Don't Use Splenda for Weight Loss

Many people who want to lose weight, for the new year or for other reasons, switch sugar for artificial sweeteners to reduce energy consumption. However, many also do not know of the multitude of research papers uncovering the harmful effects of these sweeteners. Recently there has been a new addition to this multitude, a new study examining the effects of Splenda (sucralose) on the thyroid function and metabolism of mammals.

All of this may be a big surprise to those new to the world of natural health. Advertisements frequently pressure parents to use artificial sweeteners in cooking to keep their children healthy, and often depict scenes such as mothers baking while holding a young child. But it looks increasingly likely that the reality is that these sweeteners actually promote weight gain, rather than prevent it!

Sucralose. Source: Rob Hooft

In this new study, 105 Sprague-Dawley rats were divided into three groups: one without sugar, one with 10 grams of sucrose and a third with enough sucralose to create the same level of sweetness as the second diet. All of these had the same energy content. While sugar stimulates thyroid hormone production, the diet containing sucralose led to a suppression of thyroid peroxidase (TPO), T4 and T3 production. Sucralose seemed to interfere with normal pituitary-thyroid axis function, as it did not only reduce TPO but also TSH - thyroid stimulating hormone. While overall levels of T4 and T3 decreased, levels of the free hormones increased, in an attempt to counteract the effects of sucralose. This means that you may not notice the harmful effects of artificial sweeteners right away, even when they are damaging your body, because of the regulatory mechanisms that keep the blood normal and healthy. Sucralose also increased appetite and weight gain, exactly what people are trying to avoid by consuming artificial sweeteners! Part of this is because the thyroid hormones help with keeping the metabolic fires burning, too little leads to a slower metabolism and therefore weight gain. On the other hand, those with hyperthyroidism suffer from weight loss if untreated, but do not damage yourself with artificial sweeteners if your thyroid is overactive! To make things even worse, it was also found that sucralose negatively affected gut bacteria and its epithelial border function. This may lead to poor digestion or inflammation.

While skeptics would try to invalidate this study because rats were used instead of humans, the authors stated that it has already been demonstrated that T4 levels in rodents are a valid indication of thyroid function in humans. There is also the fact that poisoning humans is completely unethical. And if you do want human studies, one on 17 obese people showed that sucralose consumption negatively affects blood glucose and insulin levels. Therefore, long-term consumption may contribute to diabetes or insulin resistance, and this on top of any effects on thyroid function could be disastrous to your health. Overall, it's best to just reduce added sugar consumption, and eat fruit or small amounts of honey or stevia instead of toxic chemicals.