Is aspartame carcinogenic?

The International Agency for Research on Cancer (IARC) and the World Health Organization announced recently classified the artificial sweetener aspartame as a possible carcinogen in a Group 2B classification, meaning that the evidence is “limited.”

The classification indicates the level of CERTAINTY that a substance can cause cancer, meaning there is insufficient evidence to prove causality. The evidence is limited in the case of aspartame causing cancer in humans with what we know today.

While most headlines will have you fear this “new” stance, it is not new. “JECFA concluded that the data evaluated indicated no sufficient reason to change the previously established acceptable daily intake (ADI) of 0–40 mg/kg body weight for aspartame. The committee therefore reaffirmed that it is safe for a person to consume within this limit per day”. They maintain that aspartame consumption of up to 40 mg per kg of body weight per day (the equivalent of 9 to 14 diet soft drinks) is safe.

• Past animal studies found evidence of chronic toxicity, but human studies did not produce the same data.
• Sugar substitutes are known as high-intensity sweeteners because they’re often hundreds, if not thousands of times sweeter than table sugar.
  • Synthetic: sucralose, aspartame, and saccharin
  • Natural (from plants): allulose, stevia and monk fruit extract
• Sweeteners of many types are in packaged foods such as bread, cereals, juices, fruit cups, yogurt, salad dressings, gelatin, medicines, ice cream, toothpaste, chewable vitamins, condiments, chewing gum, protein powders, and snacks — the number of these products has surged in the past 5 years.

Digging deeper – is there a downside?

We have known for some time that studies suggest that ‘fake’ sugars can also have unexpected effects on your gut and metabolic health and even promote food cravings and insulin resistance, a precursor to Type 2 diabetes. However, as you can see, the research can be debated and confusing, even to the authorities conducting and interpreting the research.

Gastrointestinal Symptoms

Artificial sweeteners may cause unpleasant GI symptoms and trigger migraines in some people. Some studies suggest that “artificial sweeteners may induce pro-inflammatory changes in gut bacteria and gut wall immune reactivity, which could negatively affect individuals with or susceptible to chronic inflammatory conditions.” If you have underlying GI problems, these may exaggerate the problem.

One rigorous study by the Weizmann Institute of Science looked at what happened when people were given aspartame, saccharin, stevia, or sucralose in amounts well below the FDA’s daily allowances. The study found that these sweeteners caused changes in both the function and composition of the participants’ gut microbiomes, the communities of bacteria, viruses and fungi that live in the intestines.

Why this matters: The microbes in your gut play many important roles: They transform the food you eat into enzymes, hormones and vitamins. We need them.

Taste Receptors

Some studies suggest that sugar cravings could intensify and people could eat more sugar and sweetened foods as a result. These sweeteners and their level of sweetness may affect how your brain perceives sweetness. The latest sweetener, neotame (the next generation of aspartame), is 13,000 times sweeter than sucrose (table sugar). It begs the question, are we making everything taste sweeter? Taste buds can change for various reasons such as illness and malnutrition. Could we alter the taste of our preferences for sweeter foods?

“Americans consume 22.3 teaspoons of added caloric sweeteners a day. Sweeteners range from 180 to 13,000 times sweeter than sugar. In summer 2014, 20 people from Kaiser Permanente California facilities cut out all added sugars and artificial sweeteners for 2 weeks: 95% of participants found that sweet foods and drinks tasted sweeter or too sweet, 75% found that other foods tasted sweeter, and 95% said moving forward they would use less or even no sugar. Additionally, 86.6% of participants stopped craving sugar after 6 days.”

Weight Control

The Dietitian Says….

The research is ongoing. More research is needed to prove direct causality. If these foods are something you enjoy, don’t fear they will cause you cancer. Sweeteners may have their place in a well-balanced approach to a healthy lifestyle when eaten in moderation. However, be aware of how much is in your diet. If you are trying to lose weight and you constantly choose “low sugar,” “sugar-free,” “no sugar,” and “unsweetened,” on the call-out label, these add up. When people are desperate to lose weight, an abundance of sweeteners can be used in order to displace calories.

Sugar has been demonized when it comes to children. Parents may be looking for ways to reduce sugar in their diet, but sweeteners are not recommended for children. Practicing moderation with sweets and providing nutritious foods in every meal is a better approach.

I am also cautious when I counsel clients that cater to the body’s craving for sweets and fill that void with sweeteners. It may only increase their appetite for them. While anecdotal, many clients who consistently use sweeteners to reduce calories complain of gas and bloating and rarely feel satisfied with these foods.

What has worked for the me and the many clients I counsel is having a more whole food approach, focusing on mixed meals several times per day. These meals should include a protein, carbohydrate, dietary fat, and a variety of fruits, vegetables, herbs and spices.

Top 5 Ways to Decrease Your Consumption

1. Read labels, specifically the ingredients with erythritol, allulose and sucralose, stevia, monk fruit, etc. in foods such as yogurts, beverages, puddings, and other foods. You can lower any potential risks by not heavily using any one artificial sweetener.
2. Use sweeteners in moderation.
3. Reduce your consumption of processed foods and cook foods at home.
4. Have a little of what you really want rather than try to find so many ways to turn that craving. Sugar in moderation is not unhealthy. One teaspoon of sugar has 16 calories, so one or two teaspoons in your tea or coffee is unlikely to cause any health problems. Case in point, even people with diabetes can use sugar if they budget it into their dietary pattern for the day.
5. Focus on a healthy plate or snack with a mix of protein, fruits, vegetables, whole grains, and some dietary fats.

UPDATE 8/14/23

Findings published in the International Journal of Obesity show an association between long-term intake of artificially sweetened beverages containing aspartame and saccharin and risk of higher body mass index, weight and waist circumference. The study involved 3,088 young adults followed over 25 years who regularly drank artificially sweetened or diet drinks, and researchers encouraged people to find “alternatives to artificial sweeteners in foods and beverages, especially since these added sweeteners may have negative health consequences.” – Health Daily News

Sources:

Javier Cotelo, MD. August 2023. Medscape Medical News. Artificial Sweeteners Increase Cardiovascular Risk.

Science Direct: Satiety.