You're listening to Science Versus, the show where we pit fat against fat. I'm Wendy Zogumen, and on today's show, The Sugar Free Diet. Is sugar really sweet, sweet poison? These searches have been salivating a breakthrough.
And you repeat this count when you're in the country. And covering the sinister secrets. Digest across the world. The idea behind these sugar-free diet is that you should avoid processed sugars because there is something especially bad for your health.
Even toxic about sugar when you compare it to other unhealthy things like fat and salt. I was a coke-swilling pizza eating cigarette smoking kind of guys like 20s. This is Damon Gemma. And a few years ago, in a video to impress a lady, he removed added sugar from his diet.
And quickly, he says, things started changing. I just kind of noticed the difference. I changed quite physically in terms of my weight, people started commenting, which is handy because I had an active video. And then my moods basically changed.
I felt a lot more even and consistent throughout the day. Damon was so excited about the changes that he felt he made a movie and wrote a book about it. So my name is Damon Gemma, I'm the writer, director and producer of that sugar film, and we offer a fat sugar book. Sugar is now found in 80% of the foods we eat.
But with the constant sugar, isn't just making us fat, but when it comes to fatty livers and type 2 diabetes? Sugar is a major, if not the major, player in all these symptoms. And in making these claims, he's not alone. Sugar is driving all of the chronic metabolic diseases that we know about today.
It's slowly killing us the more I learn about it, the more it scares me. As addictive as the hottest of illicit drugs. You don't worry, that just sounds a little bit over the top. Sure, but it's the truth.
Serious new warnings from serious people. But that's all fine, but then there's science. Well, some of those voices you just heard actually came from scientists. Yes, they're the serious people.
So let's try it very carefully here, and start nice and slow. These days, the World Health Organisation is recommending that for optimum health, people don't eat more than 25 grams or around 6 teaspoons of added sugar in a day. And that doesn't include sugars from fruits and veggies. So, what's the problem if someone eats too much sugar?
They store more fat, and they may or may not increase body weight, but they certainly store more fat within the body. That's Dr Kieran Rooney, a nutritionist at the University of Sydney. And he says it's not just fat on the body that you can see, which is the problem. Excess sugar also leads to fat swimming around your blood.
That is highly correlated with cardiovascular disease and heart problems. He also says... Animals who are being overfed high sugar diets will also develop indicators of glucose intolerance. And this is a preliminary step on the way to diabetes.
But the big question, does eating excess sugar cause these problems? Or is it excess calories in general? Well, a calorie by definition is the amount of heat needed to raise the temperature of 1 gram of water by 1 degree Celsius. So, if you're trying to lose weight, doesn't matter if you get your calories from a cookie or a piece of steak.
Ah, very good question. There's a raging debate about our all calories, the same. That's Sandra Capra, a professor of nutrition at the University of Queensland. So, are you, does a calorie from protein mean the same as a calorie from a carbohydrate or a starch or a sugar or a fat, for example?
And the answer is, in terms of weight, no, there's no difference. And this is Professor Peter Clifton at the University of South Australia. Here, great. So, it's nothing magical about sugar per se.
But Dr Kieran Rooney isn't so sure. He says there are no studies that definitively show that when it comes to weight loss, a calorie from sugar is the same as a calorie from protein is the same as a calorie from fat. It's extremely difficult to be able to isolate the difference between whether it's the sugar that individuals are eating or whether or not it's the calories that are bringing with it. So, what study do we need to do to work this out?
You need to overfeed an individual. So, there's limitations in those studies because, you know what? We don't have funding and you don't get ethics approval to overfeed an individual small amounts of sugar for extended periods of time. You're not up for it?
I'd be up for it. But it'd be very hard to convince the National Health Medical Research Council to give me a few million dollars to do such an experiment. And it'd also be extremely difficult for me to get an ethics administration board to say, yes, knowing that there's a good chance overfeeding this individual could make them overweight, tired, diabetic, with cardiovascular disease, highly unlikely I'd get approval to do such a study. But luckily, we can do it with little rats.
But even then, the limitations is time. And so what you'll often see is short-term studies. Right. So it's not clear where the calories from sugar are especially harmful, but there's more to this picture.
A problem with sugars is that they tend not to fill us up as much as eating proteins or even fats. So we eat more of them, which means more calories, which is definitely problematic. And if you're guzzling liquids like soft drinks or even chocolate, which is considered a semi-soli because it melts quickly, you're even less likely to feel full. And it's not just hunger that's driving us to eat sugar.
Sugar's tasty. So we eat lots of it. Plus, according to the iQuit Sugar website, which is founded by Sarah Wilson, when it comes to eating sugar, moderation is impossible because, quote, two major studies have shown sugar to be as addictive as cocaine. End quote.
But as the iQuit Sugar website acknowledges, these major studies were conducted in animals, rats, to be specific, not humans. They also went particularly major studies. So when it comes to people, is sugar really more addictive than illicit drugs? Yes.
Well, I'm just a bit skeptical about that. This is Professor Bob Boox, a psychologist who works with Keir and Rooney at the University of Sydney. Well, there's no real withdrawal effects to start with. I mean, compared to going off heroin or whatever, it involves a bit of craving.
Obviously, if that's part of your diet, you like sweet things and sweet foods and sweet drinks, and you miss them a bit, and you think, oh, it's been nice to have a sweet hit. But the idea of addiction? The idea of addiction is a bit overplayed and old. Conclusion.
Eating too much sugar can make you fat, but the jury is out on whether sugar is the bad guy here or it's the excess calories. And even if all calories are created equal when it comes to weight gain, what about diabetes and heart disease? Well, Dr. Keir and Rooney says there is evidence from small, often short-term studies demonstrating that sugar in particular is associated with these diseases.
But if you look at population-wide studies involving thousands of people, things get complicated. Now, there have been statistical methods by which people have attempted to identify that is specifically the sugar molecules. And those papers have been published recently. But that data is very dirty, right?
There are lots of confounders. So what he means is that scientists can't be sure that any increase in diabetes or heart disease that they found was due to the sweet stuff. It could be due to other things in people's diets or their lifestyles. Now, so far we've been talking about sugar as if it's just one thing.
It's not. It's a family. There's fructose. Found in fruit and corn syrup.
Glucose also found in fruit. And when we break down starch, it becomes glucose. White as song? This is Aubrey by Bread.
The band's name is Bread. And when you break down starch, you get glucose. It works. Just make a coconut song.
There's sucrose, that's table sugar, which is actually made up of one fructose and one glucose molecule. And finally, there's lactose, which is in your milk. When it comes to our health, are all these sugars the same? Here, another debate is raging.
Some scientists, most famously Professor Robert Lustig at the University of California, say no. They are not the same. Believe me, they're not the same. He points his finger at fructose as the sugar, demon.
So I stop playing lime in the cricket? Just one more time. Chronic fructose exposure alone. Nothing else causes this thing we call the metabolic syndrome.
Everybody knows what the metabolic syndrome is. This is Professor Lustig speaking at the University of California back in 2009. We requested an interview with him, but he was busy. OK, so this is the conglomerate of the following different phenomena.
Obesity, type 2 diabetes, lipid problems, hypertension, and cardiovascular disease. Now, the idea behind demonizing fructose in particular is that our body doesn't use fructose in its fructose-y form. Cells like to deal in glucose for energy. So to handle that fructose, the body sends it to the liver, where lucky for us it can be converted into the very handy glucose.
But if your body has enough glucose, then the liver will convert that fructose straight into fat. Because what the liver does to fructose is really unique. Professor Lustig argues that this fat builds up in the liver and the blood, kicking off a nasty process of inflammation and the beginnings of diabetes and heart disease. Indeed, a study published this year by Dr.
Kimba Stanho at the University of California, found that drinking around half a can of soda sweetened with high fructose corn syrup, with breakfast, lunch, and dinner over just two weeks could increase the level of fats in the blood. Now, this is all sounding pretty bad for fructose. But before you put your fruit down, and definitely don't put your fruit down, we'll get to that in just a second. A Q&A recently published in BMC Biology concluded that for healthy individuals, quote, there is no evidence, however, that fructose is the sole or even the main factor in the development of these diseases, nor that it is deleterious to everybody, and to it.
And that's probably because if you eat too much of any sugar, your liver can also convert that into fat. So let's hear from the... This is Dr. Kimba really again.
Our animal data, that's looked at maltadextrin, it's looked at glucose, it's looked at sucrose, and looked at high fructose corn syrup, equivalent mix. I've seen that repeatedly. If you're going to overeat any sugar, you're going to see fatty livers. You're going to see increased body fat.
Plus, none of the experts I spoke to recommended restricting fruit to avoid fructose. Any health professional would be telling you that we should be getting our sugars from fruits, vegetables, and dairy products. Eating fruit is packaged with important fiber, which means you'll feel fuller when compared to eating chocolate or soft drinks. So you're less likely to fall into that trap of eating more calories.
Fruits also bring along important nutrients needed for living, such as minerals, vitamins, and antioxidants. So apples, bananas, just enjoy. Conclusion. Fructose might be a little worse for you than glucose, but overeating any sugar is a problem.
Now we're going to do a rundown of some other big claims made about Little Sugar. So going back to Damon Gammo, creator of that sugar film, he says that once he stopped eating added sugar... My mood's basically changed after a lot more even, consistent throughout the day. The iQuit Sugar website also says that, quote, sugar causes mood swings, end quote, and they say that sugar can leave kids hyperactive and grumpy.
But according to Professor Sandra Capra... Ah, no. If you take a huge sugar hitch, if you wish, your body pumps out insulin in response, trying to manage the transport of that sugar. And then a few hours later, you can have the crash, as too much sugar has been moved out of the blood, and then you get the low and the feeling of loss of energy.
That's quite true. But mood swings? Mood swings, where you might feel depressed or happy to later. No.
Professor Bob Bokes is also skeptical. There's much evidence for sugar causing mood swings. And he puts any seeming effect down to people's belief that consuming sugar has an important impact on their mood. This is also called the placebo effect.
I don't know if any good studies that show that glucose levels are really controlled mood. And I mean, one good example of this, this kind of the strength of belief is claims that high sugar loads make kids hyper. And that's very strongly believed. But when it's been seriously investigated, there's no sign that that happens.
We asked Sarah Gelson from iQuit Sugar Front interview, but she was unavailable. And when I asked the team to send me their sources about why they think sugar causes mood swings, they sent me one study from 1985, which involves four people, and some now outdated references in its introduction. They also sent me a report which found links between schizophrenia, depression, and the high consumption of sugar. And that's quite different from mood swings in the general healthy population.
Now, there is ongoing work into the links between mental illness and high sugar consumption, but there's no clear conclusions just yet. So scientists haven't knotted out whether any links they find are due to a poor diet in general, so not getting enough nutrients, say omega-3, this sort of thing. And scientists don't even know if sugar is causing a problem, because it could be that people with depression eat more sugar, because it's comforting. Other claims about the sweet stuff from the iQuit Sugar website, sugar accelerates aging and, quote, encourages wrinkles, end quote.
And Dr. Kieran Rooney says there is some indirect evidence for the aging thing, because there's an association between aging free radicals and oxidative damage within the tissues. And we know the metabolism of sugar results in production of free radicals and oxidative damage. But he also says, free radicals will be reduced when you're metabolising most foods, and you can also produce them during exercise, for example.
iQuit Sugar also says that sugar upsets the mineral balance and increases the acidity in your body. Oh, my goodness. He is Professor Sandra Capra again, and she's kind of summing up a lot of these claims. These are extrapolations from real science into what you might call speculation and comethology.
Dr. Kieran Rooney is a little more forgiving. We need to appreciate that the literature base, the evidence, the science, the results, the experiments that people conducting is forever evolving. Now, the question is, does one or two studies in an area make enough evidence to make a grand claim?
And while it's only one or two pieces of evidence, then the scientific community would say, no. So when it comes to science versus the sugar-free diet, does it stack up? It's going to take care of you. Eating too many calories are bad, and it's really easy to eat a lot of calories from sugar, because they don't fill you up and they're really yummy.
Whether sugar is worse for you than fats, the jury is out, it's looking like maybe, and whether fructose is worse for you than glucose? Well, perhaps. But when it comes to these debates... The bigger fish the fry.
In a world where almost 40% of adults are overweight and 13% are obese... At the moment, in our society, we're overeating. As for wrinkles, addictions and mood swings, there really isn't enough evidence for those. So when it comes to science versus the sugar-free diet, that's science...
One, I guess, because it's a work in progress here. And the sugar-free diet? Let's give it a one-two, even though those wider claims are bunk, not eating any cakes, cookies and processed sugary foods is definitely good for your health. That's it for science versus a big thanks to my co-producer, Caitlin Sore, and you can subscribe to us.
We are a podcast. So you can absolutely subscribe to us, and you should on iTunes or your favourite podcast app. You can listen to us on SoundCloud as well. Next time, medical marijuana can pot, heal cancer.
So far, there's a lot of laboratory evidence that stands up very well. You know, there's evidence to show that various of the cannabinoid substances can really inhibit humigrowth. I'm Wendy Zukamin. Back to you next time.