Jul 3, 2023

Aspartame: how bad can it be?

In the realm of food additives, few have stirred as much controversy and debate as aspartame. With its widespread use as a sugar substitute in over 6,000 products, from diet sodas to chewing gum, aspartame has long been a subject of scrutiny and concern.

Just a few days ago, the International Agency for Research on Cancer (IARC) declared it “possibly carcinogenic to humans.” While this news captivated the public’s attention, and received significant press coverage, it’s worth noting that the potential cancer risk represents just a fraction of the health issues associated with aspartame.

Delving beyond the headlines, let’s explore the full story, so you can make informed decisions about how to safely sweeten your food and drinks. We’ll also share sweet solutions you can safely enjoy, without negatively impacting your health.

Establishing Trust or Creating Confusion?

In 1965, the International Agency for Research on Cancer (IARC) was established by the World Health Organization (WHO) to evaluate potential carcinogens, and issue classifications to guide public health policies. Although their declarations generate significant headlines, they have been criticised for the reliability of their advicei, industry influenceii and the (lack of) action taken based on their evaluations.

The IARC’s classifications are based on evaluations of scientific research, including epidemiological studies, animal experiments, and mechanistic data. However, they don’t convey the level of risk, they simply focus on establishing the potential for causing cancer. Their evaluations also incorporate studies with limited sample size, conflicting results, and low-quality methodologies.

The lack of trust in their findings leads to varying interpretations by different scientific bodies, and (industry-funded) public debates that create public confusion. News coverage of IARC’s pronouncements includes ‘clickbait’ headlines which exclude important details (like the relevance of meat quality in their 2015 conclusion that meat and cancer were associated).

Similar warnings from the IARC placed on red meat, working overnight, and using mobile phones have faced criticism for sparking alarm over hard to avoid substances or situations. Cancer Research UK explicitly states that artificial sweeteners such as aspartame don’t cause cancer.


So, what’s going on? Is aspartame dangerous or not?

Vague Advice and Information Overload

The IARC classifications use vague terms like “possibly carcinogenic” and “probably carcinogenic” or “probably not carcinogenic”. These non-committal definitions avoid legal ramifications, but don’t effectively guide the public towards making healthier decisions.

Overloaded with information, and a growing list of what ‘can’ impact health, it’s increasingly difficult for people to evaluate what to avoid, and what to focus on. The lack of ‘scale’ makes it impossible to take action and there is no guidance on which carcinogens are worse. There is no official ‘Top 10 Carcinogens you can avoid’ that could help guide healthier shopping lists!

The result of this controversy and confusion is inaction. We can’t effectively evaluate how dangerous it is, so we mentally move onto the next problem. Our ability to ignore issues we can’t understand is harnessed by industries with vested interest in the status quo.  Tainted news coverage adds to the overwhelm and we can’t fathom who to trust, or understand the risks involved.

Public health authorities should be deeply concerned that this leaked opinion contradicts decades of high-quality scientific evidence and could needlessly mislead consumers into consuming more sugar rather than choosing safe no- and low sugar options – all on the basis of low-quality studies.”



So, what’s the answer? How can you make informed decisions about your health? The answer is simple, take a look at the bigger picture. Forbes doesn’t mention that there are many other safe sugar alternatives, it’s not black and white ‘aspartame or nothing’.

Let’s take a look at the evidence against aspartame, then delve into some tasty alternatives that you can trust.


What is Aspartame, and Who Funds the Research?

Aspartame was discovered accidently in the 1960s, by chemist James Schlatter while working on an anti-ulcer medication, it was approved as a food additive in the 1980s. Chemically, aspartame is two amino acids (L-phenylalanine and L-aspartic acid) plus a methyl ester group, which provides the sweetness. 

Aspartame’s commercial success is due to its intense sweetness (about 200 times sweeter than table sugar) and its low-calorie content. Following growing sugar awareness, aspartame became an attractive option for manufacturers to reduce sugar content, and the global aspartame market is now worth about $400 million per year.v

It took Searle, the manufacturer, 16 years to get aspartame approved as a food additive in the United States, and they were under investigation for performing fraudulent studies. Aspartame was suddenly approved in 1981 when Donald Rumsfeld, former CEO of Searle and new member of President Ronald Reagan’s transition team, appointed a new FDA commissioner.vi Currently, the State of New Mexico is attempting to ban aspartame, it’s banned in Japan and discouraged in China. vii

Most of the research into the effects of aspartame is paid for by the food industry itself, which introduces obvious bias, as reported by the peer-reviewed open access journal published by the Public Library of Science (PLOS):

100% of the industry-sponsored studies concluded that aspartame was safe, and 92% of the independently funded studies identified adverse effects of aspartame consumption”.viii

They also found that 42% of reviews had authors that did not disclose conflicts of interest, and one-third failed to reveal any source of funding. Sadly, these deceptive tactics are not uncommon, the sugar lobby has a long track record of funding research that points the finger at everything but sugar, influencing public perceptions, and preventing health professionals from taking effective and accurate action.ix

The Real Problems with Aspartame

Decades of independent research has linked aspartame to serious side effects and debilitating conditions:

Cancer: a 2022 French cohort study of 102,865 adults found that aspartame was associated with an increased cancer risk (specifically breast cancer). In 2012 Harvard researchers reported an association between aspartame intake and increased risk of cancer (non-Hodgkin lymphoma, multiple myeloma and leukaemia).x

Heart Disease: A 2017 Canadian meta-analysis reported “increases in weight and waist circumference, and higher incidence of obesity, hypertension, metabolic syndrome, type 2 diabetes and cardiovascular events.” A 2016 paper found “significantly increased weight gain, adiposity, incidence of obesity, cardiometabolic risk, and even total mortality among individuals with chronic, daily exposure to low-calorie sweeteners – and these results are troubling.”xi

Neurological Issues: Consuming diet sodas leads to a three-fold increase in risk for stroke and dementia. Blood vessels in the brain become blocked also increasing the risk of Alzheimer’s. The methyl group in Aspartame metabolises to formaldehyde (which is linked to Alzheimer’s and shown to cause memory loss in animal studies). Higher doses of aspartame are also associated with seizures in humans and animals. xii

Mental Health: Aspartame has been linked to irritability, depression, insomnia, and anxiety while inhibiting our ability to learn (in both human and animal models). In animal studies higher doses of aspartame causes major neurochemical changes and low doses exhibit neurotoxic effects.xiii

Kidney Function: Drinking more than two drinks per day containing aspartame is associated with a decline in kidney function.xiv

Metabolic Issues: Considering it is marketed as an alternative to sugar many people are shocked to find out that studies link aspartame to increased appetite, metabolic dysfunction, weight gain and diabetes. Aspartame appears to block intestinal enzymes, and kill specific gut bacteria, thereby preventing weight loss. It also increases insulin resistance and reduces our ability to effectively process glucose.xv

Hormones and Fertility: Aspartame has been shown to increase the risk of pre-term births and is associated with babies being born already overweight. It is associated with the early onset of menses (female puberty) and damage to sperm (in rats).xvi

Liver Damage: Animal studies have shown an association with aspartame and injury to the liver, specifically reducing the naturally protective anti-oxidant glutathione. Aspartame elevates glucose in the liver, and is associated with degeneration, infiltration, necrosis, and fibrosis.xvii

Based on this list of extensive issues from human and animal studies, the IARC classification of “possibly carcinogenic” seems irrelevant! Considering aspartame does not prevent the problems associated with classic sugars (namely obesity and diabetes) why take the risk when there are much safer alternatives?

Effectiveness and Genuine Alternatives

On May 15, 2023, the WHO released new guidelines advising people “not to use non-sugar sweeteners (NSS) for weight control.” xviii Their review points out that “consumption of non-sugar sweeteners is associated with increased risk of type 2 diabetes, cardiovascular diseases and all-cause mortality, as well as increased body weight.” So, that pretty much seals the deal. It’s simply not worth the risk, and they don’t work!

Artificial and non-nutritive chemical sweeteners are not natural, they confuse the body and are poorly metabolised. The sweet taste without enzymes to process it causes metabolic chaos. We evolved our relationship with sweet foods over millions of years, it’s simply not possible to ask the body to deal with a foreign substance with no genetic history.

Fortunately there are safer sugars that the body does know how to process, but they have far fewer calories, don’t spike insulin, and provide sustained energy. Until relatively recently these ‘rare’ but sweet and safer alternatives were simply not known about or marketed. But the pioneering work of research scientist Dr. Johannes Coy has established a set of sweet options that you can trust!

Safer Sweet Options to Enjoy

Galactose: Used as a food source for thousands of years, this sugar plays a crucial role in brain development. It is found in breast milk and supports the growth of the brain’s memory centre. Galactose contains 25% fewer calories than table sugar and has a lower glycaemic index than glucose, making it a favourable option for maintaining stable energy levels throughout the day. Fermented dairy products like yogurt and kefir are good sources of galactose.

Tagatose: Derived from lactose it has a sweet taste similar to sugar. It is naturally present in dairy products and fruits and has a low glycaemic index, helping to prevent spikes in blood sugar levels. Tagatose is metabolized differently than other sugars, leading to its unique properties. It is broken down into glucose and fructose at a much slower rate, contributing to its lower glycaemic index and reduced caloric impact. Studies suggest that tagatose supports weight loss and blood sugar control with prebiotic effects that stimulate beneficial gut bacteria.

Trehalose: This naturally occurring sugar is found in foods like mushrooms, yeast, and honey. It has a caloric content similar to table sugar but a slightly lower glycaemic index. It offers about 45% of the sweetness found in regular sugar. Trehalose displays potential health benefits, including protection against oxidative stress and improved immune function. It is also used in the food industry as a preservative and flavour enhancer.

Isomaltulose: Derived from beet sugar, and naturally found in honey and sugarcane it provides a slow and steady release of energy due to its low glycaemic index. Isomaltulose is digested and absorbed gradually, avoiding rapid spikes in blood sugar levels. It offers the same caloric value as table sugar but with a lower glycaemic index providing sustained energy with potential benefits for athletic endurance and cognitive performance.

Ribose: Found in every living cell and plays a crucial role in cellular energy production and the synthesis of DNA and RNA. It is naturally present in foods like meat, dairy products, and vegetables. Ribose fuels cells with energy and has a caloric value similar to table sugar but a less pronounced sweetness. Ribose is metabolized through a pathway that generates ATP, the primary energy currency of cells and has shown promising results in improving exercise performance and recovery.

Erythritol: Erythritol is a sugar alcohol found in select fruits and fermented foods. It is a low-calorie sweetener that provides approximately 70% of the sweetness of table sugar with only 6% of the calories. Erythritol is unique in that it is absorbed in the small intestine and excreted unchanged. It is considered safe for consumption and may possess antioxidant properties, but excessive consumption can lead to gastrointestinal discomfort.

Together these incredible sugars provide a practical and safe alternative to our current excess of glucose, sucrose and fructose. They have health benefits, not risks, and since they are completely natural the body knows what to do with them.

Increasing awareness of their incredible potential, and delicious, sweet taste, is growing. The European Food Standards Agency has officially recognized that Isomaltulose, Tagatose and Erythritol actively protect your teeth (contributing to the maintenance of tooth mineralization) and induce a lower blood glucose rise compared to sugar containing food and drinks.

Finally, it is possible to enjoy guilt-free sweet treats that provide sustained energy!

Are you ready for an Intelligent Sugar Strategy?

Are you ready for an Intelligent Sugar Strategy?

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