The use of artificial sweeteners is widespread in a lot of ‘low energy’ or ‘low sugar’ foods and beverages, and their use in recent years has increased with the general shift by many people towards low carbohydrate/low sugar dietary patterns.  

But what impact can these substances have on female reproductive and hormonal health, fertility and pregnancy?

What are artificial sweeteners?

First, we need be clear about what artificial sweeteners actually are.

They are a low-calorie sugar replacement mainly used in foods/drinks, with common ones being acesulphame potassium, advantame, alitame, aspartame, aspartame-acesulphame salt, cyclamate, neotame, saccharin, sucralose, thaumatin and sugar alcohols.

How can artificial sweeteners affect female reproductive health and fertility?

Currently, evidence regarding the impact of artificial sweeteners on female reproductive and hormonal health, fertility and pregnancy points to a cause for concern with their use, with animal studies showing the following effects:  

(NB: a note about animal studies – effects observed in animal studies are not confirmation that the same effects will definitely occur in humans, but they can provide potential mechanisms that they may occur in humans, requiring further study in humans to confirm such effects).   

• abnormal/irregular menstrual cycles
• progesterone level imbalances
• reduced oocyte quality
• increased oxidative stress in the endometrium.

The impact of artificial sweeteners on the embryo/foetus (also seen in animal studies) include:

• increased chromosomal abnormalities
• reduced embryo size
• decreased embryo development scores.

Human studies have also observed that females who regularly consumed artificial sweeteners had heavier menstrual bleeds and more abdominal pain during the menstrual phase.

Artificial sweeteners also negatively influenced the health (quality and morphology) of oocytes, embryos and the chance of blastocyst formation, implantation and pregnancy occurring when 2-3 servings/day or more were consumed.

And men did not get off unscathed, with effects on sperm including an increased rate of DNA fragmentation (breaking of DNA into pieces which significantly influences sperm quality) and more sperm undergoing apoptosis (cell death).

Put another way, artificial sweetener intake, especially when several serves a day are consumed regularly, may reduce the quality of both sperm and oocytes, which significantly influences the capacity of a couple to conceive.

It should also be noted that there is also a distinct lack of evidence confirming the definitive safety of artificial sweetener consumption for healthy fertility, reproductive and pregnancy outcomes.

What can I do about?

So, should you do if you are experiencing reproductive imbalances and/or fertility difficulties and you regularly consume artificial sweeteners?

Some suggestions to consider:

1. Knowledge is power, so record for 1-2 weeks how many servings per day/week of artificial sweeteners you eat or drink so you know how much you regularly consume.
2. Note any patterns regarding a particular time of day or week you are consuming foods/drinks with artificial sweeteners, and if there are any specific triggers (e.g. people/places/emotions/boredom).
3. Read ingredient lists closely for any of the names mentioned above and consider using an alternative option without these ingredients.
4. The less highly processed a food/drink is the less likelihood it will contain artificial sweeteners, so look at what types of foods or drinks you are consuming the most each day/week and substitute with a less processed alternative.
5. Drink more water and add fruit like lemons, limes, berries, oranges or herbs like mint or basil.
6. If significant sugar cravings are driving your intake, this may be a sign of imbalances of:  
   1. Female reproductive hormones (oestrogen, progesterone)
   1. Blood sugar regulating hormones (insulin)
   1. Stress hormones (cortisol) from chronic stress
   1. Gut bacteria in the large and/or small intestines
   1. Nutritional insufficiencies or deficiencies such as magnesium, chromium and/or zinc.

If any of these sound like they could be you, seeking the advice of a health professional is worth considering to investigate and treat any potential imbalances.

(References available on request).