The Diet Food That Could Be Making You Fat
Artificial sweeteners abound. Yet they have weird aftertastes, dubious effects on blood sugar and growing evidence shows that they may make you gain weight. WH breaks down the shaky future of substitutes – and what they could be doing to your waistline (a
Going sugar-free to lose weight? You need to know this...
With sugar on everyone’s “don’t” list (it’s now accused of causing not only weight gain, but possibly diabetes, cancer and heart disease) artificial sweetener use is soaring. We’re scarfing the stuff like never before: consumption of sugar substitutes surged by 54 percent between 1999 and 2012 (going up a startling 200 percent in kids) and demand is predicted to rise another five percent by 2020. Scientists are tinkering with new plant-based varieties that aim to be healthier and better-tasting than previous labcreated sweeteners and several are already on the market. All-natural and nearly zero kilojoules: what could possibly go wrong?
Experts are increasingly unsure of how to answer that question – or exactly what advice to give to their clients. “There’s a lot of confusion about sugar substitutes these days,” says nutritionist Ashley Koff. Despite the health halo crowning the new sweeteners – they come from leaves or fruit or some form of plant – a few things worry researchers: could they, like earlier sugar replacements, possibly make people gain weight? Is something still “natural” if it has been chemically altered and manipulated? Here’s what we know so far.
Alongside doo-wop and hula hoops, artificial sweeteners came of age in the 50s, promising weight loss through kilojoule reduction. They were also thought to be better for people with high blood-glucose levels, like diabetics or those with insulin resistance, because they helped them take in less sugar. Then, around the early 2000s, research began to suggest that sweeteners might promote weight gain and experts were mystified. Some assumed a psychological link – that if you know you’re saving kilojoules on your diet drink, you might subconsciously up your food intake. But more recently, as researchers delved deeper into the physiological mechanisms underlying the sweetener-weightgain connection, another shocker emerged: substitutes may actually increase your risk for high blood sugar, metabolic syndrome and
diabetes – the very things they were supposed to prevent. A 2014 study in the journal Nature found that after people added artificially sweetened foods to their diets for just one week, their overall blood-sugar levels rose. “This suggests insulin resistance, which is a step toward pre-diabetes,” says physician nutrition specialist Dr Melina Jampolis. “Insulin resistance makes it harder to lose weight because insulin promotes fat formation and prevents the breakdown of fat, so it’s more difficult to burn it off.” The result? Stubborn kilos plus a higher risk for diabetes. Substitutes may also affect the digestion of other foods we eat, says Dr Eric Walters, a chemist who has studied sweet and bitter tastes. “There are sweet taste receptors throughout the intestines that pump out glucose transporters to help you absorb any sugars. So if you consume a diet drink along with starchy fried chips, which quickly break down into glucose, there are already extra transporters around. That moves the glucose into your bloodstream faster than usual.” That’s scientific speak for: here comes a blood-sugar spike! And crash! Which impacts hunger, mood and cravings and leads to more snacking. But sugar subs don’t stop there, oh no. They also might mess with your microbiome, according to a 2014 study in mice showing changes in gut bacteria that affected blood-sugar regulation. And research late last year in the US found that as aspartame – one of the most ubiquitous sweeteners, on the market since the early 1980s – breaks down in the gastrointestinal tract, it produces a chemical that interferes with a digestive enzyme that may help prevent obesity, diabetes and metabolic syndrome. “We used to think of these sweeteners as metabolically inert, that they passed through your body without any measurable impact. But evidence is showing that may not be the whole story,” says Jampolis.
The continual drip-drip of negative studies has made the search for better low-kilojoule sweeteners, without the problems of their predecessors, even more pressing. But so far, the evidence on the new batch is mixed. Until the 1990s, all artificial sweeteners had been created in the lab – this includes familiar names like saccharin, cyclamate and aspartame (see the timeline on the next page). But within the past 20 years, two sweeteners, sucralose and stevia, changed the game by using a natural substance as a starting point. Sucralose begins as table sugar, then scientists tinker with its atomic structure; stevia is a purified extract made from leaves of the stevia plant. Natural is now the word every sugar substitute wants to have on its label (and in its PR portfolio) – but the definition of that isn’t as simple as it seems. Allulose, which, in 2014, was given GRAS status – that stands for “Generally Recognized As Safe” by the FDA – is found in jackfruit, figs, raisins and other fruits. It has the same molecular formula as glucose and fructose, but the quantities in the fruit itself are so minuscule that to make enough of it, the actual product must be assembled on a molecular level in the lab. The company calls the process “enzymatic conversion of fructose to allulose.” Extracts from the Southeast Asian monk fruit were approved as GRAS in 2010 and are now infused in products like ice cream, beverages, yoghurt and sauces. Monk fruit extract too has been manipulated to produce a concentrate that is 150 to 200 times sweeter than table sugar – which is the reason it (and other subs) can be used in tiny amounts with a near-zero kilojoule load. (Some experts feel this flavour intensity may retrain our tastes, keeping us craving yet more sweetness.) Monk fruit is also way more expensive than sugar and is often combined with other less costly sweeteners, like stevia.
FASTER TO MARKET
Are these isolated, extracted substances truly “natural,” as their marketing suggests? Some people argue with that description – since the substances are manipulated in a lab – but nonetheless, these products have had a huge advantage in the approval process. That’s because the FDA’s GRAS system assumes safety in substances made from something that’s already in the food supply and stevia leaves, for example, have been used in traditional medicines by indigenous populations in Brazil and Paraguay for generations. So while it took 16 years of research and evidence of safety for aspartame to pass FDA review, the newer sweeteners have moved along a much shorter path in the GRAS process. For instance, the “development programme” to get stevia approved took six years, according to Dr Grant DuBois, a chemist who worked on the purified form of stevia. This bothers many researchers. “I don’t think we have enough data so far to say that monk fruit or stevia are less concerning than other sweeteners,” says Dr Zhaoping Li, chief of the division of clinical nutrition at UCLA in the US. “Anytime you have a single compound, consumed regularly and in large quantities, it generates concern over the long-term health risks.” And what about weight loss? So far the data suggests that the newer, “natural” substitutes have the same counter-intuitive effects as the earlier artificial sweeteners. In new research from Singapore, scientists asked volunteers to down either sugary drinks or diet ones made with aspartame, stevia or monk fruit. The people who had the drinks with substitutes – no matter the source – ate more later and “made up for” the kilojoules they had skipped. The problem, says Koff, is “whether a low-kilojoule sweetener has an artificial or a natural source, what you’re doing is trying to fool your body.” But the body knows.
So what’s a conscientious healthy eater to do... Besides just give up and become an unconscientious, unhealthy eater? One avenue, says Koff, is to look hard at your sweet cravings. “Substitutes keep us hooked on sweet tastes,” she says. “Some of the artificial sweeteners are tens of thousands of times as sweet as sugar. Someone who consumes them often is going to eat an apple and no longer think it tastes sweet at all,” says Koff. Researchers already know that the “sweet tooth,” while innate, can also be culturally influenced. Evidence: 330ml of Coke has 35g of sugar in South Africa, versus 32g in the version sold in Thailand. We really can retrain our taste buds by cutting down on all sugars, real and artificial. Not that it’s an easy task. Packaged foods contain some form of sweetener – and while many of these sweeteners have been made in the lab, products aren’t required to tout that on their labels. So when you eat a “naturally” sweetened yoghurt or a wholewheat English muffin, you may unknowingly be ingesting sugar substitutes. “The front of the product packaging is purely designed for marketing reasons. The consumer reads words like gluten-free, whole grain, natural, sugar-free, lowcarb on the front and can easily fall into the trap of thinking that it’s a healthy product and buy it immediately,” explains integrative clinical nutritionist Lara de Chazal. “The key to mastering your own health is to become an ingredient and label expert and to turn the package over and scrutinise the ingredient listing and nutritional values to be sure that all the ingredients and nutritional values are aligned with your particular health goals,” says De Chazal. And even then, the subs can hide in plain sight in the “Nutritional Facts.” (Did you know that rebiana is stevia extract? Now you do.) Who can (or wants to, for that matter) memorise the entire list of generic names for lab-enhanced sweeteners? Dietician at Lila Bruk and Associates, Samantha Burns also explains how South African food manufacturers have used marketing strategies to bamboozle buyers, “In the past they used to label sweets ‘fat free’ on the front of the package, implying that the product is “healthier”, when in fact, yes, it is fat free, but let’s not mention the huge amounts of sugar you will be consuming,” says Burns. However, after new South African food labelling and advertising regulations (R146) were passed in March 2010, all labels and advertising of food products in South Africa have been revised and strict rules have been put into place. Labels on packaging now must only be factual, not confusing to the consumer,” says Burns. This is great, but unfortunately sugar subs still pose a big problem. “Artificial sweeteners are not required by law to be listed on the front of packaging, only in the ingredient list. This means that consumers are not always aware of them. To make things worse, food and beverage companies are relying heavily on artificial sweeteners as a result of sugar taxation, making it more difficult for consumers to keep up to date with ingredients,” says Burns. That’s why some nutritionists say it may be best to choose real sugar (try Natura unbleached, non-GM, non-radiated sugar) over substitutes. Remember to limit your intake to six teaspoons of added sugar per day (the World Health Organization’s recommendation). Other lessprocessed sources include raw honey and maple syrup – the real stuff, not maple-flavoured syrup! “You’ll get vitamins, minerals and plant nutrients, along with the satisfaction of carbs and kilojoules,” says Koff. And there’s one other uber-simple fix: “Buy less food that comes in a box,” says nutritionist Jackie Newgent. After all, melons and strawberries are deliciously sweet – and don’t even require a nutritional-facts label.