Cardiovascular diseases remain among the world’s leading killers, but everyday foods like rooibos tea and broccoli may hold the key to protecting the heart, according to new research from the North-West University (NWU).

This was the core finding of the PhD study of Dr Sinenhlanhla Xoliswa Happiness Mthembu, who explored plant-based compounds that could help counter heart damage caused by metabolic disorders.

Her study addressed the pressing question of why cardiovascular complications continue to rise despite the availability of conventional therapies. The findings point to affordable, plant-based interventions as a potential solution.

While the body naturally produces disease-fighting antioxidants such as coenzyme Q10, which is critical for heart health, metabolic complications such as dyslipidemia can disrupt these molecules.

“Natural compounds such as aspalathin from rooibos and sulforaphane from broccoli can restore antioxidants, improve energy metabolism, and shield heart cells from oxidative damage,” says Dr Mthembu. “This could improve outcomes for patients facing cardiovascular complications.”

Dr Mthembu’s work has already made a mark, with 26 peer-reviewed publications and an h-index of 15, reflecting her growing influence in mitochondrial biology and cardiometabolic health.

From rural village to international recognition

Hailing from Bergville, KwaZulu-Natal, Dr Mthembu completed her BSc, honours, and MSc degrees in biochemistry at the University of Zululand before joining the NWU in 2021 in collaboration with the South African Medical Research Council (SAMRC).

“At the SAMRC is where my life changed. I was introduced to state-of-the-art research equipment and mentored by my supervisor, Prof Sithandiwe Mazibuko-Mbeje, who guided me step by step.”

Global fellowships and awards

Her dedication to research has earned her international recognition. At the Young Scientists Forum in Turkey earlier in 2025, she was the only South African and the only black candidate selected for a fellowship of the International Union of Biochemistry and Molecular Biology/Federation of European Biochemical Societies.

She also received the 2024 IUBMB MilliporeSigma ENABLE-Africa Fellowship in Singapore and the South African Women in Science Award DSI Esther Mahlangu Doctoral Fellowship.

Reflecting on her research, Dr Mthembu says, “Science is about finding solutions that can make life better. If a simple plant compound can prevent heart damage, then that’s a path worth pursuing.”

Dr Sinenhlanhla Xoliswa Happiness Mthembu