Healthy or Hoax is a new podcast series from RNZ that looks at the new-fangled fads and tempting new trends and asks if they're really up to much. In short: Do. They. Work? Presented by Carol Hirschfeld, with help from food writer Niki Bezzant and a host of experts, the series will report on the latest things in food, fitness and leisure and ask if they're all hype or if they're actually good for you.

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Kate Pereyra Garcia documents her three weeks eating coconut oil in part one of Healthy or Hoax, a new podcast series looking at the facts behind current health trends. Does it live up to the hype?

By Kate Pereyra Garcia

The proponents of coconut oil make a lot of promises.

So when someone was needed as a human guinea pig for RNZ's Healthy or Hoax podcast, I volunteered.

Lose weight, lower cholesterol and prevent wrinkles? Simply by eating oil?

If it works: amazing.

The claims around the medical properties of coconut oil have burgeoned in recent times, with bold claims online that it's "one of the healthiest foods on the planet" with "life-saving" properties. Beyond the more superficial claims about weight loss, building muscles and stopping wrinkles, its supporters suggest it may prevent Alzheimer's, heart disease and some cancers.

If even half of the claims were true, it would be a miracle cure. So, although some scientists are pretty sceptical, it's not hard to see why more people are buying it.

New Zealand supermarkets had a 15 percent year-on-year increase in sales.

Countdown spokesperson James Walker said it was part of a trend across the entire supermarket for specialty health foods. For its part, Foodstuffs confirmed New Zealand supermarkets sold more than $7 million worth of coconut oil in the year to March.

So I was in good company when I popped into my local New World to purchase a tub for the experiment.

It was completely non-scientific, of course, but the idea was to consume at least a tablespoon a day for three weeks. I did a blood test to check cholesterol levels before and after.

Consultant Laurence Eyres conducted a major review of studies of coconut oil for the Heart Foundation, which was published last year in the Nutrition Reviews journal. He didn't find one peer-reviewed study showing any benefit of using coconut oil.

"The claims for curing Alzheimer's or cancer or what have you were based on marketing hype and had no foundation."

So on the serious science, there's no evidence to endorse the claims, though one Otago University study showed coconut oil wasn't quite as bad as butter when it came to raising cholesterol levels.

Auckland University of Technology Professor of Public Health Grant Schofield said coconut oil was not necessarily bad for you, but there was no evidence it would live up to the more extreme claims.

So how did my experiment go?

The first week was fine, I mainly used the coconut oil to fry vegetables each night. By the middle of the second week I was sick of stir-fried dinner and over everything tasting like coconut…

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Carol Hirschfeld hits the gym for some High Intensity Interval Training and finds it can take you up a notch... If you fit the bill. So is HIIT right for you?

By Kate Pereyra Garcia

Watch a video segment from the episode here

Anyone who belongs to a gym has probably done it. Even those who don't have probably heard of it.

High Intensity Interval Training (HIIT) has had a lot of media coverage in recent years for being a quick fitness fix for anyone short of time; which is pretty much everyone, right?

Even RNZ has discussed its benefits.

HIIT is essentially short, intense bouts of exercise interspersed with periods of rest. It's the antithesis of long steady cardio training. Some of the more well-known studies involve participants sprinting on stationary bikes for one minute intervals at a maximum pace versus slow continuous pedaling.

As the Healthy or Hoax podcast team, led by host Carol Hirschfeld, found out HIIT definitely has some benefits. The most obvious is that you can finish a workout in 20 minutes instead of an hour... or more.

Performance physiologist and AUT adjunct professor Paul Laursen said studies showed participants achieved as much, if not more, in the shorter time.

"You wind up being able to accumulate a greater amount of hard work than if you were just going to perform that same amount of work continuous.

"So by breaking it up you get a longer period total of high intensity work."

But, Dr Laursen warned HIIT is not necessarily as good as it sounds.

"Sometimes it's just interpreted as 'all I need to do is go out and kill myself', and of course we've all got pretty busy lives, we're under a lot of stress, sometimes we're not always on the healthiest diet, so there's loads of different stressors."

In that case, adding further stress in the form of high intensity exercise is asking for trouble, he said.

"You can really speed your way to over training... ultimately you can make yourself sick, or feel run down, and you can injure yourself as well."

One to three HIIT workouts a week should be the maximum, Dr Laursen said.

Les Mills head of research Bryce Hastings said the gym's HIIT classes were for people who already exercise consistently.

"You might be up to five days a week.. and when you've got that going and you're pretty comfortable there and people are wanting that next level of improvement - that's where we see HIIT as being really really useful."

The most important thing was to be moving consistently, he added.

Fitness instructor Chris Richardson is a HIIT convert…

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Greens powders are firmly entrenched as part of the smoothie craze, but in episode three of Healthy or Hoax we find out there's one ingredient in there you might not expect.

By Adam Macaulay

I usually have lots of fresh greens as part of my regular diet and you know what, I rather like eating them. So I volunteered when someone was needed to give greens powder a go for this Healthy or Hoax podcast.

The powder was supposed to give me concentrated greens, so I didn't have to eat the real stuff. In other words, it was the vegetable equivalent of a short cut; a cheat sheet.

But for me it's a question of palatability. Basically the powder tasted like ... well, it's not good.

When you put it in a smoothie it tends to combine with the other vegetables and fruits and produce a colour something like fresh concrete or, let's be honest, the poo of a sick baby. Worse, should you ignore the colour, close your eyes and just drink it, you could only taste the powder.

As to the health benefits, I was not convinced - certainly I didn't feel any better than I usually do, given my usual fairly healthy diet.

It also costs a lot. Obviously I wasn't partaking in a serious scientific experiment so it's hard to really gauge the benefits, or lack thereof. Using my mother's medical logic (or was it just a con trick): "It tastes awful so it must be doing you an awful lot of good."

However, Canterbury University Professor of Toxicology Ian Shaw said that was not necessarily the case.

"These plants are being grown in all sorts of different soils in different parts of the world... and they might contain other things that we don't expect them to contain, like arsenic."

Studies in the United States have shown greens powders there contained low levels of arsenic - a naturally occurring poison.

Dr Shaw said there was no requirement for risk assessment testing on greens powders sold in New Zealand because they're classified as a food, not a medicine.

"The risk is incredibly low.

"Arsenic is a carcinogen - it causes cancer - but only on long, long, long-term exposure. So what we try to do is keep our arsenic intake as low as possible for that reason, not because it's going to kill us stone dead, but because of the effects it may have in the long term."

Auckland University Professor of Nutrition David Cameron-Smith said there had been no research about the effectiveness of greens powders relative to their source ingredients…

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A raft of new dairy substitutes are turning up on supermarket shelves, but in part four of Healthy or Hoax we ask: can they really be called milk?

By Kate Pereyra Garcia

On the surface almond milk is a pretty innocuous, even healthy, alternative to dairy milk.

But the name - those two words 'almond' and 'milk' - raise all sorts of questions. For example, how do you milk an almond? Even the best Kiwi cockie wouldn't be able to tell you where to put the cups.

The fact is, almonds make up less than two percent of the average carton on the supermarket shelf.

What's more, technically it can't even be called milk.

Liggins Institute chair David Cameron-Smith says almond milk is, instead, a manufactured product.

"Milks as they're strictly defined as the product of mammalian reproduction and maternal care and so milk should really only apply to the secretions of mammals.

"Almond milks and the other milks that you can buy on the shelves are just simply white fluids that are given the name milk and they are not technically milks."

However, demand for dairy was still rising too, she says.

Food writer Niki Bezzant says demand for dairy milk alternatives is a growing international trend, with the global market set to reach $19.5 billion by 2020.

"is, in a way, more processed than dairy milk, it's got to be because to get milk out of almonds is not a natural thing."

Almond milk, and other milk substitutes, were often sweetened and were low in nutrients, unless they're fortified, Bezzant says.

"If you're lactose intolerant then yes, it's good for you, because it's helping you not to have these unpleasant symptoms that you get from dairy."

And if you're not?

"It's not bad for you, but you're not necessarily getting the nutrients that you would get out of dairy milk."

Consumer food writer Belinda Castles said almond milk was a triumph of marketing - far and away it's biggest ingredient was water.

"Some people would be quite horrified that some products only contain 2 percent almonds... if you made almond milk yourself, you'd get up around 12 percent, maybe 18 percent."

So how do manufacturers get away with calling it 'milk'? Castle says it's because there's no particular food standard covering that. What the Australia-New Zealand food standards do say is that "plant-based milk alternatives" are usually only able to match milk for nutrients by adding vitamins and minerals…

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Carol Hirschfeld gives flotation pods a try to see whether they could be an answer for those looking to de-stress.

By Kate Pereyra-Garcia

Watch a video segment from the episode here

On the surface, flotation pods sound a bit wacky: enclosed bath tubs with 30 centimetres of water and a lot of Epsom salts.

The water and room temperature are set at about 36°C - the average body temperature. You climb in, lie back and shut yourself off from the world, hopefully slipping into a state of mental and physical relaxation. At least, that's the idea.

The pods were created by American John Lilly, in the 1950s. He called them sensory deprivation pods.

He's a controversial scientist who took LSD and ketamine and also believed humans could speak to dolphins.

But Anton Kuznetsov, the owner of Auckland-based Float Culture, said he became hooked after his first float and decided to open his own business.

They're doing so well they're looking to expand, despite the $40,000 price tag of the float pods.

He said several of their clients have been with them for years.

"Others just say the weight of the whole world fell off their shoulders, they felt great for days after their float and it's just changed their life."

The scientific research on the potential benefits of flotation, however, is limited and, as Discover magazine puts it, "imperfect", given the small size of the studies done and the question over how to create a control group.

Do you control, for example, for light, sound, water or temperature? And without proper controls, it's difficult to know whether the benefits claimed come from the floating, or some other factor.

Back when Lilly was first experimenting in this area, it was described as the study of "sensory deprivation" and was associated with tales of attempts to brainwash or torture prisoners of war. But in the 1970s a new generation of social scientists renamed the experience REST (Restricted Environmental Stimulation Therapy).

But the conundrum remains. What for some is bliss, for others may be torture.

Despite claims of increased creativity, an easing of chronic pain and improved mental health, the research just isn't comprehensive. One study quoted as worthy of attention is a 2005 meta-analysis of 27 studies, which found floating was effective at reducing stress; seemingly more than relaxation exercises or slumping on the couch.

Col, a client at Float Culture, said floating had a huge effect on his pain levels and openness to life.

"It took me quite a few floats to actually get past that baseline anxiety and actually relax…

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Would you be better off eating food raw, rather than cooking it. I mean, who needs fire?

By Kate Pereyra-Garcia

Raw food advocates say food not heated above 40 degrees Celsius is more 'alive'.

A raw food diet is a pretty extreme way of eating for those of us used to cooking dinner every night.

The key word being cooking.

Raw food advocates believe in not heating food above about 40 degrees Celsius. They also tend to be vegan, meaning they don't eat any animal meat or byproducts.

It's a diet high in fruit, vegetables, nuts, and seeds.

Which certainly sounds healthy.

But Auckland University Professor David Cameron-Smith said there was no scientific evidence to support the idea that not cooking food was especially healthy.

"What current raw food relies upon is technology that's only been introduced in the last few years... so in the context of occasional food, raw food is fantastic; it opens up a whole new level of cuisine, it opens up paradigms around the use of things in completely different formats."

It was just another eating fad, he said.

Harnessing fire to cook was a "major leap forward for civilisation".

Cooking also makes things more digestible, and allows us to eat things we couldn't otherwise, Prof Cameron-Smith said.

Food writer Niki Bezzant said just because something was raw, didn't mean it was healthy.

"You're not going to lose weight by having a raw cheesecake instead of a cooked cheesecake," for example.

"The sweets and the deserts are the things that seem to get the most pick up... If that's the only thing that people adopt then they're probably not going to end up being that much healthier than if they just start to eat some more vegetables for example."

however, raw food advocate, and business owner, Megan May said eating raw helped her to recover her own health after she became burnt out.

She said she listened to her body to discover which foods worked for her and which didn't.

As a chef, she'd been eating a lot of things she now says she was intolerant to.

"It was amazing how quickly you could feel a little bit of life coming back into me."

Prof Cameron-Smith said an extreme approach to a raw diet could leave people at risk of becoming iron deficient, which affects mood and the ability to think clearly, but eating more fruits and vegetables was undoubtedly a good thing.

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It's been a long time coming, but the long-awaited second season of Healthy or Hoax is on its way with new host Stacey Morrison.

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