By Misagh Karimi, M.D. at City of Hope Newport Beach
If you drink diet soda to save calories, chew sugar-free gum to protect your teeth, or start your mornings with a non-fat yogurt, you may be wondering if you need to change your habits in light of new findings about aspartame — the artificial sweetener used in all of these products and many others.
This week, the World Health Organization (WHO) categorized aspartame as “possibly carcinogenic” to humans. The internet is filled with wild claims that anything artificial is bad for you and that diet sodas are basically toxic. On the other hand, aspartame has long been one of the most-used — and most-studied — sweeteners in the world and has been FDA-approved for decades.
All of this news can be a bit overwhelming and confusing. So, what do these new findings mean for you?
The short answer for most adults is this: you don’t need to worry about having a diet soft drink every now and then. But cutting back on sugar and artificial sweeteners is worth the effort.
It’s always best to consume whole, unprocessed foods, including fruit, vegetables and plant-based sources of protein. They not only help reduce cancer risk but provide a host of overall health benefits.
What the WHO Says
The WHO actually released two reports on aspartame at the same time. The first report said aspartame is possibly linked to cancer — in other words, it is potentially harmful. The second said aspartame is generally safe unless consumed in very large amounts — that is, the actual risk is low.
The WHO cautions against jumping to conclusions, saying that the reports were primarily meant to encourage further research.
What’s been lost in the news is that the WHO reported in May there is little evidence artificial sweeteners help reduce body fat and they may increase risk of type 2 diabetes and heart problems.
What the FDA and Others Say
Aspartame was approved by the FDA as safe for use in food in 1981; since then, no evidence has emerged that’s compelling enough for the FDA to reverse its decision.
The FDA sets the acceptable daily intake of aspartame at 50 milligrams per kilogram of body weight per day and says approved sweeteners are safe when used in moderation That works out to a daily amount of around:
- 17-18 cans of diet soda
- 75 Equals or Nutrasweets
- 23 Splendas, Sweet Ones or Newtames
- 45 Sweet’N Lows
- 9 Truvias
That should be plenty for most people.
A 2022 study found that people who consumed higher amounts of aspartame had a slightly higher risk overall of developing cancer, especially breast cancer and obesity-related cancers. However, it is unclear precisely what amount of aspartame a person would need to consume over time to increase their risk of developing cancer.
Enjoy Sweeteners in Moderation
The news about aspartame is not something most people need to worry about. Being on the WHO’s list of possible carcinogens — a list that also includes aloe vera and Asian pickled vegetables — does not mean aspartame causes cancer. At most, there is limited evidence suggesting a possible link. It is hard to disprove that something is “possible,” and no strong connections between aspartame and cancer have been established despite decades of research.
Instead, recognize this as an opportunity to take action and reduce your cancer risk by making healthy dietary choices — the sooner, the better.
What I recommend to my patients is to moderate their intake of sugar and artificial sweeteners and eat a diet low in animal fat, low in processed foods and high in vegetables, fruits and whole grains.
If you consume aspartame regularly and are worried about its potential effects on your health, ask your physician for individualized guidance.
Misagh Karimi, M.D., is the director of clinical operations at City of Hope Newport Beach, and a medical oncologist specializing in gastrointestinal cancers at City of Hope Orange County Lennar Foundation Cancer Center in Irvine.