Active ingredient in Manuka honey – Methylglyoxal

ST Forum, 24/8/2015
HSA should review stance on health supplements

According to the Health Sciences Authority (HSA), health supplements can be imported and sold without a licence. These are also not subjected to pre-market approval by the HSA. As it is, some of these health supplements may potentially be harmful to individuals with certain health conditions.

Manuka honey is an example that comes to mind. It is commonly available at local pharmacies and supermarkets. The active ingredient in this supplement is a chemical called methylglyoxal. As a highly reactive dicarbonyl molecule, methylglyoxal readily reacts to certain amino acids as well as to nucleic acids. Apart from Manuka honey, very little methylglyoxal is consumed in the diet. Low amounts of it are produced in the body as a by-product of the normal cellular process of glycolysis, in which glucose is broken down to provide energy.

As it is a dangerous molecule, the human body rapidly detoxifies methylglyoxal using various enzymes. However, for people with certain medical conditions, such as diabetes, eating Manuka honey may increase the level of methylglyoxal beyond the detoxification capacity of the enzymes.
As a result, advanced glycation end-products (AGEs) are formed when methylglyoxal reacts and damages proteins and nucleic acids.

Indeed, a large volume of scientific literature has implicated AGEs as a major mechanism in the development of diabetic complications, particularly diabetic retinopathy, the leading cause of blindness in adults. Besides diabetes, methylglyoxal is thought to play an important role in the process of ageing and in the development of several age-related diseases, including obesity, cancer, disorders of the central nervous system, hypertension and atherosclerosis.

Clearly, it is sensible for individuals with such health conditions to avoid this supplement or at least get advice from their doctors before consuming such products on a prolonged basis.

Daniel Ng Peng Keat (Dr)


ST Forum, 4/9/2015
Regulation of health supplements: HSA, AVA reply

Manuka honey, an example raised by Dr Ng, is regulated by the Agri-Food and Veterinary Authority (AVA) as a food product. Methylglyoxal is a chemical naturally formed in manuka honey during storage over time. A healthy person has natural defence mechanisms to remove methylglyoxal from the body.

There have been various studies with contradictory results on the link of methylglyoxal and several age-related problems such as diabetes. The scientific community is of the view that more research is needed before findings on the health effects of methylglyoxal is conclusive. Like any food product, manuka honey products are required to meet Singapore’s food safety standards and labelling requirements.

In addition, all food products must not carry claims of medicinal and therapeutic properties. Individuals with medical conditions should consult their medical professionals on appropriate dietary choices.

Raymond Chua (Assistant Professor)
Group Director
Health Products Regulation Group
Health Sciences Authority

Astrid Yeo (Dr)
Group Director
Regulatory Administration Group
Agri-Food and Veterinary Authority


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: