South Africa’s indigenous vegetables — the extraordinary nutritional wealth in our backyards

This year’s World Food Day on 16 October, celebrated under the global theme “Hand in Hand for Better Foods and a Better Future”, provides an important moment to reflect on what “better foods” truly means.

In an era dominated by discussions of superfoods and nutritional supplements, we often overlook the extraordinary nutritional wealth growing in our own backyards. Nowhere is this more evident than in South Africa’s indigenous vegetables – a treasure trove of nutrition that the science behind what’s in our food (food composition) is only now beginning to fully appreciate.

Food composition data forms the backbone of nutrition science, public health policy and dietary guidelines. These databases tell us what nutrients are in our food, enabling everything from nutrition labelling to dietary recommendations.

Yet for decades, databases have been dominated by information about commercially cultivated crops and imported foods, while indigenous and traditional vegetables remained largely undocumented.

The South African Food Composition Database housed at the South African Medical Research Council comprises 73% South African-sourced data, with minimal indigenous foods represented. This gap represents more than just missing data; it reflects a broader disconnect between modern nutrition science and traditional food systems.

Indigenous vegetables such as pigweed (Amaranthus), spider plant (Cleome gynandra), cowpea (Vigna unguiculata), jute mallow (Corchorus olitorius) and black jack (Bidens pilosa) are valued for their rich micronutrient profiles, adaptability to harsh climates and cultural importance.

These plants have sustained communities for generations, yet their nutritional content has not been fully captured in official food composition databases, rendering them invisible in nutrition planning and policy.

Recent studies have shown that indigenous vegetables are naturally dense in iron, zinc, calcium, vitamin A and dietary fibre – nutrients critical to addressing persistent micronutrient deficiencies in low-income communities.

Amaranth leaves contain exceptional levels of protein, iron, calcium and vitamin A – nutrients often deficient in South African diets. African nightshade (Solanum spp.) provides abundant folate, antioxidants and natural compounds (phytochemicals) with demonstrated health benefits. Cleome gynandra offers omega-3 fatty acids rarely found in leafy vegetables.

These are not marginal crops; they are nutritional powerhouses that have been hiding in plain sight.

The significance of this research extends beyond individual nutrients. Food composition analysis reveals that indigenous vegetables often contain beneficial compounds absent or minimal in conventional crops.

Many are rich in bioactive phytochemicals with antioxidant and anti-inflammatory properties. Rich in fibre and micronutrients, they support gut health and tackle multiple nutritional deficiencies – a critical advantage in regions where malnutrition persists alongside rising rates of noncommunicable diseases.

Research on the composition of food also reveals how processing and preparation can change its nutritional value. Traditional cooking methods, passed down through generations, often help to keep more nutrients in the food and make it easier for the body to absorb.

Understanding these relationships through rigorous food composition analysis validates traditional knowledge while identifying opportunities to get the most nutritional benefits.

This represents the “hand in hand” approach that World Food Day 2025 celebrates – combining scientific rigour with cultural wisdom through partnerships between nutritional scientists, agricultural researchers and local communities.

Generating comprehensive food composition data for indigenous vegetables requires sustained investment and collaboration. Samples must be collected across seasons and growing conditions; analytical methods must be standardised and accredited laboratories identified for chemical analysis of selected components.

This work demands coordination across research institutions, government agencies and farming communities.

The climate resilience of indigenous vegetables adds another dimension to their value. As climate change threatens conventional agriculture, these plants offer proven adaptation to variable rainfall, heat stress and poor soils.

Better food for a better future must be sustainable food, and indigenous vegetables meet this criterion remarkably well. Food composition data documenting their nutritional density makes a compelling case for their role in climate-resilient food systems.

When indigenous vegetables appear in food composition databases, they can be incorporated into dietary guidelines, school feeding programmes, and nutrition interventions. Healthcare providers can recommend them with confidence.

Agricultural extension services can promote their cultivation with nutritional evidence. Food-based dietary guidelines can reflect local food biodiversity rather than importing recommendations developed elsewhere.

South Africa's indigenous vegetable research offers lessons for global food systems. Across Africa and beyond, countless traditional crops haven’t been properly studied for their nutritional value.

Building comprehensive food composition databases for these foods is essential for culturally appropriate nutrition strategies. It represents a form of food sovereignty – the right of communities to have their traditional foods recognised, valued and integrated into formal food systems.

Commercial opportunities also emerge from rigorous food composition data. When nutritional value is documented, indigenous vegetables become attractive to urban consumers, restaurants, and food processors.

Education plays a crucial role in this transformation. Young people disconnected from traditional food systems need exposure to both the nutritional science and cultural significance of indigenous vegetables. Food composition data provides the scientific foundation, but cultural transmission ensures these foods remain part of living food systems.

As we work hand in hand towards better food and a better future, food composition science offers a powerful tool for recognising and restoring the value of indigenous vegetables. South Africa’s research demonstrates how rigorous nutritional analysis can validate traditional foods, support climate adaptation and inform policy.

The path forward requires continued investment in research on the composition of food, integration of findings into policy and practice, and partnerships that honour both scientific and traditional knowledge.

The better food we seek for the future may well be the food that has sustained communities for generations – we simply needed the tools of food composition science to recognise its true value.

As South Africa celebrates World Food Day, the growing evidence demonstrates that indigenous vegetables are more than dietary supplements; they are agents of climate resilience, health promotion and cultural continuity. DM

Joelaine Chetty is a PhD candidate in the Division of Human Nutrition at Stellenbosch University. She is also a research dietician/food composition database compiler at the South African Medical Research Council and the Biostatistics Research Unit at SAFOODS.