WHO labels aspartame as 'possible carcinogen', but FDA disagrees
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Aspartame is a "possible carcinogen", a World Health Organization unit has ruled, but a joint panel found that the sweetener remains safe to consume at levels in accordance with existing guidance.
While WHO's International Agency for Research on Cancer (IARC) said aspartame is a "possible carcinogen" based on limited evidence, the WHO/FAO Joint Committee on Food Additives (JECFA) reaffirmed the acceptable daily intake of 40 mg/kg body weight as there was no sufficient reason to change this limit.
"We're not advising consumers to stop consuming (aspartame) altogether," said Francesco Branca, WHO's nutrition director. "We're just advising a bit of moderation." 
The FDA disagreed with IARC's conclusion that studies support classifying aspartame as a possible carcinogen as the studies have significant shortcomings. 
"Aspartame being labeled by IARC as 'possibly carcinogenic to humans' does not mean that aspartame is actually linked to cancer," an FDA spokesperson said. "FDA scientists do not have safety concerns when aspartame is used under the approved conditions."
Note that the IARC did not factor in how much of the popular artificial sweetener, used in Diet Coke and other low-calorie food products, an individual can safely consume.
The use of aspartame in food products has been debated for decades, pushing some companies to remove the sweetener from their products. PepsiCo (PEP) eliminated the use of aspartame in its diet sodas in 2015, but brought it back a year later.
Earlier in May, the WHO recommended against the use of non-sugar sweeteners to control body weight.
Stocks to watch: Coca-Cola (KO), PepsiCo (PEP) and Dr Pepper/Snapple (KDP), Mondelez (MDLZ), Britvic (OTCQX:BTVCF).
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