Not-so-sweet science

Hey there, time traveller!
This article was published 30/06/2023 (1171 days ago), so information in it may no longer be current.

(Casually sips Diet Coke)…

‘O-M-G, why are you drinking that, don’t you know it’s poison?”

The latest headlines are making their way through social media linking Splenda — a popular artificial sweetener — to DNA damage.

When studies like this come out, it’s important to keep three things in mind: what did it test, what did it find, and how does this apply in real life?

In this case, the study was performed in a lab, where one single marker of damage was slightly elevated. And Splenda wasn’t even tested — they examined one chemical compound that makes up one per cent of Splenda.

What they found in the lab wasn’t exactly a true representation of what is consumed in real life.

If you wanted to see the type of damage found in the experiment, you’d have to consume nearly 50,000 packets of Splenda or drink about 10,000 cans of diet soda. No one is doing that in a lifetime, let alone a year.

So, if you’re a soda lover you’re going back to full-sugar alternatives, right? You know what else has a mountain of evidence linking it to DNA damage? Real sugar consumed to excess! In one meta-analysis of over 25 studies, high glucose consumption was linked to DNA damage.

Why is the topic of sugar-free beverages so polarizing? That’s a good question. Maybe it’s the fact they have “artificial” in the name and are chemical-sounding in nature?

Hold your horses. Nearly everything is a chemical when broken down into its “raw” form. When you consume aspartame, the body breaks it down into aspartic acid and phenylalanine, amino acids found in most sources of protein. In fact, the amount of aspartic acid and phenylalanine found in food-based sources of protein far exceeds the amount found in aspartame.

Methanol tends to be the one that raises red flags, and yes, methanol can be harmful as it’s converted to formaldehyde in the body — a known carcinogen.

But the dose makes the poison, with the amount found in aspartame, too small to worry about. Methanol can be found in fruits and vegetables in higher concentrations.

Aspartame’s bad rap

In 2005, a study found more lymphomas and leukemias in rats fed very high doses of aspartame.

But, again, just like the Splenda study, the rats were given an absurdly large amount: between 4 mg/kg all the way up to 5,000 mg/kg of body weight.

That’s 10 cans of diet coke per day to a small rat, which relative to the weight of a human being would be up to 2,000 cans for us.

Health Canada has set the acceptable daily intake for aspartame at 40 mg/kg of body weight (20 cans for someone weighing 80 kg). That’s a huge amount I doubt anyone is getting close to (or they’d be bound to the bathroom all day long).

In 2002, Aspartame: Review of Safety was published in the monthly peer-reviewed scientific journal, Regulatory Toxicology and Pharmacology, concluding:

“A search of the scientific literature on the U.S. National Library of Medicine’s MEDLINE reveals almost 700 citations for aspartame with a number of these relevant to aspartame safety.

“The extensive body of research undertaken on aspartame clearly and overwhelmingly demonstrates its safety for its intended use.

“Further, aspartame has been approved for human consumption by regulatory agencies in more than 100 countries and received wide consumer acceptance with consumption by hundreds of millions of people over the past 20 years, representing billions of man-years of safe exposure.”

If aspartame was killing us, we’d know it by now.

Aspartame and weight gain

Some argue aspartame causes weight gain.

That’s technically impossible. It’s calorie-free at the amounts used in sugar-free beverages.

In one study, 41 overweight men and women were split into two groups. The group consuming the sucrose supplement — the one that contained calories — saw increases in calorie intake, body weight, fat mass and blood pressure; while these effects were not observed in a similar group of subjects who consumed artificial sweeteners.

So why do people think aspartame causes weight gain?

A 2017 meta-analysis of research on artificial sweeteners, published in the Canadian Medical Association Journal, found no clear evidence of weight-loss benefits for artificial sweeteners in randomized clinical trials, and reported studies associated artificial sweeteners with “increases in weight and waist circumference, and higher incidence of obesity, hypertension, metabolic syndrome, Type 2 diabetes and cardiovascular events.”

There are a few problems with this conclusion. Observational studies are limited because they don’t factor in overall lifestyle. People who drink diet drinks tend to fall for the “Health Halo Effect”: they assume because they’re drinking zero calories, they can eat more food.

We’ve all seen someone ordering a Diet Coke with a super-sized McDonald’s meal. People then make a faulty correlation between the two: “Diet drinks cause weight gain,” instead of, “It’s all the calories we consume apart from the drinks that cause weight gain.”

While there aren’t any studies supporting this, anecdotally, some of my clients have noted diet drinks tend to increase “sugar cravings” and break the seal, so to speak. If this happens to you, then you may need to look at alternatives.

One of the potential problems of artificial sweeteners is they may disrupt the balance of beneficial bacteria in your gut.

Scientists have found animals fed artificial sweeteners experience changes to their gut bacteria. However, it’s still not clear if or how artificial sweeteners might cause these changes, and what, if any, effects are experienced long-term. Gut health is an area science hasn’t fully grasped, but things are progressing in this area.

A study recently found people who drank one artificially sweetened drink per day had up to three times the risk of stroke and dementia.

Pouring cold water on this theory, the researchers themselves looked at this link over the long term and when other risk factors for stroke and dementia (like Type 2 diabetes) were accounted for, the link between artificial sweeteners and stroke and dementia was statistically insignificant.

Take-home points

1. There are more than 200 studies that show aspartame is safe for human consumption.

2. Unless you’re a rat, or guzzle 20-plus diet drinks per day, you have nothing to worry about in moderation.

3. If you have the extremely rare genetic disorder phenylketonuria then you should avoid aspartame. You would know this already.

4. There is some emerging research suggesting artificial sweeteners can have a negative impact on the gut microbiome. This is still up for debate and the alternative to these beverages is also shown to do the same (as in, too much sugar can reduce beneficial bacteria leading to a leaky gut syndrome).

5. In a perfect world, you’d only drink plain water, but human beings like their flavour and this is one way to get it without consuming a pile of calories. If a diet drink helps you reduce night-time snacking and you don’t experience any of the aforementioned side effects, have at it.

Mitch Calvert is a Winnipeg-based fitness coach who has helped more than 1,500 people transform their lives over the past decade. Visit mitchcalvert.com to grab a free copy of his metabolism jumpstart or drop him a message at mitch@mitchcalvert.com.