Are Artificial Sweeteners Causing Your Thyroid Issues?

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You think you are making a healthy choice by reaching for the pink, yellow, or blue packets of artificial sweeteners instead of sugar, right? Or you substitute a diet soft drink for the sugar-laden real thing, feeling like it's a good decision. But is it? As a thyroid patient, should you be using artificial sweeteners? Let's take a look at this issue and the impact on your health.


About artificial sweeteners

Artificial sweeteners — also known as non-nutritive sweeteners — are chemically manufactured, non-caloric sweeteners designed to replace actual sugar in drinks and foods. The three most popular artificial sweeteners include:

  • Aspartame: the “blue packets,” marketed as Equal and NutraSweet

  • Sucralose: the “yellow packets,” marketed as Splenda

  • Saccharin: the “pink packets,” marketed as Sweet ‘n Low

Artificial sweeteners are used to control sugar intake primarily for weight loss.


Risks of artificial sweeteners

Aspartame has been linked to neurological problems including dizziness, headaches, and seizures, and increased risks of Parkinson's and Alzheimer's diseases. Sucralose has been associated with negative changes in gut bacteria, which can affect immunity and contribute to autoimmune disease risk. Saccharin has been associated with potential cancer risks.

The Center for Science in the Public Interest (CSPI) recommends caution with sucralose and saccharin, and recommends avoiding aspartame.


The link to Hashimoto's disease

Research reported on at the 2015 International Thyroid Congress found that artificial sweetener use is linked to the development of Hashimoto’s disease, the autoimmune disease that frequently causes hypothyroidism.

The research also found that the use of artificial sweeteners — especially aspartame and sucralose —specifically correlated to increased levels of thyroid stimulating hormone (TSH). Elevated TSH levels are a sign of hypothyroidism.


Risk of Hashimoto's and hypothyroidism

The 2015 research found that consuming even three to four packets of sweetener a day was associated with a significantly higher risk of Hashimoto’s and hypothyroidism. These findings were so dramatic that the researchers advised thyroid patients to avoid the use of artificial sweeteners.

A study published in the European Journal of Nutrition found that artificial sweeteners reduce the synthesis of thyroid hormones and lower T3 levels, factors associated with hypothyroidism.


Reversing Hashimoto's and hypothyroidism

In the research study, some of the study subjects stopped using artificial sweeteners. A surprising two-thirds of those who stopped using the sweeteners had a total reversal of their Hashimoto’s disease. Thyroid antibodies dropped and returned to normal, TSH fell, and most of the patients were able to stop taking thyroid hormone replacement medication.


Aspartame and Graves' disease

There is some evidence, including the accounts of hundreds of thyroid patients, linking aspartame to the onset of Graves’ disease. Nutritionist Dr. Janet Hull traced the onset of her own Graves’ disease to aspartame and wrote about it in her book, “Sweet Poison.” At her website, Dr. Hull has reported on numerous cases of artificial sweetener-related illnesses, including thyroid problems.


Artificial sweeteners change your microbiome

Research also shows that artificial sweeteners can change the bacteria balance in your stomach and intestines, known as the "gut microbiome." Since your gut microbiome is an essential part of your immune system, an imbalance can contribute to the risk of autoimmune disease. One study in the Journal of Toxicology and Environmental Health found that the sweeteners reduced the level of good bacteria by half.


Artificial sweeteners don't help you lose weight

The latest research has found that artificial sweeteners do not help with weight loss or maintenance. They have the opposite effect, causing weight gain and making it more difficult to lose weight. A study published in the Canadian Medical Association Journal found that artificial sweeteners increased the risk for weight gain, obesity, diabetes, and heart disease.


Artificial sweeteners are linked to glucose intolerance

There is some evidence that over time, use of artificial sweeteners impairs your ability to metabolize and process actual sugar. This makes you less effective at burning calories from all sources, and can contribute to increased weight gain and glucose intolerance.


What about stevia?

Stevia is a sweetener derived from a plant. Some forms that are marketed are, therefore, not considered "artificial." (Note, however, that the "Truvia" form of stevia has been chemically processed.) While there is little evidence that stevia is associated with increased risk of autoimmunity or other diseases, it still poses the same issues regarding weight gain and other risks of artificial sweeteners.