Already lauded for its many health benefits, Rooibos is gaining increasing attention in the fight against obesity and related conditions, such as type 2 diabetes (T2D) and cardiovascular disease (CVD). In a first-of-its-kind study, researchers will be probing the effects of real-world Rooibos consumption in human subjects.

Prof Elmarie Terblanche, research lead at Stellenbosch University

Prof Elmarie Terblanche, a leading researcher from the Department of Exercise, Sport and Lifestyle Medicine at Stellenbosch University, is spearheading a groundbreaking study to explore these benefits in depth.

“Our study aims to investigate the health effects of Rooibos consumption in women who are overweight or obese,” she explains. “We are particularly interested in examining changes in body composition, inflammation, glycaemic control and cardiovascular fitness.”

 
The study is meticulously designed, involving four distinct groups:

  1. Rooibos only
  2. exercise only
  3. Rooibos plus exercise; and a,
  4. control group

Women in the two Rooibos groups will consume six cups of Rooibos daily for eight weeks, while those in the exercise group will participate in supervised high-intensity interval training sessions three times a week with no Rooibos consumption. “Each exercise session lasts about 20 minutes, yet it’s as effective in improving cardiovascular fitness as traditional 60 minute sessions of low to moderate intensity exercise,” notes Prof Terblanche.

The study’s first phase, which began recently, involves women aged 18-40. The second phase, slated for completion by mid-2025, will focus on women over 40 who are pre-diabetic or diabetic.

Why Rooibos?

Rooibos is rich in unique polyphenols, which are known for their antioxidant properties. These compounds have shown promise in preliminary studies involving cell cultures and animal models. Prof Terblanche says there is substantial evidence suggesting that Rooibos can improve cardiovascular and metabolic health, however, most of these studies have used Rooibos extracts in concentrated capsule forms. Our study is the first to examine the effects of Rooibos consumption – in tisane (herbal infusion) form – in humans, specifically women.”

Prof Terblanche and her team will conduct a series of tests to measure markers of inflammation, glycaemic control and cardiovascular fitness. Participants will undergo blood tests, body composition analyses and treadmill fitness assessments. This comprehensive approach aims to provide a clearer picture of how Rooibos influences various health parameters.

“We will also consider participants’ diets, as high carbohydrate intake could potentially undermine the positive effects of Rooibos,” she explains. “No previous studies have accounted for diet in this way, making our research unique.”

Potential impact on T2D and CVD treatment

Obesity is a major risk factor for chronic diseases like T2D and CVD, contributing to insulin resistance, pathological fat distribution and chronic inflammation. Traditional pharmaceutical treatments for these conditions often have  significant side effects and are not always accessible, particularly in low- and middle-income countries.

“Healthy eating and regular exercise are crucial in managing and preventing T2D, CVD and many other diseases of lifestyle,” says Prof Terblanche. “However, many people struggle to maintain these healthy habits. Rooibos could provide a simpler, more accessible intervention.”

She is cautiously optimistic about the potential of Rooibos. “If regular Rooibos consumption can offer the health benefits suggested by animal studies, it might be a viable option for those unable or unwilling to adhere to strict exercise regimens. However, whether Rooibos alone can mitigate the effects of a poor diet remains to be seen.”

Despite the promising preliminary evidence, long-term studies on the effects of Rooibos in humans are scarce. “Current research suggests a dosage of six cups per day, but this is based on short-term studies. We need more comprehensive, long-term research to determine if Rooibos can be a sustainable remedy for managing T2D and CVD.”

Prof Terblanche’s study is a significant step in this direction. By examining the combined effects of Rooibos and exercise, and considering dietary influences, the research aims to provide actionable insights into the potential of Rooibos as a health intervention.

The quest for effective, accessible treatments for obesity-related conditions like T2D and CVD is ongoing. Her study represents a pioneering effort to explore Rooibos’ potential in this context. “I’m confident about Rooibos, but as researchers, we need to test it in real-world conditions. If our findings are positive, it could pave the way for more focused research and ultimately provide a natural, accessible option for improving health outcomes.”

As the study progresses, the scientific community and the public alike will be watching closely, hopeful that this beloved South African tisane might hold the key to better health.