Issue no. 1: The impact of artificial sweeteners on your health

🔥🔥 Hot off the press: did you say weight gain?

While most people took advantage of the school holidays to relax, scientific researchers continued to work hard in August!

An article was published in Medical Press last month with a catchy headline 👇

But, but, but…. before you go spreading the word that drinking diet soda will make you gain weight, it's important to note that the headline can be misleading!

1. The word "links" in the headline indicates that it is impossible to determine cause and effect. The researchers cannot say for certain that artificial sweeteners cause increased fat mass. They only found an association between the two. It's possible that increased fat mass causes people to consume more artificial sweeteners, or vice versa.

2. The headline also uses the plural "artificial sweeteners". This may lead you to believe that all artificial sweeteners were studied, but this is not the case.

🔎 In depth: What did the actual research says?

Now, let's take a closer look at the scientific study published in Nature 👇

🎯 Right away, we can see that only aspartame and saccharin were studied. The news article made it seem like all artificial sweeteners were examined, but that is not the case!

In fact, the research only looked at two out of the eight most common artificial sweeteners: acesulfame potassium, advantame, aspartame, neotame, saccharin, sucralose, luo han guo, and purified stevia leaf extracts.

The study is sound (scientifically speaking!). Researchers surveyed the participants' habitual diets and took body measurements of the same 3,088 men and women at the start of the study, 7 years later, and again 13 years after that.

They found that higher intakes of aspartame and saccharin were associated with increased fat mass around the organs, in the muscles, and under the skin. This essentially meant greater body weight and waist circumference. 

And since most diet beverages (i.e., sugar-free beverages with sweeteners) contain aspartame and saccharin, it's no surprise that diet beverages were found to have the same association as aspartame and saccharin.

The most interesting part is: that diet beverages, as well as aspartame and saccharin, were associated with an increased risk of obesity over a 25-year period. But again, no cause and effect could be determined!

*Graph from original article https://doi.org/10.1038/s41366-023-01336-y. Labels and commentary added to simplify understanding.

This study is powerful because researchers looked at habitual intakes. They did not promote the intake of artificial sweeteners, but rather captured the real-world consumption in adults (between 0 to 2.33 servings per day). How many people do you know who drink more than two cans of diet drinks per day?

But this is not the first study to report these results. Other studies have also found similar associations between artificial sweetener intake and increased fat mass. And animal studies have demonstrated a causal relationship between artificial sweetener intake and fat accumulation.

Some studies have found different results, but many of these studies were short-term and looked at the effects of using artificial sweeteners in conjunction with weight loss programs. As a result, they may not accurately reflect the usual consumption of artificial sweeteners.

🥤🥤Why are some sweeteners associated with greater fat mass?

The authors did not study the underlying mechanisms, and it is not easy to do this in humans for ethical reasons. However, there are some hypotheses:

• Artificial sweeteners promote appetite and hunger levels in animal studies

• Saccharin promotes fat accumulation and inhibits fat breakdown in laboratory studies 

• Aspartame may suppress the activity of enzymes in the intestine, promoting inflammation in animal studies 

• Artificial sweeteners alter the gut microbiome, resulting in changes in blood sugar levels in response to eating sugar in human studies

In short… we are still trying to figure out the long-term effects of artificial sweeteners on our health. However, the evidence so far does not favour artificial sweeteners.

🤔🤔What does this mean for you?

Manufacturers replaced sugar with artificial sweeteners to reduce calories and the amount of sugar in food and drinks. However, this focus on calories overlooked an important aspect: our metabolism, or the effect that artificial sweeteners have on our bodies (who would have thought!?).

Our gut is not equipped to break down sweeteners.While simple sugars (e.g., white sugar) has calories and spikes blood sugar levels, it is the simplest nutrient to digest and use. Artificial sweeteners, on the other hand, are man-made substances that….can’t be absorbed and have no use in our bodies.

Researchers have called for national recommendations to be changed in response to emerging research on the potential harmful effects of artificial sweeteners in diet beverages. However, this will take time 💨💨

Occasional consumption is fine if you enjoy the taste or if it’s the most sensible choice at the pub 🍺🍺, but habitual consumption is best avoided.

But why not opting for homemade drinks? such as teas, iced teas, fruit-infused water, or lemonades. These are all better options for hydration. And of course, water is always king!

And finally!

Let’s remember some crazy reasons why people like diet beverages!

To your health!

Paolo

Did you enjoy this newsletter or know someone who has to read it?

Original study

Steffen, B.T., Jacobs, D.R., Yi, SY. et al. Long-term aspartame and saccharin intakes are related to greater volumes of visceral, intermuscular, and subcutaneous adipose tissue: the CARDIA study. Int J Obes (2023). https://doi.org/10.1038/s41366-023-01336-y