Artificial Sweeteners: The Myths, Facts, and practical implications

There are strong claims surrounding artificial sweeteners without evidence to back them up. What does the research show?

What are artificial sweeteners?

Artificial sweeteners are sugar substitutes that provide a sweet taste but don’t have any calories. Sugar, for example, has 4 calories per gram. Some common artificial sweeteners include aspartame, stevia, and sucralose.

Artificially sweetened foods and drinks are a popular choice for those wanting to consume less calories but still have a sweet tooth and want to enjoy something like a soda or ice cream.

A diet coke, for example, tastes sweet but doesn’t have any sugar or calories in it because of the use of aspartame.

Common claims of artificial sweeteners

After a quick google search, “side effects of artificial sweeteners”, here is what came up:

• Headaches

• Dizziness

• GI problems (bloating, digestive issues, diarrhea)

• Obesity

• Diabetes

• Stroke

• Cancer

• Death

That is a serious list that shouldn’t be taken lightly, but misleading claims are even more serious. There are already have far too many baseless claims in the nutrition field.

For example, an article called “Artificial Sweeteners and Toxic Side Effects” supports these claims, but mostly by using correlational data or mechanistic data. Human control trials should always be held with the most weight, and those studies have been done. Also, the author of the article (who is a doctor) misuses the word “toxic” in their title, which is a red flag.

Also one of the articles on a website that came up upon this search was titled “5 Terrible Side Effects of Artificial Sweeteners”. This article had ZERO references or sources listed.

Does aspartame cause long term health problems?

I am choosing aspartame here because of how common it is, being the sweetening ingredient in most diet sodas. Aspartame is a class 2B carcinogen, according to the WHO (World Health Organization). This information is a common defense behind the “aspartame causes cancer” claim.

Group 2B carcinogens are defined as, “Possibly carcinogenic to humas. Limited evidence in humans. Less than sufficient evidence in experimental animals”

The WHO, along with the Joint Expert Committe on Food Additives (JECFA), state,

“The assessments of aspartame have indicated that, while safety is not a major concern at the doses which are commonly used, potential effects have been described that need to be investigated by more and better studies.”

They describe the acceptable daily intake of aspartame as 0-40mg/kg of body weight per day. For an 80kg person (176 pounds), you would need to have at least 13 diet sodas per day to be outside of this safety limit.

Basically, they are acknowledging the importance of common claims and correlational data, even though more carefully controlled studies do not show any safety concerns. The evidence that aspartame causes cancer and other health problems is extremely weak and even if there are health consequences, the amount that one would need to consume to be at an unsafe level is very large.

Artificial sweeteners and weight loss

Associations between artificial sweeteners and obesity have been made. This correlational data has led to the bold claim, “artificial sweeteners make you fat.”

I believe this correlation is due to the healthy user bias, meaning that health-conscious people are less likely to consume artificial sweeteners.

Also, someone who is overweight or obese might choose to consume artificial sweeteners as a result of their weight gain, in an attempt to reduce overall calorie consumption, skewing the data even further.

Correlational data is important, but we should examine the human controlled trials before making any strong conclusions.

This study examined the effects of a weight loss program that either used water or artificially sweetened beverages. The results are extremely strong because of how this study was conducted. Also, the study uses the term “non-nutritive sweetener” instead of “artificial sweetener”, but these terms are interchangeable.

Here is what makes this a good study:

• 303 total participants, ~150 per group

• Participants were overweight or obese and weight stable for the 6 months leading into the study.

• The long study duration. The study intervention lasted an entire year, and they followed up with the participants going through a 40-week maintenance phase.

• Both groups received a comprehensive weight loss program involving weekly 60-minute educational classes related to weight loss.

• Groups were instructed to have at least 24 ounces of water or artificially sweetened beverages (depending on their group assignment)

The group consuming non-nutritive sweeteners actually outperformed the water group by a large margin, losing 8% of their body weight compared to 3%.

Also, the non-nutritive sweetener group outperformed the water group during the 40-week maintenance phase. You can see the results in the graph below.

Cardiometabolic biomarkers, hunger levels, and physical activity levels were measured before and after the intervention. You can find the table of results by clicking this link to the study.

The authors state,

“It is not possible from the present data to explain why the NNS group lost more weight than the water group despite receiving identical weight loss instruction and beverage interventions that both contained zero calories.”

I speculate that the weight loss success of the non-nutritive sweetener group is likely due to increased diet enjoyment, rather than something “magical” about artificial sweeteners.

One of the participant selection criteria was that they had to already be regularly consuming artificially sweetened drinks at least 3 times per week. It is likely that when the water group had a craving for one of these drinks, they had to turn to regular soda or another sweet treat (which has calories, unlike the diet sodas).

Summary

I am aware that I did not address every claim and every artificial sweetener, but I hope this highlighted that artificial sweeteners are likely safe to consume. The evidence that suggests otherwise is weak or non-existent.

If there is one takeaway from this article, let it be this: if you like artificial sweeteners, you should have them. If you have a sweet tooth, straying from all sweet things sounds like a plan that will make you unhappy and probably won’t work anyway.

I wouldn’t call artificial sweeteners healthy, but I certainly wouldn’t call them unhealthy either. If you have too much sugar (or too many calories in general), then consuming artificial sweeteners might be a great tool for you to make positive change.

What’s next? How much water should you drink?