Emerging scientific evidence suggests that caffeine affects people differently, with some South Africans more vulnerable to side effects such as anxiety, heart palpitations and disrupted sleep patterns.
Health experts say an estimated 10% of people who consume caffeine products are classified as “slow metabolizers”, meaning caffeine remains in their systems for longer periods and can trigger stronger reactions even in small amounts.
Researchers have also warned that ageing and hormonal changes may intensify the effects of caffeine sensitivity.
According to South African Rooibos Council spokesperson Adele du Toit, consumers are increasingly turning to caffeine-free beverages and herbal infusions, particularly later in the day.
“People are becoming more sensitive to caffeine. About 10% of people are slow metabolizers, and that influences their sleeping patterns,” Du Toit said.
“And we’re seeing consumer behaviour moving more towards having herbal and other infusions later in the day to help people sleep better.”
Du Toit explained that around 40% of people are considered fast metabolizers, meaning they can process caffeine relatively quickly, while approximately 50% fall into the intermediate category.
“About 50% of people are intermediate, and then 10% are slow metabolizers, which means caffeine can stay in their system much longer and even small amounts can lead to stronger and more prolonged effects,” she said.
Caffeine remains the world’s most widely consumed psychoactive substance, but experts say its impact can vary significantly depending on an individual’s metabolism and overall health profile.