Transdisciplinary research aims to dish up food security

The doom of the modern diet

Modern diets and food systems have undergone a rapid, drastic transformation in the past 50 years. Joelaine Chetty, a PhD student in the Division of Human Nutrition and a research dietician in the South African Medical Research Council’s Biostatistics Unit, is connecting the dots. She points out that the deterioration of our nutrition system over the past five decades can be attributed to two factors: the industrialisation of food production and the accelerating impact of climate change.

“The highly processed energy-dense foods we have now are often low in essential nutrients and high in sugar, salt, and unhealthy fats. This shift in dietary patterns contributes to the global rise in obesity and diet-related diseases, while exacerbating malnutrition and micronutrient deficiencies,” she explains.

But that’s not all: The unfolding climate crisis is adding food production and security pressures to the mix. Chetty says: “The increasing frequency and severity of extreme weather events such as droughts, floods, and storms are disrupting and having adverse effects on food production. This, in turn, affects crop yields, livestock production, and distribution networks, leading to food shortages and price volatility.”

Chetty believes, however, that reversing this trend is possible through interventions such as localising and diversifying food systems. She says:

“We have the potential to foster local food production, distribution, and consumption, thereby reducing our reliance on imported goods and strengthening community resilience. By supporting small-scale farmers, local markets, and food sovereignty initiatives, we can significantly enhance food security and economic stability at the grassroots level.

“Promoting agricultural diversification reduces the reliance on a limited number of crops or livestock breeds. Diverse farming systems build resilience against climate variability, pests, and diseases, and can buffer against crop failures and market fluctuations.”

Chetty believes investment in research, innovation, and technology transfer is also crucial to protecting our nutrition system from further deterioration. This involves paying more attention to resilient crop varieties, adapting and improving agricultural practices, and supporting small-scale farmers.

Moreover, Chetty argues, there is a need for what she calls ‘nutrition-specific interventions’ — efforts that not only ensure access to food but also promote diverse, nutritious diets. These interventions include micronutrient supplementation, improving nutrition education, promoting breastfeeding, and strengthening dietary guidelines that encourage the consumption of fruits and vegetables, specifically indigenous vegetables.

Chetty underscores that addressing food security is a collective responsibility that requires coordinated efforts across sectors and stakeholders. She advocates for public-private partnerships and better civil society engagement, as these are essential for mobilising resources, sharing knowledge, and implementing effective solutions at scale.

Giving back indigenous foods their seat at the table

Prof Xikombiso Mbhenyane, head of the Division of Human Nutrition, is a dietician with a particular interest in indigenous food systems. She is also the faculty’s DSI-NRF Research Chair in Food Environments, Nutrition, and Health.

Indigenous food systems, she says, have been excluded from mainstream ones and left to linger on the margins in terms of production, access to markets, and investment. Integrating indigenous foods into the broader markets, however, can strengthen local food systems, she believes.

That said, the challenges in the promotion, production, accessibility, and consumption of indigenous foods are plenty. For instance, Mbhenyane says, the availability and accessibility of indigenous foods still vary widely from province to province, and between the formal and informal markets. Without more consistent, reliable supply chains, consumers are less inclined to normalise indigenous foods into their everyday diets. Additionally, Mbhenyane says, our current food systems — which are failing — will remain unchanged without targeted support for small-scale farmers who grow indigenous crops, or for those who harvest from the wild.

“For indigenous foods to be promoted for cultivation and consumption, we need protection and accessibility in the market,” she says. Land management must balance the importance of land for growth (through commercial or housing developments) with land for food security (through agriculture), Mbhenyane adds.

She also makes the case for subsistence farming and the promotion of urban food gardening. Growing your own food not only supplements your household food supply, she says, it also saves money, restores people’s connection to how food comes to a table, and recovers the forgotten benefits of indigenous foods.

An urban farmer herself, Mbhenyane names two of her favourite indigenous foods of which the nutritional value is often overlooked, and which she believes should be part of our diets: Amaranthus cabbage (Amaranthus thunberghi) and cowpeas (Vigna unguiculata). The first is a semi-wild species of amaranth that grows in southern Africa. Mbhenyane says the plant is rich in micronutrients and can be used in the same way as garlic to flavour dishes. Cowpeas, also called ‘black-eyed peas’, is a versatile, resilient crop harvested for its seeds, pods, and leaves. Apart from being eaten by humans, it is also used in animal feed.

“We also often hear from the older people that cowpeas are eaten as part of a diet that helps to control diabetes, so this is an area of new studies,” Mbhenyane says. More research into indigenous food systems can unlock traditional knowledge, she says, and ensures its preservation in repositories.