Seaweed is abundant in South Africa’s coastlines, and you will often see the thick brown algae washed ashore and carpeting beaches, causing nuisance to swimmers or resorts that see it as an eyesore.
But researchers at University of KwaZulu-Natal (UKZN) say that while these marine plants, known for their medicinal, cuisine and agricultural benefits, often go to waste when removed from shorelines, the latest findings show seaweeds can also be used as a natural remedy to treat obesity and diabetes.
As part of her master’s thesis, UKZN biochemistry graduate S’thandiwe Magwaza extracted and isolated anti-obesity compounds in 23 seaweeds endemic to the country’s southern and western coastlines. Her research shows that medicinal extracts from this sea algae are potentially as potent as standard anti-diabetic drugs, but at a much lower cost and with fewer side-effects.
Seaweed grows along rocky shorelines across the world, but it’s most commonly eaten in Asian countries that use it in many dishes, including sushi rolls, soups, stews, salads, supplements and smoothies.
Magwaza recently received her master’s degree in biochemistry cum laude for her research that evaluated the anti-obesity, anti-diabetic and antioxidant potentials of 23 seaweeds using in vitro and ex vivo experimental models. Testing the efficacy seaweed extracts on rats showed that seaweed has potential to treat diabetes.
Seaweeds have always been consumed in the Korean regions, and its consumption is starting to pick up in other regions worldwide. They are very nutritious, and they are believed to possess many health benefits.
— S’thandiwe Magwaza, UKZN biochemistry graduate
“We tested the ability of the extracts to prevent increased blood sugar levels by measuring the seaweed’s effects on tissue glucose uptake and on intestinal sugar absorption. Thereafter, we selected six seaweeds, which I am working on for my PhD project, and we will be testing the effects of the seaweed’s extracts on obese and diabetic rats,” Magwaza told TimesLIVE Premium.
“There is great demand for natural anti-obesity and antitype 2 diabetes remedies because they cost less and have fewer to no side-effects. A number of seaweeds go to waste, although many medicinal plant extracts and their isolated compounds have been scientifically proven to possess anti-obesity and antitype 2 diabetes properties.”
Given the rise in type 2 diabetes across the world and in South Africa, which is associated with a range of serious health complications, such as heart disease, stroke, kidney disease and certain types of cancer, Magwaza said understanding risk factors and disease management is crucial to improve public health and reduce the burden of chronic diseases.
Research shows that the prevalence of diabetes across the world is expected to rise to about 10.4% (822-million people) by 2040. Diabetes is already one of the top 10 causes of death in developing countries, and its prevalence in SA has rapidly increased from 4.5% in 2010 to 12.7% in 2019.
Magwaza said while seaweeds have been used to treat various ailments in East Asian countries for centuries, the health benefits of seaweeds from South African coastlines are relatively unknown.
Seaweeds are rich in bioactive compounds including polysaccharides, polyphenols and peptides, which have demonstrated potential health benefits. Magwaza said investigating these natural sources for their anti-obesity and anti-diabetic properties can lead to the development of safer and more sustainable therapeutic options.
“Seaweeds have always been consumed in the Korean regions, and its consumption is starting to pick up in other regions worldwide. They are very nutritious, and they are believed to possess many health benefits.”
Magwaza, who is continuing with her research as part of her PhD studies under biochemistry Prof Shahidul Islam’s supervision, said her research focus is finding optimal dosages and efficacy for seaweed extracts.
“In future, we plan to isolate and purify these compounds and analyse them possibly for drug development or any nutraceutical specific for obesity and diabetes. The results were compared with known drugs for diabetes and obesity, such as orlistat and metformin and some of the seaweed depicted excellent or better results than these drugs, but this we will confirm after completion of animal studies and isolation of compounds.”
“The future plan is to produce products derived from the seaweeds since they are natural and may be less costly compared to the currently available synthetic drugs. After completion of the study and everything has been confirmed, including human trial studies, products will be produced,” she said.
Would you like to comment on this article?
Sign up (it's quick and free) or sign in now.
Please read our Comment Policy before commenting.