After even conventional wisdom had to admit that soda pop could not be healthy due to the sugar content, sweeteners experienced an ongoing high.
Many people reach for zero and diet versions of their favorite soft drinks because they contain hardly any carbohydrates or calories.
Whether the side effects of aspartame in these drinks are less harmful than sugar is what this article tries to find out based on actual science.
Does Aspartame Spike Insulin?
As a decades-old ingredient in diet soda, aspartame, or additive number E951 on European food labels, is probably the best-known sweetener.
It is a sugar-free and low-calorie artificial sweetener.
Moreover, the sweetener is indispensable in most global manufacturers’ light and zero drinks. You can also find aspartame as an ingredient in the following packaged sweeteners:
- Sweet n’ Low
With this in mind, aspartame is also probably the most widely used synthetic sweetener.
The reason aspartame is often considered harmful is that numerous studies have linked the sweetener to potential dangers.
Here is a sampling of those problems associated with aspartame:
- Alzheimer’s disease (Humphries et al. 20081)
- Anxiety and depression (Choudhary et al. 20182)
- Diabetes (Swithers 20133)
- Epilepsy (Camfield et al. 19924)
- Fibromyalgia (Ciappuccini et al. 20105)
- Cardiovascular disease (Gardener et al. 20126)
- Metabolic syndrome (Dhingra et al. 20077)
- Parkinson’s disease (Abhilash et al. 20138)
In addition to these potential long-term side effects, let’s look at what the consumption of aspartame might be causing in our bodies in the short term.
Is Aspartame Bad for You?
After consumption, aspartame breaks down into three chemical compounds, the first two of which are amino acids (Humphries et al. 20089):
- Aspartic acid
While phenylalanine in natural foods such as soybeans, peas, or pumpkin seeds is considered safe by most health authorities, it can be toxic in large doses.
And diet soda, in particular, can put large amounts of phenylalanine into the body.
Since the amino acid phenylalanine is chemically bound in aspartame, the human body can absorb it quickly.
Due to its ability to convert to free methanol under elevated temperatures, the third chemical compound in aspartame is exceptionally problematic.
Once it is in this state, methanol can easily convert to formaldehyde.
Formaldehyde is a carcinogen that can cross the blood-brain barrier, a filter made of capillaries that transport blood to the brain and spinal cord.
Therefore, researchers conclude that aspartame consumption may be harmful because of its contribution to forming formaldehyde adducts (Trocho et al. 199810).
For this reason, drinking zero and light beverages may be more of a concern than we thought. Is aspartame, therefore, possibly more harmful than sugar itself?
In the end, most people consume sweeteners to lose weight. I have always wondered why so many overweight people drink diet coke.
Did they start drinking diet beverages only after gaining weight, or perhaps they gained weight because of diet sodas?
To answer this question, we need to look closely at the hormone responsible for weight gain – the storage hormone insulin.
Does Aspartame Cause an Insulin Response?
Nowadays, researchers can predict about 75% of overweight people’s gain and loss with insulin levels (Kong et al. 201311).
Ultimately, the storage hormone can store supplied energy your body doesn’t consume immediately.
Against this background, it quickly becomes apparent that it is not only blood glucose that matters. Although a glucose spike stimulates insulin secretion, it is not the only possible cause.
That’s why losing weight is not just about sugar or calories – a small but game-changing fact state-of-the-art diets such as the ketogenic diet take into account.
Instead, high insulin levels pave the way for fat gain.
With numerous studies concluding that artificial sweeteners are a cause rather than a countermeasure of the current obesity epidemic, we must look at their effect on the storage hormone (Fowler et al. 200812).
Aspartame vs. Sugar
Aspartame is the classic sweetener in diet soda. Unlike sugar, it provides virtually no carbohydrates or calories.
Therefore, aspartame cannot raise blood sugar levels as abruptly as sugar. But that doesn’t necessarily mean the artificial sweetener can’t raise insulin levels.
With this in mind, one study concluded that aspartame could raise insulin levels more than regular table sugar.
Thirty minutes after consumption, the meal sweetened with aspartame caused an absolute peak insulin level that table sugar could not reach (Anton et al. 201013).
According to this study, among other potential side effects, this sweetener prevents fat burning.
Furthermore, this means that beverages sweetened with aspartame can break a fast due to their insulin response.
Even more impressive is that a recent study found the average increase in insulin and blood glucose levels over three hours to be the same with aspartame as sugar consumption (Tey et al. 201714).
Thus, traditional diet sodas do not even provide the hoped-for benefit for blood glucose regulation in the long term.
Apart from the advantage of not containing fructose, aspartame is also as harmful as sugar in this comparison.
Aspartame vs. Stevia
Stevia is praised because it is plant-based, sugar- and calorie-free. Nevertheless, like table sugar, it is highly processed and refined from a plant source.
Therefore, the legitimate question arises whether green soda drinks are a better alternative to conventional diet soda.
Based on a well-known study, people repeatedly claim that stevia does not affect blood sugar or insulin levels.
Table sugar indeed causes much higher glucose and insulin spikes immediately after consumption. Moreover, the same values are also slightly higher with aspartame than with stevia.
But even this much-cited study shows that the values change after about 90 minutes. From this point on, blood glucose and insulin levels are higher after stevia consumption than after sugar or aspartame (Anton et al. 201015).
In contrast to this study, a more recent study compared these sweeteners’ effects over three hours instead of just two hours.
Also, the subjects in this study consumed sweetened beverages, not meals. The researchers found no significant differences between table sugar, stevia, and aspartame over three hours.
Although sugar initially caused higher responses, stevia’s insulin production could catch up throughout the three hours and match overall insulin levels.
It is also perplexing to note that blood glucose levels also increased in the same proportion. Ultimately, no difference existed on average between sugar, aspartame, stevia, and monk fruit for this value (Tey et al. 201716).
The bottom line is that stevia may have a slight advantage over aspartame and conventional sugar due to lower initial spikes. Still, natural sweetener is also far from ideal for weight loss.
Aspartame vs. Sucralose
Besides aspartame, there are two ubiquitous artificial sweeteners: acesulfame-K and sucralose.
They both provide no carbohydrates, proteins, or calories.
Sucralose is a significant compound in Splenda, a sweetener sold in sugar-like pink packets. On food labels, you’ll also find sucralose among ingredients by its E-number, 955.
A study published in the journal Diabetes Care compared drinking water with and without sucralose.
The oral intake of the sweetened beverage increased the test subjects’ insulin levels by up to 50 percent (Pepino et al. 201317).
Thus, this synthetic sweetener also has a significant effect on insulin production. But what makes sucralose just as harmful as aspartame is its impact on gut health.
According to research, a single packet of the sucralose-based sweetener Splenda is enough to wipe out 50 percent of the healthy gut microbiome (Abou-Donia et al. 200818).
With this in mind, it is even more perplexing that even the supposedly natural sweetener stevia can negatively impact your gut health (Ruiz-Ojeda et al. 201919).
Aspartame vs. Aceulfame Potassium
The more heat-resistant sweetener acesulfame potassium or short acesulfame-K with the E-number 950 is a standard part of commercially available beverages.
It is usually found with aspartame in zero-sugar or sports beverages. Although acesulfame-K is also calorie-free and sugar-free, it also stimulates insulin secretion.
In this context, researchers have even found that acesulfame potassium increases insulin levels to the same extent as the same amount of glucose (Liang et al. 198720).
For this reason, being sugar-free does not automatically mean being healthy. Against this background, zero drinks are eventually not better than diet soda.
Aspartame is usually found in both variants anyway.
Dangerous Side Effects of Aspartame
Although it may sound controversial that a sugar-free, low-carb soda could be worse for you than classic pop, there are probably good reasons for this.
Studies that have examined the effect of aspartame on individual diseases show the dangers it can pose to health.
Promotes Cardiovascular Diseases
Cardiovascular diseases are currently the top cause of death throughout the Western world.
Moreover, problematic cardiovascular health is prevalent in those countries that consume masses of diet soda. Therefore, it is not far-fetched that sweeteners could contribute to this outcome.
With this in mind, the Women’s Health Initiative observed 59,614 women over 8.7 years. The results showed that those who drank two or more diet sodas daily developed a 30 percent higher risk of cardiovascular events (ACC 201421).
Accordingly, a University of Miami study also showed a 43 percent increase in strokes and heart attacks from regularly drinking diet drinks (Gardener et al. 201222).
Supports Diabetes and Metabolic Syndrome
Artificial sweeteners can also affect metabolism.
If the brain is waiting for a sweet taste and glucose, but you consume a low-calorie sweetener, this can spur cravings for sweets even more (Yang 201023).
For this reason, long-term consumption of intense artificial sweeteners can cause metabolic syndrome and type 2 diabetes (Swithers 201324).
Accordingly, the Framingham Heart Study also states that the likelihood of developing metabolic syndrome is about 50 percent higher among consumers of diet beverages (Dhingra et al. 200725).
Cancer is another disease of uncontrolled growth that continuously plagues our Western society. When we talk about aspartame, there is a prevalent opinion that this sweetener can cause cancer.
Against the backdrop of aspartame’s reckless consumption over the past 30 years, researchers have studied the connection between the sweetener and cancer.
The Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation conducted a long-term study on aspartame in 2005.
The researchers concluded that aspartame was a multipotential carcinogen (Soffritti et al. 200626).
Increases Mental Health Risks
The results of studies examining mental health came to concerning conclusions.
One study showed that the risk of depression was increased in those who drank diet soda instead of regular soda (Guo et al. 201427).
Additionally, another study found that people with mood swings are susceptible to aspartame and should, therefore rather, avoid it (Walton et al. 199328).
Also, aspartame can increase the stress hormone cortisol and free radicals in the body.
Since this fact increases the brain’s susceptibility to oxidative stress, aspartame may negatively affect neurological health (Choudhary et al. 201829).
Promotes Kidney Diseases
There are other findings that we might not have suspected in the context of diet drinks.
For example, researchers studied the kidney function of 3,318 women concerning sweetener consumption.
As a result, just two diet sodas per day could double the decline in women’s healthy kidney function (Lin et al. 201130).
For this additional reason, diet soda is not only unhealthy but is most likely more harmful than sugar-sweetened beverages.
Aspartame Spikes Insulin Among Other Side Effects
If you summarize scientific findings or even simple statistics, you have to conclude that aspartame can’t help you lose weight.
Likewise, serious concerns arise regarding the standard sweetener in metabolism, heart health, kidney disease, mental health, or even neurodegenerative diseases.
Yes, aspartame has been used worldwide for over 30 years. As mentioned above, the extent of the diseases has significantly increased over this period.
The side effects of aspartame and diet soda have probably played their part in this development.
Aspartame Insulin Response and Side Effects FAQ
Is aspartame bad for you?
Aspartame can harm metabolism, heart health, or even kidneys.
Is aspartame poisoning?
Aspartame is not a neurotoxin. However, aspartame consumption can harm the brain due to its contribution to forming formaldehyde adducts.
Where is aspartame found?
You can find aspartame in zero and diet drinks 🥤 and sweeteners 🍬 such as Splenda or Nutrasweet.
Can aspartame cause cancer?
In contrast to other side effects, science has not yet proven that aspartame is carcinogenic.
Can You Consume Aspartame While Pregnant?
Since the risks of aspartame are already dangerous for a healthy person, it is probably not a good idea to consume it during pregnancy.
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Mag. Stephan Lederer, MSc. is an author and blogger from Austria who writes in-depth content about health and nutrition. His book series on Interval Fasting landed #1 on the bestseller list in the German Amazon marketplace in 15 categories.
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