Welcome back to the Bite Me Nutrition podcast. Before we get stuck in, I'm sorry if it's a bit extra echoey, I've gutted my office. I'm doing some things to it, which is exciting, but it also is echoey because it's now just a big box. So hopefully it's not too bad. But I promise future episodes well, maybe not in the near future, but future episodes will get better. Anyway, we're not here to talk about that. We're here to talk about Aspartame, or aspartame. I don't really know how to say it. I'll probably say Aspartame, and thanks to my stupid Australian accent, the T will slowly become a D. But this chemical has been getting lots and lots of airtime recently. I'm sure you've probably seen lots of newspaper or online news articles with headlines saying the who the World Health Organization has labeled aspartame as a carcinogen. So a carcinogen is just a compound that we believe promotes cancer. So it increases your risk of cancer. Now a few things to unpack here, which is what we're going to do. Firstly, aspartame is an artificial sweetener. That is basically it's about 200 times sweeter than sugar. So what that means is we can replace sugar in something with something like Aspartame, but we use very, very little Aspartame because of how sweet it is, right. We don't need to use anywhere near the same amount as we would say, sugar. And so that's why you're going to find it in things like Coke Zero or Pepsi Max and things quote unquote, zero calorie drinks. And you also might see it in other diet products that still contain calories from other things. But by swapping, say, sugar to Aspartame, they lower the energy content. So you'll either see Aspartame listed as an ingredient or you might see the chemical sorry, not chemical, you might see the code e nine five one. Okay, so that's aspartame that's what it is. That's where you can find it in terms of this new report from one department of the World Health Organization. Right. So it's important to note actually, I've forgotten what the acronym is. I know it's IAC, but it's the International Agency for Research on Cancer. So they were the first ones that they've come out with a report and they've labeled it as a two B carcinogen. Right? So there's different classifications of carcinogens. They don't necessarily reflect how carcinogenic something is. What they reflect is how confident we are that they are carcinogens. So a one A carcinogen may not be more carcinogenic. I e may not cause cancer any more than a two B carcinogen. It's just that there's a lot of evidence for that one a carcinogen. We got lots of studies. We're confident that, look, this does increase cancer risk to some degree. Okay? So firstly, Aspartame has been labeled as a two B carcinogen, which I'm pretty sure is like the lowest level of confidence that we've got. Less confident is we're not labeling it. And so that's two B. And I'm going to read to you exactly what IARC describes, how they describe their two B classification. Right? This category is used for agents, mixtures, and exposure circumstances for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals. It may also be used when there is inadequate evidence of carcinogenicity in humans, but there is sufficient evidence of carcinogenicity in experimental animals. In some instances, an agent, mixture, or exposure circumstance for which there is inadequate evidence of carcinogen. I knew I was going to suff that up, that word in humans. But limited evidence of carcinogenicity in experimental animals, together with supporting evidence from other relevant data, may be placed in this group. So that's a lot of words. Essentially what it means is if there is limited evidence and that's literally that's the phrase they've used, limited evidence. So if there is limited evidence that it might be carcinogenic to humans and no evidence that it's carcinogenic to animals, it'll get labeled as two B. Or if there is limited evidence that it's carcinogenic to animals and no evidence that it's carcinogenic to humans, it will also be labeled as two B. And that's what's gone on here, because there is a little bit of evidence showing that if you give rats in particular massive doses of this stuff, it might increase their risk of cancer. There's no evidence to show that Aspartame increases cancer risk in humans, but it doesn't need to, to get labeled as two B. As long as we've got one out of two. Right. We've got animals, but we don't have humans, doesn't matter. It still gets labeled as two B, right. Which is very, very different to Aspartame causes cancer. Right. So again, limited evidence in animals, no evidence in humans. We still get a rating of two B possible carcinogen. Right. So that's really important in terms of what we've seen in other areas of the research. There's been two or three massive systematic reviews, or even I think there was a metaanalysis. I'll have to check my notes. But a metaanalysis is kind of like a systematic review that has been recalculated all of these statistics. So they've pooled all of the participant data from each study and then reanalyzed it kind of as like one really big study. So they're fantastic for digging through this sort of stuff. In all of those reports, we do not see any increased risk of cancer in humans. Right. Then I think it was around the same time, maybe a couple of days later, after the IAC released their report about it being a two B carcinogen, the Joint Expert committee on food Additives, or Jekfa for short, for obvious reasons, has come out and said that the upper limit for aspartame consumption, which is 40 milligrams per kilogram, is still perfectly safe. There is no reason for humans to have to worry about that. And in fact, we even see in even the highest consumption of aspartame in normal populations, most people are getting like 10% of that. Right? So we're not even close to consuming what is the upper limit? Sorry, acceptable daily intake, which is even that is incredibly conservative. Right. So based on the studies where they feed these rats, like 20 to 22 cans worth of diet soft drinks yes, we see an increased risk of cancer in those studies. Whether that is relevant to your consumption of aspartame, I don't know. I don't know. Maybe you do drink 22 cans of Coke Zero a day. If you do that, you should probably stop because that's also a buttload of caffeine. But anyway, at normal consumption levels, aspartame appears to be perfectly safe. The last thing I would say on this is, let's say I can't tell you confidently that aspartame doesn't cause cancer, right? I don't know everything. Shocker. What I do know is, right now we don't have any evidence to suggest that it does. But let's say that, fast forward, some evidence eventually builds. Not one study. We see a bunch of studies eventually build and they find it is an increased risk. The fact that we haven't seen it now with these big studies that we've got means that even if there is an effect, it's probably tiny, right? And we'd need to weigh that up against the risk of, say, how does consuming excess added sugar impact your cancer risk? Right? That's not a negligible increase in risk. So potentially swapping to an artificially sweetened soft drink over a regular soft drink is still a win. Right. We also need to look at red meat, alcohol, sun, all of these other things which definitely cause cancer and are definitely more carcinogenic than aspartame. Why are we singling out aspartame and kind of ignoring these other things? So all of that is to say, if you enjoy Coke Zero in moderation, then go for it. I can't see that there will be any increased risk of disease for you in the future. If you enjoy Pepsi Max in moderation, I think there may actually be something wrong with you in terms of your taste buds and maybe just who you are as a person. So I would get that tested. But outside of that, you're probably not going to increase your risk of cancer anyway. If you found this helpful, I would love for you to share it with someone who's going on, banging on about aspartame being a risk, or even just someone who is a bit unsure because they've seen all these scary headlines and they've maybe seen other people online talking about scary stuff. My favorite thing is to explain to people why they don't need to be scared of things, right? Because I think it reduces a lot of the fear and guilt and shame and all of that associated with food, which is probably my jam. That's my favorite thing to do so if you could. So selfishly. If you could help me do that by sharing it with someone or throwing this in your stories, I would be eternally grateful. Otherwise, I'll see you next time for, hopefully, a slightly less echoey podcast. Bye.