in how people in rural areas cooked and how the poor among them survived.

While farming rice in Mozambique, I learned most about how and what the people cultivate and eat. I have always liked to experiment; that nearly caused my death when I ate poisonous mushrooms!”

The African continent has for a long time been affected by political turmoil, drought, and famine. Rapid changes in climate are putting even more pressure on food security on a continent where many are suffering from malnutrition and obesity.


But according to Jurie there is a solution at hand. “There are numerous neglected and forgotten plant species (NUS) in Africa that are simply not enjoying enough attention, considering their excellent nutritional value and how they can aid households to diversify their diets in an affordable and sustainable manner.”

Green Revolution

It is a major challenge worldwide to provide enough, nutritious, and affordable food that is produced in a sustainable way. Although the number of people who are hungry has been halved since the Green Revolution, hunger and food insecurity remain and people are still poorly nourished.

The amaranth (Amaranthus blitum). Several amaranth marog species are collected from the wild and only a few are cultivated.

The Green Revolution refers to the change in agricultural practices that American scientist Norman Borlaug started in Mexico in the 1940s. As a result of Borlaug’s combination of wheat varieties and mechanised agricultural technologies, Mexico, who had to import wheat before, became an exporter by 1960, as the concept produced crops with a higher yield per hectare.

The highest-yielding varieties of rice, wheat and maize were selected and bred to be insensitive to the length of a day and the number of hours of available sunlight.

The development of irrigation systems, the storage of water in dams and the distribution of water to drier areas, reduced the dependence on regular rainfall. These crops, however, were dependent on fertiliser to maintain the higher yield, and some of them were more prone to pests, so the use of pesticides became the norm.

Although the Green Revolution has changed farming and reduced the likelihood of famine, it is criticised for having increased global overpopulation. It has also led to malnutrition and obesity, especially in developing countries. Also, farming methods are not climate friendly and contribute to environmental issues, including loss of biodiversity, greenhouse gas emissions, the degradation of soil, water pollution, and air quality.

The fruit of the baobab tree contains more vitamin C than oranges

Poor nourishment

While the proportion of people who are hungry on our planet has halved since the early days of the Green Revolution, trends in hunger and food insecurity consistently reveal a situation in which populations remain poorly nourished.

This situation is set to become even more dire. Undernutrition of children in some African countries leads to stunted growth and half the deaths of children under the age of five. Hungry children cannot learn and two in five children leave school without knowing how to read, write or count. Very few, especially girls, attend secondary school.

This does not bode well for the youth of Africa, where the average age of the population is 19, and it is expected to get younger. Africa is also experiencing the highest population growth, and it is estimated that two out of every five children born in the world, will be in Africa by 2050.

In addition, Africa’s urban population is the fastest growing in the world, and by 2050, about 1,34 billion people will live in urban areas in Africa. This is a major challenge to African countries to provide enough nutritious food for people in cities.

The spider plant’s (Cleome gynandra) leaves and shoots are usually boiled or used to prepare soups.

The main cause of malnutrition is a diet that is poor in nutrition. Although large quantities of food are produced, these foods do not contain enough nutrients. This situation can be rectified by reintroducing plants that have been cultivated by families on small farms for centuries.

“These plants offer more nutrients than monoculture crops and vegetables introduced from western countries during colonialisation, as well as bioactive non-nutrients that contribute to dietary health,” Jurie says. “This food diversity represents a natural wealth for many countries, yet most, if not all, fail to use them adequately for this purpose.”


Out of more than an estimated 300 000 plant species worldwide, only 7 000 have at some stage been used for food. Up to 200 have been cultivated widely, while only about 150 have been commercialised as food crops.

Today, only twelve plant crops and five animal species provide three-quarters of the world’s food. Wheat, maize, and rice supply half the daily calories (energy) of all the people on earth.

Despite the awareness of the nutritional value of these plants, there are some difficulties that need to be overcome. The early hunter-gatherers made use of a wide range of wild plants and animals, but through domestication of crops and livestock, the intake of a variety of foodstuffs changed.

Ongoing revolution, or development since the Neolithic period has led to the shrinking of the diversity. Neolithic refers to customs characteristic of the last phase of the Stone Age, an early period of human history when people used tools and weapons made of stone, not metal.

The Neolithic period started about 10 000 years ago and is characterised by the beginning of farming, domestication of animals, and weaving and pottery. Over time, as food production changed, fewer plants were cultivated and the world started to rely on monoculture, which is high-yielding and genetically similar crops. As a result, NUS species started to fade into the background.

Market stalls in Zambia sell vegetables.

This occurred despite proof that ancient foods contain more nutrients than modern vegetables:

Ethiopian kale (Brassica carinata) is a popular leaf crop in Africa and its seeds are used as relief from stomach aches.

  • Amaranth (Amarnathus dubius) has 200 times more vitamin A and ten times more iron than the same portion of cabbage (Brassica oleracea);
  • Amaranth has nearly 3,5 times more beta-carotene than cabbage;
  • Malabar spinach (Basella alba) has 13,5 times more iron than cabbage;
  • Ethiopian kale (Brassica carinata) has 5,7 times as much beta-carotene as cabbage;
  • Jute mallow (Chorchorus olitorius) has 6,3 times more beta-carotene than cabbage;
  • Spider plant (Cleome gynandra) has 2,5 times more beta-carotene than cabbage;
  • Baobab (Adansonia digitata) has six times more vitamin C than oranges.

The genetic diversity and nutritional value of neglected and underutilised species have not been fully analysed, probably because it is costly, and it is not regarded as a priority. “Nevertheless, their inclusion in diets could reduce nutrient deficiencies and offer more local, sustainable and culturally acceptable solutions to problems of malnutrition in many parts of the world, including Africa,” says Jurie.

Dry, but rich in biodiversity

Malabar spinach (Basella alba) is different from other spinach types because it is a perennial climbing herb

Despite Africa being an arid continent, it is very rich in biodiversity. This biodiversity is waiting to be rediscovered. These plants can be successfully cultivated on small-scale farms in Africa, where it is mostly the women who
farm. A shift towards these plants could improve not only food security, but also help mothers to provide healthy, nutritious food for their children.

In the next chapter, we shall discuss the plants people used to eat and their nutritional, medicinal and cultural value, the reasons why they ceased to be cultivated, and how the use of these plants can be brought back to small-scale farms and kitchens in Southern Africa. In follow-up chapters, ten of these plants, their value and how to cultivate, prepare and store them, will be discussed.

For more information contact Jurie van der Walt at


Briney, A. (2020, January 23). History and overview of the Green Revolution: how agricultural practices changed in the 20th century.

Definition of Stone Age. Collins Dictionary

Hajjar, B. (2020 January 13). The children’s continent: keeping up with Africa’s growth. World Economic Forum

McVeigh, K. (2018, November 1). Act now or a billion young Africans will be undone by 2050 – Mandela widow The Guardian