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Reasons To Avoid Aspartame At All Costs

min read

By Lauren MacDonald

Medically Reviewed by Julie Ching, MS, RDN, CDE

For years, diet soda seemed like the perfect alternative to regular soda, which is packed with an obscene amount of sugar and is super high in calories. You could drink diet soda sweetened with aspartame without feeling bad, and the taste was similar to the unhealthy alternative. But at what cost?

Recent sales of diet soda are taking a huge plunge–specifically, Diet Coke made by Coca-Cola–as the debate and controversy over aspartame reaches a new high. Experts have questioned whether aspartame is actually a good alternative to sugar and many now warn against the potential harmful effects it may cause. The safety of aspartame is being questioned, with studies linking the artificial sweetener to vision problems and headaches, among these ten reasons to avoid aspartame at all costs…

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Eye Problems

Some cases of eye pain, blurred vision, and dry eyes have allegedly been linked to aspartame consumption. In fact, even the FDA (U.S. Food and Drug Administration) has found a connection between aspartame ingestion and eye problems including decreased vision, according to several controlled studies.

Aspartame is made up of phenylalanine, aspartic acid, and methanol. The methanol is claimed to be potentially toxic to your retina and optic nerve, causing several forms of eye issues. There’s cause for concern when food and drink containing aspartame has been stored for long periods of time or exposed to heat–the breakdown of the components in aspartame may become toxic to your eyes.

Headaches and Migraines

Most people who suffer from headaches and migraines have triggers, and many of those triggers are something in their diet. Like chocolate, red wine, cheese and other common food and drinks, the Mayo Clinic identifies aspartame as a potential trigger for migraines.

Similar to caffeine and alcohol, it might not take much aspartame to cause regular headaches and migraines, and many doctors recommend cutting out diet food and drinks because of this reason. If you suffer from any form of headache, avoiding aspartame may help. For instance, products that trigger low blood sugar episodes shortly following consumption (i.e., diet soda) have been linked to migraines and also often contain the artificial sweetener.

Diabetic Issues

Though artificial sweeteners are a common alternative for those with diabetes, there’s enough controversy around aspartame that it may not be a good idea to consume it if you’re diabetic. Some studies suggest that aspartame might decrease insulin sensitivity. And a study done by the American Diabetes Association raises concerns that diabetics who eat meals with aspartame before exercise may see a drop in glucose levels.

According to research from the American Diabetes Association, artificial sweeteners do impact the body’s responses to sugar (glucose). This means that a diet high in artificial sweeteners can affect diabetes risk, even if the product contains zero calories from sugar. Due to studies like this one, many diabetes specialists feel that aspartame may not be a safe alternative to sugar, and suggest those with diabetes avoid it.

Prevention of Weight Loss

When you’re trying to lose weight, it’s common to look for foods that are low in carbohydrates and sugar, and there are many options readily available. However, low sugar items are typically sweetened with an artificial sweetener, like aspartame, that won’t necessarily help you lose weight.

In fact, processed diet foods may prevent weight loss–it’s believed that your body expects the carbs based on the taste of the food. When it doesn’t get them, it causes hunger pangs and binge eating. Instead of filling the sugar gap with diet items, eat fresh foods and drink water with lemon, lime or cucumbers so you get the carbonation you crave without the sugar.

Enhances Mood Disorders

Studies have shown that aspartame has adverse side effects on people who suffer from depression. It can enhance mood disorders, and one notable study was even stopped prematurely because the effects were so severe. If you suffer from or have a history of depression, your doctor should be aware of your diet, including any diet foods that contain aspartame.

The good news is, there has been no correlation between aspartame causing depression, but if you have a history of depression, you should stick to other artificial sweeteners or skip them all together. For instance, several studies published by the U.S. National Institutes of Health suggest that aspartame impacts neurobehavioral. One NIH study discovered that a group of healthy adults who consumed a high-aspartame diet for 8 consecutive days suffered increased irritable moods and greater rates of depression compared to those who consumed a low-aspartame diet.

Inflammation and Joint Pain

There have been several reports of joint pain and inflammation after consuming aspartame. It’s believed that many people are allergic to it–your body tries to protect itself from the chemical compounds found in the sweetener, resulting in an allergic reaction. Your soft tissues can become inflamed, causing pain and discomfort.

An allergen test can be done to confirm whether you’re allergic to aspartame, and the only treatment is to eliminate it completely from your diet. If you’re prone to joint pain and inflammation, avoid aspartame. According to research compiled from Arizona State University, 551 patients who consumed moderate to large amounts of aspartame experienced systematic joint pain so severe that they required analgesics.

Stomach Cramps

When aspartame first came on the market in soft drinks in the early 1980’s, the FDA received a lot of complaints about side effects and reactions to it. Stomach cramps were a common complaint, especially in the first year the diet products hit the shelves. Today, a lot of people who suffer from abdominal pain and stomach cramps claim that once they remove artificial sweeteners from their diet, specifically aspartame, their symptoms go away. And it seems that there are no lasting effects once this diet change is in place.

Research compiled by the University of Iowa found that high aspartame diets had a biphasic effect on appetite, meaning high levels of aspartame caused a short term drop in hunger followed by a spike in hunger that increased as the concentration of the sweetener increased. Researchers dubbed this ‘sweetness’ increased hunger.

Increased Risk of Seizures

According to, aspartame is the number one food item that the FDA receives complaints about. It is believed that as much as 30-percent of people are sensitive to aspartame. Interestingly, there are over a thousand cases of pilot complaints about aspartame, with seizures topping the list.

It’s possible that the methanol in aspartame and found in diet soda causes a more severe toxic reaction when consumed at high altitudes, such as on a plane. The other theory is that pilots consume more diet soda during flight, increasing the possible side effects like seizures.

Hearing Problems

The FDA has a list of around 90 documented symptoms related to aspartame consumption. Hearing loss, ringing and buzzing in the ears, and noise intolerance are a few of those symptoms. Tinnitus is a debilitating ringing the ears and has also been a commonly reported issue by people who consume diet soda. The hearing loss associated with cases of tinnitus can be permanent.

Several scientific studies, including studies by the U.S. Food and Drug Administration (FDA), report that aspartame negatively impacts vestibular and cochlear functioning, which can begin with tinnitus (or a chronic ringing in the ears) and gradually develop into high frequency hearing loss. The good news is that it seems as if most of the other hearing issues linked to aspartame consumption are fixed by simply avoiding it.

Controversial Cancer Studies

Aspartame has allegedly been linked to some forms of cancer. While it’s been approved for use by the FDA and since its use in food is controlled, concerns continue to mount over how your body absorbs aspartame. Unlike other popular artificial sweeteners, your body metabolizes aspartame when you ingest it, changing its compounds.

While government agencies say their studies show no link between aspartame consumption and cancer, it’s claimed that non-government funded studies do show a link, specifically to brain tumors. Even though 2 studies published by a group of Italian researchers (and cited by the American Cancer Association) link high levels of aspartame consumption to a heightened risk of certain blood-related cancers (i.e., lymphomas and leukemias) in rats, the FDA states that important data is lacking.


Julie Ching is a Registered Dietitian and Certified Diabetes Educator in Los Angeles. She decided to become a Dietitian after traveling through Europe, South America, and Asia and discovered a passion for food. She now works with people of all ages and varying disease states to improve their health. She is passionate about teaching people about nutrition so they can live their best life while still considering their cultural and socioeconomic backgrounds.

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