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ASK THE NUTRITIONIST: Sugar-free sweeteners: Good or bad?

We’ll review sweeteners one at a time, this week looking at the artificial ones and next week the more natural alternatives

Dear Readers,

When asked about sugar and weight loss, the discussion invariably turns to sugar addiction and sugar-free sweeteners. For a past column on how to beat sugar addiction, go here. The good news is we have more options now than ever for sugar-free sweeteners! The bad news is all those options can be confusing! Is it the sugar that’s the problem or the calories or the carbohydrate content? Which ones are best for your health issues? Are artificial sweeteners safe? Are there any sugar-free sweeteners that don’t taste bitter and are easy to cook with? Well, this is exactly what we’re going to discuss over the next two weeks, so you will have a much clearer picture by the time we’re done!

We’ll review sweeteners one at a time, this week looking at the artificial ones and next week the more natural alternatives. But first let’s look at why we want sugar-free. Let’s be honest, nothing I’ve tried tastes exactly like white or brown sugar, although some come close. So why bother at all? Is it really that important for health?

Actually, yes, it really is. Diabesity/metabolic syndrome is the number one health concern of our time. This refers to increased blood pressure, heart disease, stroke, high blood sugar, insulin resistance and Type 2 diabetes, excess body fat around the middle, obesity, and abnormal cholesterol and triglyceride levels.

Cancers are also related to this cluster of health concerns. Even children are now showing signs of this. And we know Covid-19 outcomes were far worse for those with pre-existing metabolic syndrome (source) (source). So it really is an important decision.

The Problem with Sugar

The amount of sugar and carbohydrates that we have access to today is multiple times more than what we historically had access to. At the same time, our activity levels have dropped substantially. These foods cause an overload not only of calories, but perhaps more importantly, of sugar in the blood, as all carbs are broken down to sugars in the body. Even whole grain foods and “healthy” starchy veggies are broken down into sugar in the body. When our muscles aren’t using those sugars for movement (not much is needed) and there is excess sugar over time, we develop the conditions above.

The secret then, is to increase our activity levels and keep blood sugar within a normal range. To do this, we regulate how much sugar and carbohydrates we eat, in relation to how much we move around and exercise. We focus more on protein, nutrient dense veggies and fruits, and healthy fats.

So it’s not just sugary foods we need to consume less of. It’s also starchy foods and high glycemic foods. What do I mean by that? The glycemic index refers to how a food impacts blood sugar. A high score means it greatly impacts blood sugar. Low means it has an only marginal impact. Anything that significantly raises blood sugar has the ability to create the health conditions above over time.

We can choose to stop consuming these foods, consume them less frequently, or consume much smaller portions to avoid and reverse these conditions. But the number one recommendation by numerous leading health professionals is choosing a low glycemic diet. (Exceptional article about the bad science behind current food guidelines.)

Thus, a low glycemic product is most important in a sugar substitute. That’s why honey, maple syrup, and raw sugar (even organic) are not my recommendation. You will see many nutritionists recommend these. However, the general adult public, who are at great risk of insulin resistance and metabolic syndrome, should not be consuming sweeteners that increase blood sugar, as these do, no matter how “natural” they are.

Artificial Sweeteners

A lot of people now realize that saccharin, aspartame, sucralose, and other artificial sweeteners may have health implications. They have been promoted as GRAS (generally regarded as safe) by the FDA and marketed to people with diabetes and those seeking weight loss. But the truth is, they may not be good for either. Decades after adding them to our food supply we are larger, with more diabetes, than ever. What gives?

Let’s take a deeper look at the safety and blood sugar impact of artificial sweeteners to understand this phenomenon.


Saccharin, the first artificial, zero-calorie sweetener, was accidentally discovered by two chemists in 1879. It’s 200-500 times as sweet as cane sugar and was promoted to diabetics and used in some drugs in place of sugar. Safety concerns emerged in the 1970’s after it was shown to cause bladder cancer in male rats, and in 1972 it was removed from the FDA’s GRAS list. In 1977 it was outright banned by the FDA, but congress intervened and permitted it to continue to be sold with the following warning:

“Use of this product may be hazardous to your health. This product contains saccharin which has been determined to cause cancer in laboratory animals.”

I don’t know about you, but I can’t help but wonder why congress felt it should override the role and decision of the FDA.

In 1981 saccharin was listed as an “anticipated human carcinogen” in the national Report on Carcinogens. In 1997 it was voted that it remain on that list by the National Toxicology Program’s advisory panel. (source)

Debate over the data continues today. On the saccharin site you will now see it is promoted as safe, well studied, and endorsed by the WHO. It has been allowed back in products in Canada since 2014.

The original study that found the cancer link can be found here. Studies exploring its link to human cancers can be found here. Other studies that link it to gut biome alterations and dysbiosis leading to intestinal damage, addiction behaviour, disturbed sleep cycles, weight gain, potential genotoxicity, wastewater contamination, and downregulation of tumour suppressor genes, among others, can be found here, on Green Med Info’s research database.

Saccharin is found in products like Sweet’n Low, the pink Equal, some diet sodas and candies, as well as in medications and lip balms today.


Studies on Aspartame (NutraSweet and the original Equal) link it to headaches and migraines in youth (source) and adults (source), neurotoxicity (brain damage)(source), oxidative stress (source), recurrent vulvar dermatoses (graphic content warning) (source), cancers (source), with serious withdrawal symptoms frequently reported clinically. Moreover, a 2018 report found that aspartame may cause weight gain and increase insulin resistance. More research on the safety concerns over aspartame can be found here.

Critics note that Aspartame breaks down into phenylalanine and aspartic acid in the brain, and breaks down into formaldehyde (highly toxic and carcinogenic) when heated.

Aspartame has also been linked to behavioural and cognitive problems. “Possible neurophysiological symptoms include learning problems, headache, seizure, migraines, irritable moods, anxiety, depression, and insomnia. The consumption of aspartame… can inhibit the synthesis and release of neurotransmitters, dopamine, norepinephrine, and serotonin, which are known regulators of neurophysiological activity.” (source)

It’s a zero calorie, non-nutritive sweetener used in diet food products. It’s 180-200 times sweeter than sugar and has been considered safe by the FDA and safe by Health Canada since 1981. It’s widely promoted as completely safe to consume, with bountiful studies to contradict all the studies above.

Acesulfame Potassium

You will find this non-nutritive zero calorie, artificial sweetener in a lot of products on our shelves today. It was accidentally discovered by scientists in 1967 and is about 200 times sweeter than sugar. Like saccharin it has a bitter aftertaste. Most often it’s blended with other sweeteners to mitigate that taste. It’s considered safe to cook with but degrades over time to a highly toxic substance. It’s found in candies, diet foods, protein shakes, dairy products, common food products in place of sugar, children’s products, and medications. It’s currently considered safe by the FDA and permissible by Health Canada.

Testing was done by Environment Canada from the Grand River to Lake Erie and acesulfame was found in high concentrations. The environmental effects of this are still not well understood (source).

Studies show acesulfame is present in breast milk after exposure (source), it’s been linked to urinary tract tumours (source), it’s associated with increased cancer risk (source), it stimulates insulin (source), can alter the gut biome (source), is associated with weight gain, obesity, and chronic inflammation (source), and brain damage when consumed early in life (source). For more data on the possible safety concerns of acesulfame, go here.


Sucralose (Splenda) is between 320-1000 times sweeter than sugar and twice as sweet as saccharin. It was discovered in 1976 and introduced to the US in 1999. It’s calorie-free, but contains carbs from the fillers in it. It does not have the bitter taste that other popular artificial sweeteners have.

While it’s promoted to be safe in cooking and is found in cooking products, there is evidence it breaks down at higher temperatures (>250F). There are concerns now that it may be unsafe to cook with due to this breakdown, which may raise cancer and other risk factors (source).

The powdered form is about 95% bulking agents (maltodextrin and dextrose) and they absolutely do impact insulin and blood sugar levels, although it’s promoted as safe for diabetics. “One small study in 17 people with severe obesity who didn’t regularly consume these sweeteners reported that sucralose elevated blood sugar levels by 14% and insulin levels by 20%.” (source)

You will find it in candy, breakfast bars, coffees, drinks, and diet products, often in combination with other sweeteners. It’s listed as safe by the FDA and Health Canada, and is endorsed by the WHO as safe for consumption.

Like acesulfame, sucralose has been found in breast milk (source). It has also been found to affect the glycemic and insulin responses in the body (source), to possibly cause liver damage (source), to be potentially carcinogenic and neurotoxic (brain damage) in rat studies (sources), and to alter the gut microbiome in a way that predisposes humans to health issues and may notbe reversible (source).

Further Research

Some of the research into the safety of artificial sweeteners is done on artificially sweetened product consumption, vs specific sweeteners. They are also often combined in food products, and none are studied in combination with others for their safety prior to approval. You can find more data like this by going to and searching the specific sweetener name or ‘artificial sweeteners.' I think people really want to be responsible for their food choices and empowered with more complete information to do that.

Next week we’ll do a deep dive into the more natural low calorie sweeteners on the market today to determine if any of them has less conflict surrounding their safety and less impact on blood sugar and insulin.

As always, if you have your own health issue or question, just send me an email at [email protected]. And if you’re looking for more specific health information check out my website at


Nonie Nutritionista