Sugar substitutes: Good or bad?

Low-calorie sweeteners and sugar alternatives are really popular with those who have a sweet tooth, want to lose weight or simply want to avoid sugar. But are they really less harmful than sugar?


Artificial sweetners

Artificial sweeteners such as saccharin, aspartame, Sucralose, acesulfame - Splenda, NutraSweet, SweetN’Low etc, health-harming effects have already been established for a few years now.  However, they are still ubiquitous (coffee shops, supermarket shelves, hidden in candy and chewing gum etc). Why is this is a problem?

Some of the ways artificial sweeteners can pose serious health risks are:

  • gut flora dysbiosis (increase of pathogenic bacteria and decrease of probiotics)
  • liver damage
  • carcinogenic effects
  • weight gain and cravings
  • visceral fat (around the belly)
  • raised insulin levels
  • digestive discomfort (bloating, gas, diarrhoea).

Why is a healthy microbiome so significant?

Importance of a healthy microbiome

Studies link artificial sweeteners to microbial imbalance (a disrupted ratio between probiotics and pathogens in our gut). A healthy gut flora is needed for a robust immune system, good mood (90% of neurotransmitters like serotonin and dopamine are secreted in the gut), optimal digestion and assimilation of food and micronutrients and production of certain nutrients. 

There is a misconception that since sweeteners do not contain calories, they do not affect blood glucose/ insulin levels and weight. Artificial sweeteners can actually lead tohigh blood sugar levels and even insulin resistance if consumption is chronic. If paired with a diet high in carbohydrates, or low in nutrients this can further lead to chronically high blood sugar levels, metabolic syndrome, pre-diabetes or even diabetes. There is hence no question that artificial sweeteners are not safe in diabetes. 

What sweeteners are safe?

Monk Fruit and Stevia are two natural sweeteners that have grown in popularity lately. 

Despite its very sweet taste, stevia is a calorie-free and carbohydrate-free sweetener that comes from a plant. Stevia has been discovered for quite a few years now, as well as been studied a lot, and is readily available in supermarkets and health food stores.

However, stevia rarely comes on its own. For that reason, it is important to learn to read food labels. Stevia is usually combined with maltitol (comes from corn) and erythritol that are known for their osmotic effects on the gut (bloating, gas, diarrhoea). Sometimes it is even mixed with sugar! On the other hand, pure unprocessed stevia has a unique metallic taste that many do not like. Unprocessed stevia is green rather than white, and comes in leave or powder form.

Stevia is asafer option than artificial sweeteners, as it doesn’t increase blood sugar and insulin levels, doesn’t affect the gut flora in a negative way and cannot cause weight gain on its own.

Is there a “but”?

Stevia is very sweet, meaning that once we consume it our brain thinks that energy is coming in the form of carbohydrates. So if we consume stevia in a drink, like coffee or tea, without any carb source our brain will be asking for the energy and the calories. Have you ever noticed that you have cravings for something sweet after you consume stevia?

Erythritol is the sweetener that stevia is mixed within more than 50% of products. Erythritol mimics the taste of sugar, does not affect blood glucose levels significantly and does not count as an artificial sweetener. It actually has been shown to have some benefits like protecting the teeth. 

Both stevia and erythritol are often used in ketogenic desserts and are mostly safe for diabetics. However, as described above, sugar alcohols, like erythritol and xylitol, not only can cause IBS-like symptoms but can also lead to headaches and migraines in sensitive people. It is hence important to identify the amount that one can tolerate, which differs from person to person. NB: Xylitol is very harmful for pets, and especially dogs, so be mindful of where you keep it!

What about monk fruit?

The latest natural sweetener that has occupied nutritionists and health advocates is monk fruit: a low-calorie sweetener that comes from a melon-like fruit mainly in China.

Like stevia, monk fruit has a very sweet taste (150-200 times more than sugar), with no calories or carbs, making it a great natural sweetener for keto diets and low-carb diets, and in diabetes.

One of the bestbenefits of monk fruit is its’ anti-inflammatory and immune-boosting properties and the high amount of antioxidants in contains.

Are there any downsides?

Like stevia, monk fruit should not be consumed without any carbohydrates, as it can increase cravings and appetite for something sweet. It should better be used in baked goods, in place of sugar, rather than in beverages. It as well, is difficult to find on its own and is usually mixed with erythritol, making it difficult to tolerate for people with sensitive guts. It is super important to check the ingredients before purchasing.

In addition, monk fruit goes through processing to improve its taste and is then homogenized and pasteurized. This means that the final product is not 100% ‘natural’.

Like other natural sweeteners, monk fruit does not raise blood sugar, making it safe for diabetics and weight loss. Interestingly enough, monk fruit not only doesn’t disrupt the delicate balance of the gut flora, but it also prevents the growth of bacterial pathogens and yeast in the digestive tract.

Of all natural, zero-carb sweeteners these are my two favourites, with a slight preference for monk fruit. Processing is minimal and blood sugar levels are not impacted. Stevia is more vastly available, but monk fruit is slowly gaining popularity! The taste of both is unique and not everyone likes them, especially stevia. Both are somewhat expensive but given their level of sweetness you only need to use a small amount. 

Bottom line:If you’re diabetic, have cancer, or are on a keto diet for a specific reason, or trying to lose weight, try the above natural sweeteners, after checking their labels. If you have no reason to avoid carbohydrates, a teaspoon of raw quality honey or organic maple syrup is not the end of the world!

Nutritionist Resource is not responsible for the articles published by members. The views expressed are those of the member who wrote the article.

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London W1G & NW1
Written by Olianna Gourli, Nutritional Therapist & Functional Medicine, Gut Specialist
London W1G & NW1

Olianna Gourli is a Naturopath, Nutritional Therapist & Functional Medicine Practitioner, with a background in science and research (UCL, IFM-USA). She has great expertise in weight management, gastrointestinal issues&IBS, hormonal imbalances & women's health, stress, sleep issues and chronic fatigue. She sees clients in London, Athens and online.

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