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Why Stevia is Bad for You: Liver, Kidney, Gut, Immune and Blood Health is an updated post that shares why I now believe stevia to be bad for everyone, no matter how it’s used, whereas formerly I considered it safe if used in certain ways.
Since using it years ago, I’ve now been shown studies that specifically isolate the damage done to the liver and kidneys; so we are no longer speculating about why stevia might be damaging to one’s health.
Stevia is all the more dangerous because it does not cause immediate symptoms for most people. Instead its insidious behavior affects the long term health of organs and gut health.
Why stevia is bad for you: What body systems it affects
As one study says of artificial sweeteners, stevia included:
The human body responds to these sweeteners in a very complex way. The sweetness of non-nutritive sweeteners is more potent than that of sucrose or high-fructose corn syrup.
This study evaluated the effect of stevia on feeding behavior, blood biochemical parameters, enzyme activities and immunological parameters in mice, compared to sucrose.
At both 8 and 16 weeks, data was gathered in several categories with the following findings:
- Stevia administrated mice groups showed a reduction in water consumption when stevia was not added.
- Type 2 Diabetes biomarkers increased significantly in mice who drank stevia water, versus control groups.
- Free radicals and nitric oxide levels were elevated after stevia consumption.
- Long term administration of stevia significantly increased cholesterol levels and significantly decreased HDL levels (serum high-density lipoproteins) and increased LDL levels (serum low-density lipoproteins). Levels of free fatty acids were significantly higher than those of control groups.
Regarding blood biochemistry, the results were pronounced:
- Stevia administration caused a significant reduction in hemoglobin and hematocrit levels, and RBCs (red blood cells) count, compared to control groups.
- In female mice, stevia showed a significant decrease in WBCs (white blood cells) count.
In reference to liver health, the results were again extreme:
- Stevia administration increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. (AST and ALT are two of the liver enzymes doctors look at when trying to figure out if you have a problem with your liver.)
- Levels of liver triglycerides and cholesterol in male mice groups increased.
- Stevia significantly elevated liver cholesterol levels in both male and female mice groups.
The results for kidney health were also condemning:
- Stevia affected urea levels, but more so in male subjects, whereas creatinine levels were more elevated in female subjects. (The former can indicate kidney injury or disease in lab testing, whereas the latter indicates kidney problems, oftentimes a blocked urinary tract.)
- Damage to the kidneys upon dissection (and studies of the samples) showed congested blood vessels after 16 weeks of administration.
In addition to all these somewhat shocking results, stevia, the longer it was administered also affected:
- gut integrity and microbiome behavior
- the immune system, with increased IgG, IgE and IgA levels, all pointing to an increased likelihood of allergies, chronic infections and autoimmunity
- inflammation, with a significant increase in pro-inflammatory cytokines
What happens to stevia in the body
One of my favorite aspects of this study was the window it provided into what happens to stevia in the body and why it affects the liver and kidneys adversely.
Stevia is not absorbed in the intestine. Instead, the body converts stevioside into steviol (or stores it as stevioside). Steviol has the highest accumulation in the liver.
The body then tries to get rid of it via bile, but the removal and excretion of steviol by the liver negatively affects the bile metabolism. Chronic stevia consumption puts stress on the liver that results in an elevation of liver enzymes and altered bile output!
Stevia even elevates the level of liver fat.
Regarding the kidneys, this study calls steviol, “a toxic stevioside metabolite” and says it is:
… reabsorbed from the intestine to the blood circulation and accumulated in the kidney to be excreted in urine. The body begins to step up urination to facilitate its removal; a process known as diuresis.
This study adds that the proximal tubules were the site for stevioside accumulation. This, significantly, is the site of elimination for xenobiotics (drugs, food additives and environmental pollutants)! Any disturbance in this system reduces the body’s ability to detox xenobiotics!
And, how noteworthy, that the body puts stevia where it puts poisons!
My former beliefs about stevia
In case it’s helpful, how I used to eat stevia was to combine it and a totally natural sweetener, with the goal of circumventing what is sometimes called glucose confusion (which used to be my main concern). Here’s that concept as I once explained it:
‘My favorite concern about stevia is that the sweet taste on one’s tongue not followed by the expected ingestion of glucose can cause an insulin confusion. I love the idea that our sense of taste is connected to our body’s preparatory action!…
I like to combine stevia with one other sweetener. In a cup of tea, for instance, I put a bit of honey and a bit of stevia. I do this in baked goods, too, and often in my cookbook. This allows me to use less of the sweetener that I’m trying to limit, in this case honey, but to still achieve the level of sweetness that I prefer. My body is not faked out. It does receive glucose after tasting sweet.
I ran this method by my doctor who is very familiar with the insulin confusion that applies to artificial sweeteners. He felt it a good and safe solution.’
My updated view on stevia
As outlined above in the main article, I now believe the newer evidence outweighs the earlier guessing or incomplete studies on this topic.
For those who own my cookbook, I now think it’s safer to just omit the stevia, or use a natural sweetener, like honey, alone. Personally, I believe it’s better to save sweets for truly special occasions.
Most days, I do not sweeten any of my food. Even waffles and porridge, I just add a small amount of coconut oil (for the waffle) or non-dairy milk (for the porridge) + sea salt. No sweetener. It’s delicious and very satisfying.
Why I stopped using stevia
I didn’t know about the studies I share in this article when I stopped using stevia.
Instead, I stopped using it for two reasons: my current doctor advised against it. And, I no longer wanted to cultivate the need for something sweet.
About fifteen years ago, I was addicted to sugar. Stevia helped me to overcome that, but brought new evils into my body, without me knowing it.
Sometime in the last five years, I began to more fully understand that sweets in general are not good for the liver or one’s overall health. I still really enjoy not-too-sweet of treats, but only very occasionally.
Giving up stevia was me admitting that it was doing unseen harm, and that I didn’t want to sweeten so many of my foods any longer.
Other possible concerns about stevia
- Stevia is linked by some native cultures with infertility. Historically it was even used in South America as a contraceptive. However, the studies that support this view have mixed findings. (1, 2) It may be wise to avoid stevia if you’re trying to conceive, especially if infertility is an issue.
- Knowing stevia harms multiple organs and the gut microbiome is, of course, enough reason to avoid it, especially while trying to conceive.
- With thyroid health in mind, stevia should not be used to get a sweet taste without any carbs. Specifically, our thyroid is taxed if we don’t have enough insulin. Insulin is what helps convert inactive T4 to active T3. (source) Insulin levels are usually low in those with low-carb diets.
- We may endanger ourselves and our thyroid health by maintaining a low-carb diet long term. I got both Hashimoto’s and adrenal fatigue (or HPA axis dysfunction) after years of a low carb diet with stevia.
- The main hormone that gets dysregulated in adrenal fatigue is cortisol, and cortisol has been shown to increase on a low carb diet. This means that a low carb diet is a potential adrenal stressor in susceptible individuals. (source)
Conclusion: Why Stevia is Bad for You
Through several studies in recent years, we can conclude that stevia has a variety of harmful effects. While not every person will feel all of these effects, they were indeed observed in lab rats consistently.
- ‘s sweet taste causes addiction.
- causes insulin resistance.
- changes the gut microbiome.
- significantly elevated levels of liver function enzymes, urea, creatinine, cholesterol, LDL and free fatty acids.
- leads to oxidative stress (as seen by the elevated level of NO and the reduced level of antioxidants).
- causes inflammation in both the liver and kidneys.
- affects digestion and liver function.
- contributes to allergies, leaky gut, autoimmunity and overall inflammation.