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Are artificial sweeteners bad for you?

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The promise of a calorie-free sweet treat seems too good to be true – but is it?

Since a chemist accidentally discovered saccharin in 1887, artificial sweeteners have been controversial. Debates about their safety, their effectiveness for weight loss, and their flavor have been going on for more than a century.

Recently, the World Health Organization (WHO) updated its guidelines on artificial sweeteners. To help us navigate through the research in search of answers, we turned to sports dietitian Angie Asche.

The main takeaways:

  • The WHO labeled aspartame a “potential” carcinogen but the evidence was “not convincing”.

  • Some studies have found artificial sweeteners are associated with weight gain.

  • A diet lacking in whole foods, fruits and vegetables is more concerning than the occasional artificially sweetened drink or snack.

  • Reducing your overall consumption of added sweeteners – sugar and artificial – is the best strategy for long-term health and weight management.

Does aspartame cause cancer?

When the WHO speaks up, people take notice. So when they labeled widely-used artificial sweetener aspartame a "possible carcinogen“ people were, understandably, freaked out – even though they also said the evidence was “limited, but not convincing”.

So what does that mean for your love of diet soda?

“The bulk of the evidence is currently from rodent studies,” Angie says. “We need more evidence in humans specifically because right now all we have is associations, not a cause-effect relationship.”

Angie adds that we also have limited evidence on how exactly aspartame would be able to cause cancer.

Of course, that hasn’t stopped people (both professionals and less reputable sources) from floating theories like potential impacts on brain chemicals and DNA damage.

But again, these are just theories. While the WHO is advising against the regular intake of artificial sweeteners, they haven’t made a definitive call on the cancer-causing impact of aspartame.

Do artificial sweeteners cause weight gain?

Many people who consume artificial sweeteners do so to combat weight gain. Since weight loss can only happen when you consume fewer calories than you burn, a low-calorie snack or drink should help, right?

Not so, according to the WHO, who now advise against the use of artificial sweeteners for people trying to control body weight – though they make an exception for people with diabetes who need to manage their blood sugar levels.

One 25-year study actually found that intake of artificial sweeteners was associated with higher BMI and body weight and larger waist circumference.

“This also isn’t the first time we’re seeing these kinds of results,” Angie says. “In 2008, an observational study reported that participants who consumed artificial sweeteners were more likely to gain weight over time than those who did not.”

But she also stresses that this is “an incredibly complicated topic”.

“You could find one study that shows a very different conclusion from the next,” Angie says, noting that observational studies like this one can’t establish a cause-and-effect relationship.

Should you stop consuming artificial sweeteners?

Angie says that by fixating on artificial sweeteners, people could miss the nutritional forest for the trees.

“The majority of Americans are under consuming the recommended amount of fruits and vegetables per day, while ultra-processed foods make up nearly 60 percent of what the typical adult eats, and 70 percent of what kids eat,” Angie says.

“The reason I’m not personally a fan of artificial sweeteners is that when you look at the types of foods these are being added to, they’re often ultra-processed and lack nutrient density,” she says.

“Unlike consuming whole foods that provide fiber and protein, these are not going to fill you up in the same way. Plus there are still a lot of unanswered questions regarding their effects on appetite, our gut microbiome and body composition.”

How to cut back on the sweet stuff

When it comes to both artificial sweeteners and added sugars, Angie says, less is best.

So how can you cut back?

  1. Become food label literate. “Sugar is often added to things we don’t even realize, like pasta sauces, ketchup and dressings,” Angie says. “If you’re not interested in making your own, there’s a good chance you can find a store-bought version with lower sugar that uses natural sources such as fruit to sweeten.” The key is to identify the total sugars vs added sugars – if the amount of total sugars is higher than the added sugars, it means most of the sugars found in that product have come from natural sources like dairy, fruit or vegetables.
  2. Make tiny drink tweaks. If you find it hard to make the switch from super sweet beverage to plain water, take it slow. “Try half the syrup added or skip the whipped cream on top of your coffee,” Angie says. “Even just cutting back from 3 sugars to 2, or 2 to 1, is a good step.”
  3. Use fruit as a replacement. “When baking, you could use bananas or applesauce instead of refined sugar, which help add more micronutrients to the dish along with sweetness,” Angie says. “Or choose a lower sugar yogurt, but add fresh berries.”
  4. Track your sugar. If you’re curious about your consumption, spending a few days tracking your food intake can help you get a sense of your baseline. “It can be incredibly difficult to know just how much sugar is in foods or beverages on your own, and it can be pretty eye-opening.” The American Heart Foundation recommends 35 grams or less of added sugar per day for men, and 25 grams or less per day for women.

Disclaimer: This Centr content is adapted with permission from an article written by The content herein represents Centr’s interpretation of the original source material.

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