Functional fungi are the hot new thing in health and wellness circles. Many would say all fungi are functional, but in this case it refers to mushroom powders and supplements which some believe have a huge variety of benefits. 

In this episode of Healthy or Hoax, host Stacey Morrison investigates functional fungi.

Listen to Healthy or Hoax with Stacey Morrison

There are plenty of New Zealand-based companies getting in on the mushroom supplements game, offering products that claim to boost gut health and immune support, increase oxygen uptake and ease fatigue, and improve heart health and sleeplessness.

To find out more about fungi in general, Healthy or Hoax producer Liz Garton attended the annual fungal foray to talk to some mushroom enthusiasts, including Bevan Weir, research leader in mycology and bacteriology at Maanaki Whenua / Landcare Research.

Bevan Weir, research leader in mycology and bacteriology at Maanaki Whenua / Landcare Research. Photo: Bevan Weir via RNZ

Weir says there is no strong evidence for many of the claims around fungi supplements having amazing healing powers.

"But there's a lot of active research going on, so yeah, there's there's always the possibility," he says.

Weir says even if you take out the unproven health benefits, mushrooms are good for you, especially if you're using them in place of meat products with high levels of cholesterol and animal fats.

"We really don't know if you're thinking about any sort of like specific activity, but I think mushrooms in general are just a really great thing.

"If you can build it into meals and eat it and if it has some great effects as well, that's just a bonus."

Alexander James Bradshaw from the Natural History Museum of Utah, who was in Aotearoa doing postdoctoral research, also attended the foray.

He says it's likely there are many medicinal compounds in a wide variety of different mushrooms. Lion's Mane mushrooms, for example contain chemical compounds called hericenones and erinacines.

"They are starting to come out in the literature as possibly being neurotropic, so actually having the ability to make healthier brain connections," he says.

Fungal Foray, 2023 in Maungatautari / Sanctuary Mountain. Photo: RNZ

But he warns that the research is in its infancy. And although many companies are already capitalising on the early findings, their claims should always be taken with a grain of salt.

"My biggest problem with many of [the supplements] is that they are often sold as panacea."

Dr Michael Howard practices emergency medicine in Northland and has a PhD in microbiology and immunology. He hopes that the folklore around mushrooms will soon be proven by science.

"Practicing in New Zealand, I've been impressed at the knowledge of your local providers.

"There is every month coming out another article that has scientific basis and is talking about the use of these things, particularly as an adjunct to cancer therapies and they're finding them to be safe and healthy and helpful

in those situations. So I'd encourage people to talk to their doctor," he says.

Unless they have been cut unethically with something dangerous, mushroom supplements are unlikely to he harmful, Bradshaw says.

"At minimum. I don't think anyone is going to be hurt by them."

In the name of science, Stacey decided to try Flow State Lion’s Mane capsules ($55 for 120 capsules), which claim to provide brain health support.

She took one capsule every morning, which made her feel more alert. Could this just be the placebo effect?

Professor Clare Wall, head of the department of nutrition and dietetics at the University of Auckland, agrees the placebo effect can be super powerful.

"They say around 17 percent effect, actually. I mean, maybe it has given you some benefits, you know, whether that be placebo or active," she says.

Looking at fungi as a whole food, Wall is a fan.

"Mushrooms have got a great nutritional profile so they give you a good bang for your buck," Wall says.

"They're very low in energy and quite a lot of them that provide lots of nutrients. They've also got some very strong antioxidant properties as well."

Professor Clare Wall. Photo: Supplied via RNZ

Historically there have been lots of studies looking at the nutritional benefits of mushrooms and population studies looking at groups that culturally consume mushrooms regularly. Some show that populations that consume

more mushrooms in their diet have reduced risk of certain types of cancers, particularly breast cancer and also some neurodegenerative disorders.

"But we can't say yes, if you eat mushrooms, you are definitely going to reduce your risk of getting cancer or you're definitely going to reduce your risk of getting Alzheimer's, because those studies can't give us causality," Wall says.

She has only seen small trials done into mushroom-type supplements versus placebo and looking at the impact on some immune markers and anti-inflammatory markers rather than any long-term trials where those supplements have been used to demonstrate reduction of risk of cancer, Alzheimer's or Parkinson's diseases.

"Often the the claims are what we call quite soft," Wall says.

"So they're saying that this product contains a substance that's found in mushrooms that has been shown to be beneficial for your health. But they’re not actually saying, 'if you take this supplement every day, you are definitely going to reduce your risk of getting neurodegenerative disease or you're definitely going to be sharper and you can perform better'. There's no direct association. They shouldn't be making that kind of claim."

Mushrooms are a versatile and nutrient rich option, according to Dr Clare Wall. Photo: RNZ

If you do want to add fungi to your diet, Wall says the literature suggests the antioxidant levels are higher in raw form.

"Apparently grilling is the most effective way of retaining them. And the longer you cook them for and the more water they're exposed to, then the more likely the reduction in the antioxidant properties. But they still do retain

some of the antioxidant properties."

The concentration of antioxidants varies greatly, depending on the type, how they're grown and when they're harvested, she says.

Wall's final advice on mushroom supplements is simple: "first do no harm."

"If it benefits you, that's fine. If it doesn't, it's kind of a waste of money. But as long as it's not going to do you any harm, that's the most important thing."

She herself would not take supplements.

"For me there's no convincing evidence for me to take them. I'd rather eat them in their whole form."