Question: I read your column on feeding the gut microbiome and, as a lover of honey, was encouraged to see it listed as a prebiotic. However, many argue that honey is just another form of sugar, to be avoided. Is the research on honey as a prebiotic to be trusted?
Answer: Human use of honey for health reasons dates back some 8000 years, with Stone Age paintings depicting its use, along with records of Egyptians, Assyrians, Greek, Romans and Chinese using honey for wounds and gut problems.
Closer to home, mānuka honey is prized for its medicinal properties. The honey comes from bees who forage on our native mānuka trees, which are considered a taonga by Māori, who have a long history of using the mānuka tree to treat a wide range of health issues, including stomach problems.
But where does research sit on the use of honey for gut health? Many honey types have well-established scientific evidence of antibacterial, anti-inflammatory, wound-healing and antioxidant activities. Some varieties are known to be especially potent in this regard, most notably mānuka.
Honey also contains non-digestible oligosaccharides (a form of carbohydrate), and emerging research from laboratory, animal and some pilot human studies suggests they have a prebiotic capability.
Prebiotic is the name given to non-digestible compounds found in food that promote the growth or activity of helpful microbes in our gut. Probiotics are the live microorganisms that are fed by the prebiotics. In layman’s terms, probiotics are the beneficial little critters that live in your gut, and prebiotics are essentially the fertiliser you feed them with.
Dietary fibre is a prime example of a beneficial prebiotic. Other food sources of prebiotics, apart from honey, are garlic, asparagus, onion, Jerusalem artichoke, wheat, banana, barley, tomato, rye, soybean, human and cow’s milk, peas and beans.
So, you can positively boost the amount and variety of good bacteria in your gut by consuming probiotic-containing foods such as yoghurt or other fermented foods. And you can help them to thrive and grow by eating a diet rich in prebiotic-containing foods.
When good bacteria ferment the non-digestible fibres in our diet, they produce short-chain fatty acids, such as butyrate, acetate and propionate. These may decrease cancer risks, improve laxation, and generally help promote a healthier gut barrier with their anti-inflammatory, anti-tumorigenic and antimicrobial effects.
However, while there is a growing recognition of the potential for components in honey to have a prebiotic effect, the research is limited. Although many studies have examined honey’s impact on bacteria in lab tests or animal trials, few clinical trials have explored its effect on gut microbiota in humans. The effects of honey’s prebiotic components on the gut microbiome of a healthy person, or someone with a gut issue, are still relatively unknown, according to a 2022 review by Sydney and London researchers, published in Frontiers in Nutrition.
Then there is the sugar issue. The World Health Organisation recommends limiting free sugar intake to less than 10% of total energy intake (no more than 12 teaspoons a day) to reduce the risk of dental caries and non-communicable conditions such as cancer, diabetes and cardiovascular disease. Reducing sugar intake to less than 5% of total energy intake, or about six teaspoons of free sugar daily, creates further health benefits.
Free sugars are defined as all monosaccharides (eg, glucose and fructose) and disaccharides such as refined white table sugar (sucrose) added to foods by the manufacturer, cook, or consumer – and that includes sugars naturally present in honey, syrups and fruit juices.
So, yes, honey might have a prebiotic effect, but we still do not know to what degree. Conversely, we do know that excessive intake of free sugars, such as those in honey, increases our risk of certain health conditions. Thus, your best bet is to enjoy the occasional serving of honey as part of a varied diet.
