Cardiologist says sugar and carbs are the main cause of rising obesity rates

Sugar and carbohydrates are the main culprits in rising obesity rates, and exercise doesn’t actually help you lose much weight. That’s according to a provocative article in a leading medical journal by three health experts. British cardiologist Dr Aseem Malhotra is one of the co-authors and he spoke to Lateline’s Emma Alberici.

EMMA ALBERICI, PRESENTER: For those of you who said this will be the year you’d start exercising to lose weight: “don’t bother.” That’s the word from the UK, where three of the world’s leading health experts say it’s bad diet, not a lack of physical activity, that’s making us obese.

They’ve written a provocative article in a leading British journal pointing out that over the past 30 years, as obesity has rocketed, there’s been little change in exercise habits around the Western world.

The authors say excess sugar and carbohydrates are behind a surge in preventable diseases. They argue it’s not the number but the source of the calories that matters most, because sugar promotes fat storage and hunger.

Processed foods are causing more sickness than smoking, alcohol and physical inactivity combined.

These views aren’t shared by all public health experts. This is what the director of research for the CSIRO, Professor Manny Noakes, thinks:

MANNY NOAKES, PROF., NUTRITION AND HEALTH, CSIRO: Look, it’s a complete myth to think that just one thing – like sugar or carbohydrate – is going to be or has been the cause of the obesity problem. If we look at what people do eat, 35 per cent of their total calorie intake comes from junk foods and alcohol. Some of those are high-end sugar and carbohydrate. Some are high in fat and salt. So it’s a complete myth to consider that it’s just one thing.

EMMA ALBERICI: The Australian Food and Grocery Council, which represents the packaged food industry, rejects the idea that sugar is the biggest evil.

GEOFFREY ANNISON, DEPUTY CEO, AFGC: Well, we don’t believe it does have a major role. One of the problems of focussing on a single nutrient and demonising it: it moves the message away from that of variety, of moderation and balance as a key to maintaining a healthy weight, along with physical exercise, of course.

EMMA ALBERICI: But for years many public health experts have been calling for a ban on junk food companies sponsoring major sporting events and they want an end to advertising of high-sugar foods and drinks that target children.

British cardiologist Dr Aseem Malhotra is one of the co-authors of that article in the British Journal of Sports Medicine. He joins me now from our London studio.

Dr Malhotra, thanks for joining us.


EMMA ALBERICI: Are you suggesting that exercise can play no role at all in fighting obesity?

ASEEM MALHOTRA: Well, I think the most important message from this is: is exercise has many health benefits – no one could deny that – in reducing the risk of heart disease, high blood pressure, type 2 diabetes, even many cancers.

But it’s quite clear from the evidence: when it comes to weight loss, the impact of exercise is really quite minimal. And therefore, when it comes to obesity, it’s quite clear that the obesity epidemic has been driven by the type and the amount of calories we’re consuming.

And I think we have to actually go a bit beyond the conventional wisdom about, you know, energy balance, calories in versus calories out and actually concentrate on the quality of those calories. Obesity is more of a disease of fat storage, rather than about excess calories.

So the main message is, actually: exercise is very good for your health. Of course you should do it. If I didn’t believe that, I wouldn’t spend 20 to 30 minutes exercising daily myself. But I’m very much aware that I’m doing it for my health benefits, even though I’m normal weight. You know, I used to be somebody that used to consume lots of sugar and carbohydrates, realised it was having an adverse effect on my health, in particular, you know, having fat storage around the waist: I know that’s a risk as a cardiologist.

I see lots of patients. I’ve treated thousands of people in my career and a lot of people who have come in with heart attacks aren’t overweight but they have what we call the metabolic syndrome. And that’s really important because, actually, when you look at diet-related disease, about up to 40 per cent of people with a normal body mass index will harbour the same metabolic abnormalities as people with obesity, such as high blood pressure, type 2 diabetes, cardiovascular disease, for example.

And in context: you said in your intro, you’re absolutely right. Poor diet, according to the Lancet global burden of disease reports, contributes to more disease now than physical inactivity, smoking and alcohol combined. So we’re talking about health, which includes exercise – and the right diet for all ages and all sizes.

EMMA ALBERICI: So what does constitute a bad diet?

ASEEM MALHOTRA: Well, I think: let’s look at it in terms of what we put in our mouths, what we eat has an effect on all aspects of our body. In fact, one of the interesting things that even I’ve learned in the last few years is actually most of our calorie burning happens from even doing nothing: just from basic bodily functions, metabolism of the body. About 60 to 75 per cent of burning of calories happens from that.

Exercise adds a bit more, there’s no doubt about it. But actually, what happens, is when people exercise, exercise itself can sometimes be quite a powerful appetite stimulant.

So, to answer your question specifically, what I would say is: let’s think about what we’re eating and how it affects our body. Let’s remove the foods for example, the types of foods that have no impact or have little nutritional value. So it’s very clear that added sugar has absolutely no nutritional value whatsoever and, contrary to what the food industry want you to believe, the body doesn’t require any carbohydrate for energy from added sugar. So that’s something we can do without.

And we know the food industry have been spiking our food with added sugars. We also know that carbohydrates and particularly refined carbohydrates – so carbohydrates that lack fibre, sugar being one of them – have the biggest impact on insulin in terms of surges of insulin in our body. And insulin is a fat storing hormone.

So we have to think in a much more nuanced way about our health. And to be honest, the food industry: you know, they’re there to sell food. They’re there to make a profit. They have no interest in your health. That’s a legal responsibility.

So they’ve manipulated things and bent the rules in a way where they’ve associated junk food and sport, which I think, really, is quite shameful. We have to end that association. This is having a negative impact on our children. The perceptions is that you can basically have a sugary drink or, you know, junk food, a burger and chips: as long as you exercise, that’s fine. Well, actually, that’s misleading and unscientific.

EMMA ALBERICI: Isn’t it a little alarmist to be comparing the food industry to big tobacco, as you’ve done?

ASEEM MALHOTRA: It’s not alarmist, Emma; it’s the actual truth. Kelly Brownell, a professor at Yale, said – public health professor at Yale, very distinguished professor – said that he can think of nothing the food industry is doing that the tobacco industry didn’t do.

And you’ve got to remember: it took 50 years from when the first links between smoking and lung cancer were raised, published in the British Medical Journal, before any effective regulation happened. And that’s because big tobacco adopted what I call a “corporate playbook” of denial that their cigarettes were harmful, planting doubt, buying the loyalty of scientists and confusing the public.

And that level of denialism, just to put in perspective: in 1994, the CEOs of every major tobacco company went in front of US Congress and swore under oath they did not believe nicotine was addictive or smoking caused lung cancer. Let’s remember. Let’s learn from history and not let the same mistakes happen with the food industry in sugar. And I’m very concerned about that.

EMMA ALBERICI: Is regulation what you’re after?

ASEEM MALHOTRA: Well, I think we have to regulate because, ultimately, when we think about the way that… the root cause of the obesity epidemic is actually rooted in the food environment. So that means that, actually, our food choices are very much determined by our environment. And we have an oversupply of junk food, of cheap sugary food and the only way we’re going to combat this is by dealing with that food environment.

And that’s basically looking at what we call the three As in population or public health: the availability, the affordability and the acceptability of these foods. So things like sugary drinks tax: we know in the UK, for example, a tax on sugary drinks by about 20 per cent; we know that would prevent around 180,000 people from becoming obese. And that’s been a study that’s been done by Oxford researchers.

And we have to look at the advertising of junk food. You know, banning junk food advertising, I think, is very important. The food industry put billions of dollars, billions of pounds into junk food advertising because they know it’s going to increase consumption. And unfortunately the most vulnerable members of society, especially children, are victims of this.

EMMA ALBERICI: It’s not just food and drink companies spreading what you say is essentially a myth. They’re in many cases backed by quite respectable scientists. In this country, one of our most prestigious universities continues to argue that sugar is harmless when it comes to obesity and type 2 diabetes?

ASEEM MALHOTRA: Well, I find that quite concerning. I think the thing to say is: I’m not into practising eminence-based medicine. It’s independent evidence-based. I don’t know which university it is and I don’t know what they’re basing their research on or whether there’s any issues around funding related to the food industry: that’s something maybe, you know, people need to look into.

But certainly from what I’ve looked at, it’s very clear that if we’re going to actually improve the food environment, if we’re going to improve what people are consuming, let’s just stick to the basic science. I don’t think anyone can disagree – anyone, everyone in that university – that there is no biological requirement for added sugar. You know, the truth, the mantra is very true. You know, food can be the most powerful form of medicine or the slowest form of poison. And actually the randomised controlled data, trial data support that.

So, for example, adopting a Mediterranean diet after a heart attack, one that’s high in fat, a high-fat Mediterranean diet is almost three times as powerful at reducing the risk of death than taking a cholesterol-lowing statin pill. So, you know, people need to know that that’s the information that’s being sequestered, that’s being held back.

And actually, there’s a huge area that isn’t being explored enough which is actually: the impact of lifestyle can be very powerful on your health, even people who are overweight.

I mean, one of the studies published in the New England Journal of Medicine a couple of years ago – again, a randomised control study – showed that people who are high risk of heart disease who adopted a Mediterranean diet significantly reduced their risk of stroke, heart attack or death within a short space of time. And actually, those effects were independent of body weight. So even people who were obese: even if they didn’t lose weight, the risk of adverse health outcomes was reduced significantly.

So really, the truth is: let’s all think about a little bit more about what we’re eating, you know, concentrate on good nutrition, try and reduce foods that don’t add any value to your diet. You can still enjoy your food. Do some exercise and actually, within a space of a very short space of time, Emma, a lot of people will have a dramatic improvement in their health.

EMMA ALBERICI: Dr Malhotra, I thank you very much for giving us the time you’ve given us tonight.