- This week on The Check Up ` placebos have no active ingredients. - So why do some patients report relief after receiving it? - Jayani's on a chronic case. - There's one condition that continues to challenge the medical profession worldwide. - Sean gets activated. - Charcoal's definitely in hot demand, but what's the reason for all the buzz? - But first, would a rose by any other colour smell as sweet? (UPBEAT ACOUSTIC MUSIC) - We've all heard the song 'Red, Yellow, Pink and Green'. We may be able to sing a rainbow, but what about seeing a rainbow? Is my red your red? My blue your blue? How do we know if you're seeing the colours I'm seeing? Are we all colouring with the same box of crayons? When he wasn't giving us the lowdown on gravity, Isaac Newton also discovered that white light is a mixture of different wavelengths.' Colour depends precisely on which wavelengths of light are reflected from objects and transmitted to our eyes. At the back of our eyes, we have two types of light receptors ` rods which work in low light conditions to help night vision and cones, which are our daytime colour receptors. There are three types of cone cells. One perceives red light, another green light, and the third blue. When they all work together, most of us see a whole spectrum of colours. Some estimate 10 million all up. It's a fault with these cone cells that can cause some people to be colour-blind. (UPBEAT ACOUSTIC MUSIC) - I was about 11, and I was at intermediate school, and they ran a few basic tests just to test your vision, and that's when I discovered I was colour-blind. It fascinated my friends. I remember them being really interested, and, you know, the first thing you get is, 'What colour is this?' And, 'What colour is that?' Everyone's interested in what you see. I work as a architectural visualisationist. Being colour-blind means that I often have to ask for a bit of help here or there if I'm trying to colour match or do something like that. Contrast is a big thing. I'll put one colour next to another just to see how it stands out against something else. - Colour deficiency is much more common in men than women. This is because in the majority of cases, it's a genetic condition passed down on the mother's X chromosome. If you're male and there's a history of colour-blind men on your mum's side, there's a good chance you will be too. Women are often carriers of the gene, but to be colour-blind themselves, they must inherit the condition on both X chromosomes. For the vast majority, being colour-blind doesn't mean the world looks like this. It could look like this. This. Or even this. The most common forms of colour-blindness are reduced sensitivity to either red or green. - I'm red-green colour-blind. So it's red that's really muted to me. From a distance, especially, it kind of just all blurs in, just looks like one colour. Public bathrooms, they'll often be red-green, and you don't know if the door's engaged. I have to peer at the lock and kind of awkwardly knock on the door. Fashion can have its moments. I bought a red pair of pants that I thought were brown. I'd wear a lot of pink when I was younger. When you work it out, you feel pretty silly. - To find out if you're colour blind, a number of tests are available. The most well-known are the Ishihara plates. Designed by a Japanese ophthalmologist over 100 years ago, these reveal numbers and patterns to those with different levels or types of colour-blindness. I can see squiggles here, whereas those who are colour-blind might see numbers. With this number 35, someone with a green deficiency would only see a three whereas somebody with a red deficiency would only see a five. There is no cure for genetic colour-blindness, but there is developing technology that could offer a helping hand. - A couple years ago, my friends all chipped in and bought me this pair of glasses for my birthday. Pretty special. They help you see colour if you're colour-blind, obviously. - The glasses don't offer normal colour perception, but may add new shades and hues. The degree depends on the type and severity of the colour blindness. - Certain roses or, you know, they normally look quite similar. The orange and the red and the yellows just really pops. You can see a big difference. The subtleties in the greens and the way it transitions between the green and the red. You might miss that before, so it really helps you see kind of things like this. There are times that you wish you weren't colour-blind. You're buying a gift for someone and you pick up the wrong colour. But it's never a major. It's just subtle. But I definitely` You know, you do wish you sometimes didn't have it. (LAUGHS) (UPBEAT MUSIC) - Barbecuing is a favourite Kiwi pastime. For many serious backyard barbecue enthusiasts, charcoal is the only way to go. But should barbecuers beware? Charcoal as in hot demand. This carbon residue is being added to things we eat ` charcoal cocktail, anyone? ` skin products and health supplements. So what's the reason for all the buzz? The first thing to note is that the charcoal you use to fire up your barbecue is not the same as the stuff that's making headlines. So don't try putting it in your mojito. Activated charcoal powder is specially manufactured to increase its surface area, which makes it extremely absorbent. By adding some activated charcoal to this grape juice, I can show you how it works. Each particle of activated charcoal has tiny holes and crevices ` a bit like a sponge or dimples on a golf ball. These holes make it more porous, which adds up to an incredibly high surface area. It's amazing. The activated charcoal actually absorbs all of the colour from the grape juice. It still smells like grape juice, but does it taste like it? (LAUGHS) It genuinely does! Traditionally, activated charcoal has been used like a kind of super soaker to remove unwanted chemicals or minerals from our drinking water or to absorb accidentally ingested poisons in our gut. In typical human fashion, many have jumped on the activated charcoal bandwagon. Trendy food supplements claim to act as an all-purpose detox, beat bloating and even cure a hangover. The reality is our body's liver and kidneys are far more effective at removing environmental toxins than anything we add to it. Unless you've been poisoned, there is no evidence that charcoal will help detox your body or stop gas. As a hangover cure, it fares no better. Alcohol is absorbed quickly into the bloodstream, so activated charcoal in our gut hardly gets a chance to make any impact. In food, activated charcoal is certainly eye catching. It's said to add a smoky umami flavour, but it won't improve your health. In fact, ingesting it could do more damage than good. Not only does it have the ability to absorb prescription medicines, but it could also remove valuable micronutrients needed by the body. As for the growing number of activated charcoal skincare products on our shelves, there is no evidence that they're going to do anything regular skin care wouldn't. Jet black cocktails, crackers, face masks ` they sure do make for a good Instagram photo. (CLICK!) But the idea of using charcoal on the quest for wellness appears to be a burnout. Perhaps it's just best we leave it to the barbie. - Chronic fatigue strikes young and old, fit or not. - I've gone out of really tough situations. This was probably the toughest one I ever had to go through. * (UPBEAT OLD-TIME PIANO MUSIC) - Nowadays, we are hyper aware of the need for good hygiene. But it wasn't always a given. Back in the day, even doctors didn't get the link between bacteria and disease and would happily finish up an autopsy then get to work on their next patient... without washing their hands! Ew! When it comes to human health, we've made incredible advances through the years. But there's still so much we don't know. There's one condition that continues to challenge the medical profession worldwide. Dr Rosamund Vallings has specialised in it for over 35 years. - Pockets of people were diagnosed with different things in different parts of the world, often following some sort of infection. And so it was labelled Tapanui flu in New Zealand. There's Icelandic disease, Royal Free disease, Los Angeles epidemic. And the first conference I went to, which was in about 1978, I think, um, all these doctors from around the world beginning to realise that what they were talking about was all the same thing. And it began to be labelled chronic fatigue syndrome, or in some countries, they call it ME ` myalgic encephalomyelitis. - Sports star Richie Barnett has represented New Zealand in rugby league and played professionally all over the globe. But nothing could prepare him for his chronic fatigue diagnosis. - I've been through adversity before. My face now is reconstructed. I've got 10 plates in the there through an injury playing rugby league. You know, intensive care for seven days. And I've got out of really tough situations. This was probably the toughest one I ever had to go through, because there's no` there's no answers to things. We thought we were going crazy. - That was the worst time before the diagnosis, not knowing what it was. And we couldn't understand why, you know, these medical professionals couldn't tell us what was wrong. - Part of the difficulty of pinpointing chronic fatigue, or ME, is that the symptoms differ widely from patient to patient. - The commonest symptoms will be difficulty with exercise. People find that they are often highly motivated to do exercise, but if they push beyond A very minimal amount, they get a worsening of all symptoms and often feel very, very ill. They get a lot of muscle aches and pains, headaches. Uh, many people get sore throats and glands up as signs of an immune system in overdrive. And a lot of people will say the worst symptom is brain fog, where they get this kind of cognitive difficulty; they cannot concentrate for very long. - Physically, it stripped away my essence of who I am as a character of a person ` energetic, ready to go, attack everything, positivity. Since a young kid, that's what I've always been about. It emotionally affected me, cos physically I was drained and fatigued ` frustration, depression. I lost my purpose. Unsure. - Chronic fatigue strikes young and old, fit and not. In fact, those that push themselves very hard, whether in work, study or sport, are a particularly at-risk group. It often follows a viral infection like flu or glandular fever. But in some cases there also appears to be a genetic factor. In New Zealand, thousands of people suffer from chronic fatigue syndrome, but due to its complex nature, the illness is often misunderstood and regularly stigmatised. - It's really hard to explain what chronic fatigue is. And, you know, people are like, 'Well, you're tired. So what? I'm tired all the time. 'Like, you know, get up and deal with it. You know, harden up, toughen up.' That was sort of the perception that people have. And I think people still have that perception today. It's very misunderstood. Mm. - In my mind, it was better off not saying anything. I've got this condition. I have to deal with it and just forget about the perceptive views of people, because it's just too much. - Despite being notoriously difficult to diagnose, there are ways to combat chronic fatigue. - Setting up a management plan's important. Medication is sometimes helpful for sleep and certainly for pain. And sometimes we use medication to help prevent some of the symptoms of what we call POTS, which is very light-headed, tendency to feel very faint easily because of a very low blood pressure. Uh, for those people, extra salt in their diet can make a really big difference. There is some evidence as to how and why B12 could help, and there will be perhaps up to about 70% of people who do benefit from B12. So there are kind of a lot of management strategies, but you have to tailor it for the individual, really. - There is hope. There's resources out there for people to tack into. The trainer that I had who was aware of it, actually, which was outstanding, he said, 'You should do things that you really like more often.' So a strategy that I had early on was going to the gym only for five minutes. If that was to make me happy with the endorphins, I'd go and do it. In my head, it felt great. Just even if I walked in, did one press up and just walked out and then had a coffee, that's fine. - It's difficult to diagnose and tricky to treat, but sufferers of chronic fatigue should be rest assured that there are now professionals on the case investigating this debilitating condition. - Sham treatments have been around as long as time, but when is a sham not a sham? When it's a placebo. - There are plenty of legends claiming to cease the flow of onion-induced tears. VOICEOVER: Your spare pair, your glare pair, the flying-through-the-air pair. We could all use a second pair. (WHIMPERS) At Specsavers, get specs and shades for $169, including single-vision lenses. * (PENSIVE MUSIC) - Odd treatments have been used throughout the history of medicine. In ancient Egypt, patients were treated with lizard's blood, crocodile dung and pig's teeth. In the 18th century, Europeans downed earth worms, woodlice and even powdered mummy, thinking it would improve their health. Dodgy cures and sham treatments have been around as long as time. But when is a sham not a sham? When it's a placebo. A placebo is anything that mimics a real medical treatment... but isn't. In one case, 117 volunteers with back pain were given a pill filled with rice for three weeks. Told it was a painkiller, almost half of them reported significant relief from their pain. Whether it's a pill, a shot or some other kind of relief, a placebo has no active ingredient. So why do some patients report less pain and improved symptoms after receiving it? Experts believe much of a placebo's success has to do with expectation. If a patient believes a treatment to be real and they expect to feel better, it may happen. If they expect to suffer side effects, they may get them. If a drug's worked on previous occasions, they expect it to work again. The strength of the placebo effect has a lot to do with how we expect to get relief. The medical rituals, the environments that surround treatment. Which doctor do you trust the most? Or which pill will work? The one that looks like a pill or the one that is obviously lollies? If we believe we're getting a lot of care, attention and empathy, we're more likely to believe our treatment is working. In some clinical trials, a placebo has been noted to have real effects, sometimes as great as the accepted drug treatments. Placebos are used as an integral part of medical research. I'm meeting Professor Wayne Cutfield at the Liggins Institute to get the lowdown. - Clinical trial is an evaluation of the impact of a treatment. Often it's a medication, but not always. And it's to understand the value or the impact that has on our wellbeing and our health. - To do this, trial participants are split into two random groups. One receives the placebo and the other receives the active treatment. This means researchers can evaluate the treatment's actual effectiveness versus the patient's expectations. Who gets the treatment or placebo, however, must remain a secret. - We call that blinding. The participants are blinded. So if they knew they were receiving the placebo, they would react and respond differently to those who are getting the treatment. We also blind the researchers because it could change the way they behave with participants. They may be more animated, more positive. They might make subtle suggestions or cues about responses to treatment. You know, it's the frailty of human nature. And I'd have to say researchers are not necessarily good poker players. So there is the risk that they will kind of lead the participants into responding a certain way. - And that's a double blind study. - And that's a double blind, randomised, controlled trial. - Could there be a biological effect from the placebo? - Yes, there can be. There are areas of the brain involved in emotion and behaviour that are activated after taking a placebo medication. And that's part of that whole expectation response. - And how would that affect you physically? - It can increase your sense of well-being. It can change heart rate, blood pressure, dampen down pain and pain response. So they can be quite significant biological effects. It's important to note that while placebos may relieve some symptoms and side effects that come with illness, they will not cure the problem. They won't lower your cholesterol or shrink a tumour. - Can the appearance of a placebo make a difference? - Yes, it does. And in fact, there have been studies that suggest, for example, the colour of a placebo makes a difference. If the desired effect is to have a positive stimulatory effect, then red, orange, yellow coloured tablets or capsules are more likely to be effective. Conversely, if the effect is to have a much more sedating, tranquillising, calming effect, then blue or green capsules or tablets are more likely to be effective. Uh, bigger tablets and capsules are thought to be more effective than smaller ones, and capsules more effective than tablets. So the preparation does make a difference. - Way back in 1572, the French philosopher Michel de Montaigne observed there were those on whom the mere sight of medicine is operative. And modern science is proving that the power of placebo is just as potent as the ancients believed. (UPBEAT MUSIC) - There aren't many things that can turn me into a blubbering mess but injured puppies finding their forever homes, a movie with a happy ending... and onions will do it every time. Almost every one of my favourite recipes starts off with a finely chopped onion. But sometimes even the thought of it reduces me to tears. Is there any way to get through chopping these with dry eyes? There are plenty of legends claiming to cease the flow of onion-induced tears. Chewing bread? Sounds weird, but I'm willing to give it a go. So apparently chewing bread makes you breathe through your nose instead of your mouth. Now, what that has to do with your eyes, I'm not quite sure. But I can definitely feel myself tearing up now. (CURIOUS MUSIC) (ONIONS CRUNCH) So lemon is meant to be a powerful odour absorber, but clearly it's just not working for me. What about lighting a candle? So the idea of this is a candle flame's meant to draw away the fumes. Maybe romantic, but it's not doing much else. So why does cutting onions make us cry? When we cut onions, we trigger the self-defence system... and a chemical reaction occurs. An enzyme is released which reacts with the amino acids in the onions and forms a sulfenic acid gas. Our eyes have a set of nerves that detect anything that's potentially harmful to them. They react to the gas and try to flush it out with tears. It's annoying, but as we all know,... it's only a temporary nuisance and it won't have any long lasting effects. But there's one more tip I'm willing to try. Freezing your onion for 30 minutes before cutting slows the release of the gases. It makes it a little bit harder to cut... And besides my fingers going a little numb, I'm not crying. A sharp knife also causes less cell wall damage and fewer chemicals are released. Unfortunately, I've got a lot more onions to get through ` and none of them are frozen. So it's time to bring out the big guns. This way I can save my tears for when Adele drops her next single.