Daily Early-Life Exposures to Diet Soda and Aspartame are Associated with Autism in Males: A Case-Control Study

Daily Early-Life Exposures to Diet Soda and Aspartame are Associated with Autism in Males:
A Case-Control Study

Nutrients

August 29, 2023, Vol. 15; No. 17; Article 3772

Sharon Parten Fowler, David Gimeno Ruiz de Porras, Michael D. Swartz, Paula Stigler Granados, Lynne Parsons Heilbrun, Raymond F. Palmer: from the University of Texas Health Science Center. This study cites 121 references.

This is the first study to specifically examine the associations between offspring autism status and the daily maternal intake of diet soda (DS) and aspartame (ASP) during pregnancy/breastfeeding.

A total of 356 children were included in the analyses, adjusted for child’s ethnicity, mother’s education, and household income.

Maternal intake of ≥12 ounces (1 can) of DS/day during pregnancy/breastfeeding was the primary exposure variable.

The authors hypothesized that gestational/early-life exposure to ≥1 DS/day (DS-early) or aspartame (ASP-early: ≥177 mg/day) increases autism risk.

KEY POINTS FROM THIS ARTICLE:

1) Aspartame is the leading sweetener in U.S. diet sodas (DS).

2) Aspartame has been reported to cause neurological problems in some users.

3) “In prospective studies, the offspring of mothers who consumed diet sodas/beverages (DSB) daily during pregnancy experienced increased health problems.”

4) “Our findings contribute to the growing literature raising concerns about potential offspring harm from maternal DSB/aspartame intake in pregnancy.” [Key Point]

5) “Over the past 40 years, the prevalence of diagnosed autism spectrum disorder (ASD) in the U.S. has dramatically risen, from fewer than 0.3 per 1000 children diagnosed with autism before 1980 to 27.6 per 1000 children diagnosed with ASD in 2020.” [Wow!!]

• ASD prevalence has reached unprecedented proportions, with males being disproportionately affected.
• “Autism prevalence among boys is almost quadruple that among girls, and a recent study estimated that approximately 1 in 23 U.S. boys aged 8 years or older in 2020 had been diagnosed with ASD.” [Key Point]

6) “The degree to which ASD diagnoses have risen during this time highlights the potential role of non-genetic influences, including early prenatal exposures to heavy metals, organophosphate pesticides, and other environmental toxins, in offspring autism risk.”

7) “Maternal diet during pregnancy and breastfeeding represents an important additional non-genetic influence on offspring autism risk.”

8) Maternal intake of prenatal vitamins, folic acid, omega-3 fatty acids, and vitamin D reduce offspring autism risk.

• These nutrients may exert neuroprotective effects during development.

9) Maternal dietary intake of methanol during pregnancy increases the risk of autism in their offspring (methanol is not found in alcoholic beverages, which contain ethanol; methanol is found in aspartame).

• “The dietary intake of methanol during pregnancy was approximately twice as high among biological mothers of children with ASD as among mothers of neurotypically developing children.” [Important]
• “Aspartame, a leading non-nutritive sweetener (NNS) in the U.S., is a ubiquitous source of dietary methanol in this country, and aspartame-sweetened products constituted the major source of dietary methanol.”
• “Pregnant women might unknowingly be exposing their unborn children to an increased autism risk through their consumption of aspartame-sweetened diet products during pregnancy and is of particular concern.”

10) “In 1981, the U.S. Food and Drug Administration (FDA) approved the use of aspartame as a tabletop sweetener and, in 1983, as an ingredient in diet sodas (DS) and other products.”

• “Aspartame rapidly became the leading DS sweetener used in the U.S; DS consumption doubled, and aspartame consumption increased 17-fold, over the next 8 years.”
• “By the end of 1983, the FDA had received numerous complaints of adverse reactions among aspartame consumers.”
  • “Prominent complaints included headache, anxiety, and depression.”
• “These and other neurological problems—including irritability, mood disorders, cognitive problems, and seizures—were subsequently reported to be increased among users of diet sodas/beverages (DSB) and other aspartame-sweetened products, which are leading vehicles of aspartame intake in the U.S.”

11) “Aspartame is metabolized in the intestine into aspartic acid, an excitatory neurotransmitter; phenylalanine, which is involved in neurotransmitter regulation; and methanol, the metabolites of which include formaldehyde, formate, and other toxins.”

• “The adverse neurological impacts following the consumption of aspartic acid, phenylalanine, and/or aspartame include changes in neurotransmitter levels and excitotoxicity, with adverse impacts on neuron function/survival.”
• “Humans are uniquely vulnerable to methanol, the blood levels of which rise following aspartame consumption.”
• “Exposures to methanol and formaldehyde resulted in increased neuronal apoptosis, neurodegeneration, and cognitive problems.”

12) Aspartame intake has been associated with long-term health problems.

• “Prominent among these is a recurring finding of the markedly decreased availability of the reduced form of glutathione [GSH].”
  • “This finding is crucial because GSH protects the developing brain by providing antioxidant defense against oxidative stress, by scavenging toxins, and by supporting methylation processes.”
• Aspartame increases levels of free radicals, oxidative stress, lipid peroxidation, inflammation, and mitochondrial dysfunction; increased permeability of the blood–brain barrier (BBB); excitotoxicity and neuronal apoptosis.
  • These adverse impacts are attributed to methanol.

13) The risk of autism is four times higher in boys than in girls.

14) Intake of the three leading non-nutritive sweeteners (NNS) are:

• Equal/Nutrasweet (blue, aspartame)
• Splenda (yellow, sucralose)
• Sweet’N Low (pink, saccharin)
• One 12-oz. can of soda sweetened with aspartame contained ≥177 mg of aspartame/can.
• A tabletop packet contains 37 mg of aspartame.

15) Results

• Autism diagnosis in boys is associated with more-than-tripled odds with early-life exposure to either ≥1 DS/day or comparable daily aspartame exposure (≥177 mg/day).

16) “Diet sodas and other diet beverages (DSB) are leading vehicles of aspartame intake in the U.S.”

17) Prior studies have shown that maternal aspartame is associated with adverse neurological reactions, increased headache, problems with nervousness/irritability, depression, memory, spatial orientation, and increase in major depression.

• A study of 318,257 participants in the National Institutes of Health-American Association of Retired Persons followed for >10 years, found that the incidence of depression was significantly higher among consumers of aspartame-sweetened tea and coffee.
• In a study of 1,484 older members of the Framingham Heart Study Offspring cohort followed over a decade, the incidence of Alzheimer’s disease was nearly tripled among participants with cumulative DS consumption ≥ 1/day.

18) Between 24% and 30% of pregnant women use either NNSs in or DS/DSB during their pregnancies.

• There is direct evidence of transplacental passage of NNSs in humans.
• “[There is a] troubling concern of the possible dose accumulation of NNSs within the fetus.”

19) One of the most frequently reported impacts of aspartame consumption is a decrease in the availability of GSH.

• “A decreased GSH and increased oxidative stress, mitochondrial dysfunction, inflammation, dysbiosis of the gut microbiota, and leaky gut were also observed in both animals fed aspartame and individuals with autism.”
• Early-life aspartame exposure could increase toxicant load while simultaneously decreasing neuroprotective potential.
• These substances cross the placenta, “and raised troubling questions regarding the dose accumulation of non-nutritive sweeteners within the fetus.”

20) Conclusions

• “Compared with male controls, males with autism in our study had more than tripled odds of having been exposed daily—gestationally and/or through breastfeeding—to either diet soda itself or comparable doses of aspartame from multiple sources.”
  • “The possibility that early-life exposures to these products through maternal diet might increase offspring neurodevelopmental risk—at least among boys—is of particular concern.”
• “Between 24% and 30% of pregnant women reported using either non-nutritive sweeteners in general or diet sodas and other diet beverages specifically during their pregnancies.”

We have reviewed these articles that support the adverseness of the consumption of aspartame:

Article Review 4-13:
Diet Soft Drink Consumption is Associated with an Increased Risk of Vascular Events in the Northern Manhattan Study
Journal of General Internal Medicine

Article Review 15-13:
Fueling the Obesity Epidemic? Artificially Sweetened Beverage Use and Long-term Weight Gain
Obesity

Article Review 25-15:
Gain Weight by “Going Diet?” Artificial Sweeteners and the Neurobiology of Sugar Cravings
Yale Journal of Biology and Medicine

Article Review 28-15:
Consumption of Artificial Sweetener– and Sugar-containing Soda and Risk of Lymphoma and Leukemia in Men and Women
American Journal of Clinical Nutrition

Article Review 16-17:
Sugar- and Artificially Sweetened Beverages and the Risks of Incident Stroke and Dementia
Stroke