Villainy stakes: Sugar turns the tables on artificial sweeteners
Which is worse for you: artificial sweeteners or sugar? The tables have now turned as data show sweeteners are not carcinogenic and added sugar can cause health problems including diabetes and cardiovascular disease. Rather than rely on anecdote or myth, this article looks to inform the debate with the research.
The available evidence points to the fact that there appears to be a correlation between sugar consumption and health problems; none can be detected with artificial sweeteners.
For decades, artificial sweeteners have been attacked as harmful chemicals. One of the oldest artificial sweeteners is saccharin. Starting in the 1980s, the US Congress mandated that any product containing it be accompanied by the following: "Use of this product may be hazardous to your health. This product contains saccharin, which has been determined to cause cancer in laboratory animals."
But what was the basis for this decision? A review article published in The Annals of Oncology in 2004 noted that more than 50 studies had been published looking at saccharin in rats — and 20 were "one-generation studies", they did not look at the rats' offspring.
In only one of those studies did huge amounts of saccharin produce cancer, and it was in a type of rat that is frequently infected with a bladder parasite that would leave it susceptible to saccharin-induced bladder cancer. But "two-generation studies", in which rats were fed lots of saccharin and their offspring were, too, found that bladder cancer was significantly more common in second-generation rats. That prompted many countries to act.
This link has never been confirmed in humans. It turns out that some rats are just more likely to get bladder cancer. Feed them large amounts of vitamin C, and they get bladder cancer.
Studies in humans in Britain, Denmark, Canada and in the US could find no association between saccharin consumption and bladder cancer once they accounted for cigarette smoking (which does cause it). Based on these newer studies, saccharin was removed from the carcinogen list in 2000. But by that time, opinions were set.
Other artificial sweeteners haven't fared any better. Aspartame was introduced in the US around the time that saccharin began taking a beating.
The initial studies showed that aspartame didn't cause cancer in animals, so it was deemed safer than saccharin. But in 1996, a study was published in The Journal of Neuropathology and Experimental Neurology titled "Increasing Brain Tumor Rates: Is There a Link to Aspartame?"
Most people ignored the question mark. Instead, they noted the paper stated that brain cancer had become more common from 1975 to 1992 and more people had started consuming aspartame recently.
There were any number of problems with this logic. Most of the increase in cancer was in people 70 years and older, who were not the main consumers of aspartame. And because aspartame was approved in 1981, blaming it for a rise in tumours in the 1970s seems impossible.
Finally, more comprehensive studies couldn't find links. These included a case-control study from The Journal of the National Cancer Institute of children and a cohort study of more than 450,000 adults in Cancer Epidemiology Biomarkers and Prevention.
Some people still point to later rat studies with aspartame as concerning, but these are contested. More important, as we've seen from saccharin, there are also big differences between rats and humans.
A 1998 controlled trial could detect no neuropsychological or behavioural effects caused by aspartame. Even a dose at 10 times the normal consumption had no effect on children with attention deficit disorder.
A safety review from 2007, published in Critical Reviews in Toxicology, found that aspartame had been studied extensively and that the evidence showed that it was safe.
It is true that people with phenylketonuria, a rare genetic disorder, need to limit their consumption of aspartame, since phenylalanine is one of its components. But for most people, aspartame isn't a concern, even outside of cancer.
It's also true that some of the sugar alcohol sweeteners, such as sorbitol or mannitol, can have a laxative effect or cause bloating when eaten in large amounts by some people. In normal use by most people, though, all of the approved artificial sweeteners are safe.
But what about sugar?
The conversations are seldom about naturally-occurring sugars or carbohydrates you find in things such as fruit, they are about added sugars — which are the problem.
The US Centers for Disease Control and Prevention reports that US children are consuming between 282 calories (for girls) and 362 calories (for boys) of added sugars per day on average. This means that more than 15% of their dietary caloric intake is from added sugars. Adults are doing slightly better, but not by much.
This consumption isn't distributed equally, however. For instance, about half of people consume no sweetened drinks at all. The next 25% consume about 200 calories per day from sugar drinks. The top 5% of people, though, consume more than 560 calories a day, or more than four cans of soda.
Epidemiological studies have found that even after controlling for other factors, a population's intake of added sugars is associated with the development of type 2 diabetes, with a 1.1% increase in prevalence for each can of sugar-sweetened soda consumed on average per day.
A study following people for an average of more than 14 years published last year in JAMA Internal Medicine found those in the highest quintile of added sugar consumption had more than twice the risk of dying from cardiovascular disease than those in the lowest quintile, even after controlling for many other factors.
The accompanying editorial noted that the increased risk of death began once a person consumed the equivalent of one can of Mountain Dew in a 2,000-calorie diet, and reached more than a fourfold increase if people consumed more than one-third of their diet in added sugars.
It should come as no surprise that the intake of added sugars is significantly associated with body weight.
A systematic review and meta-analysis of randomised controlled trials, published in BMJ 2012, found that sugar intake increased both fat and overall weight.
Another meta-analysis of randomised controlled trials, published in The American Journal of Clinical Nutrition in 2013, found that sugar-sweetened beverages alone cause body weight to go up in adults. In comparison, a meta-analysis of randomised controlled trials of artificial or low-calorie sweeteners published last year in the same journal found that their use led to lower body weight and less overall fat.
There is a potential, and probably real, harm from consuming added sugars; there are most likely none from artificial sweeteners.
Source: New York Times