As health-conscious consumers grow increasingly aware of the substances they ingest, one sugar that's been making headlines lately is trehalose. Trehalose, a naturally occurring disaccharide composed of two glucose molecules, has been recognised for its unique health benefits, including its role in neuroprotection, autophagy promotion, and cell preservation. But while its application in medicine and skin care is gaining ground, many are left wondering: what foods actually contain this sugar, and should we be seeking it out?

Trehalose may not be as well-known as other sugars like sucrose or fructose, but it has been quietly working its way into various food products. From fungi to seafood, trehalose appears in diverse places in nature, with more and more of its sources making their way into the food industry. As researchers uncover its potential health benefits, there's growing interest in incorporating trehalose-rich foods into our diets. Let's explore where trehalose is found in nature, which foods contain it, and how it's being utilised in modern food production.

Trehalose in nature: A brief overview

Before delving into the specific foods that contain trehalose, it's important to understand its biological function in nature. Trehalose is often referred to as a "stress sugar" because it helps organisms survive extreme conditions. It acts as a stabiliser for proteins and cell membranes, allowing organisms to retain their structure during periods of dehydration, heat, or cold. Many plants, fungi, bacteria, and invertebrates rely on trehalose to withstand environmental stressors, such as drought or freezing temperatures.

One of trehalose's most famous natural roles is in the so-called "resurrection plants", which can survive near-complete desiccation for long periods, reviving once water becomes available again. Similarly, certain insects and microorganisms use trehalose to protect themselves during extended periods of dormancy or extreme temperatures.

In the context of human food consumption, this sugar is naturally present in a variety of organisms, most notably in mushrooms, algae, yeast, and crustaceans.

Mushrooms: A rich source of trehalose

Mushrooms are perhaps the most well-known natural source of trehalose. Many species of mushrooms, both wild and cultivated, contain high levels of this sugar. Trehalose in mushrooms serves as a protective agent, allowing them to endure fluctuations in their environment.

Some of the most popular edible mushrooms, such as shiitake, oyster, portobello, and enoki, contain notable amounts of trehalose. Shiitake mushrooms, in particular, are a standout source. These mushrooms, cherished for their rich umami flavour and health benefits, can provide a natural boost of trehalose when consumed. Foraging enthusiasts and those who enjoy wild mushrooms like chanterelles or morels can also enjoy the benefits of trehalose, as these varieties are known to contain significant amounts.

When mushrooms are consumed as part of a balanced diet, they offer not only the potential health benefits of trehalose but also a range of nutrients like fibre, B vitamins, and minerals. Their trehalose content contributes to their role in supporting immune function, cellular repair, and possibly even neuroprotection, although the latter is still being researched in human applications.

Seafood: A hidden source of trehalose

Trehalose is not limited to terrestrial organisms; it's also found in the ocean. Certain shellfish, such as shrimp, lobster, and crab, contain trehalose in their muscle tissues. Crustaceans rely on trehalose to help maintain cellular integrity, especially during stress conditions like changes in salinity or temperature. 

When it comes to human consumption, trehalose in seafood may offer some of the same protective health benefits, though its impact is likely more subtle compared to its use in medical or pharmaceutical applications. For those who regularly consume shellfish, trehalose can be an added bonus to the protein, omega-3 fatty acids, and other nutrients these foods provide.

Given that seafood is already recommended for its role in supporting heart health, brain function, and overall wellness, trehalose adds another layer of potential benefit, making these foods even more appealing for health-conscious individuals.

Bread and bakery products: Trehalose as a food additive

While natural sources of trehalose like mushrooms and shellfish are appealing, the sugar has also found its way into processed foods. In recent years, trehalose has been approved as a food additive in various countries, including the United States, Europe, and Japan. Food manufacturers often use it in bakery products, confectionary, and processed foods due to its stability, low glycaemic index, and ability to preserve moisture.

One of the key benefits of using trehalose in baked goods is its ability to improve the texture and shelf life of products. In bread and pastries, trehalose helps retain moisture, preventing staleness and keeping the texture soft for longer periods. This is particularly useful for packaged goods that need to maintain quality over time.

Additionally, because trehalose is less sweet than regular sugar and has a low glycaemic index, it's seen as a healthier alternative in some processed foods. It provides a mildly sweet taste without causing sharp spikes in blood glucose, making it an appealing option for diabetics or those looking to reduce their sugar intake.

Honey: A surprising source of trehalose

Though it is lesser-known compared to other sugars in honey, trehalose is present in trace amounts in certain varieties of honey. Honey, composed mainly of glucose and fructose, also contains small quantities of other sugars, including trehalose, which can vary depending on the type of honey and the plants from which the bees collect nectar.

While the concentration of trehalose in honey is relatively low compared to foods like mushrooms or seafood, honey is still a natural source where this sugar can be found. Moreover, honey is revered for its numerous health benefits, including its antibacterial and anti-inflammatory properties. The trace amounts of trehalose present in honey may contribute, in part, to its protective qualities, though more research is needed to fully understand this relationship.

Other potential sources: Algae and yeast

In addition to mushrooms and seafood, algae and yeast are other natural sources of trehalose that are gaining attention in the food industry. Algae, particularly spirulina and chlorella, are rich in nutrients and often used as supplements or food additives. Trehalose in these algae serves as a protective function similar to that in other organisms, helping them survive extreme environmental conditions.

For health-conscious consumers looking for plant-based sources of trehalose, spirulina and chlorella supplements or powders could provide a convenient way to incorporate this sugar into their diet. These algae are also rich in protein, vitamins, and antioxidants, offering a host of other health benefits.

Yeast, used in baking and brewing, also contains trehalose, though in smaller amounts compared to mushrooms or crustaceans. Some yeast extracts used as flavour enhancers or supplements might contain trace amounts of trehalose, which could contribute to their preservative effects.

The role of trehalose in food preservation

One of the most significant uses of trehalose in the food industry is its role in preservation. As mentioned earlier, trehalose's ability to stabilise proteins and retain moisture makes it an attractive ingredient for extending the shelf life of food products. This quality is especially important in frozen foods, where trehalose can help prevent the formation of ice crystals and maintain the texture of products like frozen vegetables, seafood, and meat.

In the beverage industry, trehalose is sometimes used in formulations of sports drinks and energy bars, where it provides a stable source of energy without the rapid spikes in blood sugar associated with other sugars.

Should you seek out trehalose-rich foods?

With trehalose gaining attention for its potential health benefits, the question arises - should you actively seek out foods containing this sugar? While trehalose offers some promising health benefits, it's important to remember that it is just one component of a broader diet. Natural sources of trehalose, such as mushrooms and seafood, can certainly be part of a healthy diet, but they also provide other valuable nutrients, making them worth including regardless of their trehalose content.

For those interested in reducing sugar intake or managing blood sugar levels, trehalose may offer some advantages over traditional sugars. Its low glycaemic index and ability to promote cellular health make it an appealing option for those with diabetes or metabolic concerns. However, the health benefits of trehalose are still being researched, and it should not be seen as a miracle cure.

Conclusion

Trehalose is more than just a natural sugar found in mushrooms and seafood; it's a compound with remarkable properties that has the potential to impact human health in numerous ways. As scientists continue to uncover its benefits, trehalose-rich foods could play an increasingly important role in our diets, whether for their neuroprotective effects, their role in metabolism, or their use in food preservation.

Renald Blundell is a biochemist and biotechnologist with a special interest in Natural and Alternative Medicine. He is a professor at the Faculty of Medicine and Surgery, University of Malta.

Photo: AI-generated image created by Prof. Blundell