Teaser Excerpt from The Paleo Approach: The Trouble with Stevia
March 11, 2013 in Baking Ingredients, Is It Paleo?, Sugar/Carbs, The Paleo Approach Excerpts
I get often get asked why I do not endorse the consumption of stevia (see my post Is Sugar Paleo? for more information on what sugars/sweeteners I do endorse). So, as I found myself including a section on the trouble with stevia for The Paleo Approach, I felt like this was a good topic to include as a book teaser on the blog. I have a section of Chapter 3 that describes the role that sugars, blood sugar regulation, insulin sensitivity, fructose, sugar alcohols and nonnutritive sweeteners play in propagating inflammation in autoimmune disease. This excerpt is included as a standalone text box following the subsection on nonnutritive sweeteners.
This excerpt is from Chapter 3 (The Diet Link to Autoimmune Disease chapter).
Stevia is often recommended as a natural sugar substitute because it comes from the leaf of a plant (Stevia rebaudiana Bertoni). It tastes sweet on the tongue, requires very small quantities to sweeten baking, and contains no sugar. While some experts advise caution against purified and manufactured forms of stevia, green leaf stevia is typically endorsed. On the surface, it sounds like a perfect solution. However, I do not recommend the consumption of stevia, even in its most natural form. The chemicals responsible for the sweet taste of stevia are called steviol glycosides (there are at least ten different steviol glycosides present in the stevia plant). Purified/manufactured forms of stevia often isolate one or two of these steviol glycosides whereas green leaf stevia (which is simply the dried and powdered leaves of the stevia plant) contain all ten.
Steviol glycosides are synthesized in the same pathway and end up being structurally very similar to the plant hormones gibberellin and kaurene. This means that steviol glycosides have a hormone structure. The majority of toxicological studies establish that stevia is safe, however there are some studies showing that it can act as a mutagen and may increase the risk of cancer (these studies are in the minority and tend to use quite high concentrations, so they are readily discarded in discussions of the overall safety of consuming stevia). Whether or not stevia causes genetic mutations is not the only cause for concern, however (even if safety studies focus on this particular property). For those with autoimmune disease, in which hormones have such a dramatic impact on disease development and progression, the impact of consuming stevia on hormone regulation is relevant.
There is evidence that steviol glycosides have contraceptive effects in both males and females. In particular, one specific steviol glycoside, called stevioside, has been shown to have potent contraceptive properties in female rats, implying that stevia may have an impact on estrogen, progesterone or both. In another study, male rats fed stevia extracts showed a decrease in fertility, reduced testosterone levels and testicular atrophy, potentially attributable binding of steviol glycosides with an androgen receptor. Although no studies have been conducted evaluating the impact of stevia on fertility in humans, the stevia plant was traditionally used to control the fertility of women by the Guarani Indians in southern Brazil. While small and occasional consumption of stevia likely has little to no impact on general health, it should not be consumed on a regular basis especially by those with altered hormone balance and dysfunctional immune systems.
Brusick DJ. A critical review of the genetic toxicity of steviol and steviol glycosides. Food Chem Toxicol. 2008 Jul;46 Suppl 7:S83-91.
Mazzei Planas G and Kuć J. Contraceptive properties of Stevia rebaudiana. Science. 1968 Nov 29;162(3857):1007.
Melis MS Effects of chronic administration of Stevia rebaudiana on fertility in rats Journal of Ethnopharmacology 1999 Nov 67(2):157–161
Melis MS. Chronic administration of aqueous extract of Stevia rebaudiana in rats: renal effects. Journal of Ethnopharmacology 1995. July 47(3):129–134
Oliveira-Filho RM et al. Chronic administration of aqueous extract of Stevia rebaudiana (Bert.) Bertoni in rats: Endocrine effects. General Pharmacology: The Vascular System. 1989. 20(2):187–191
I’ve been looking on the green pasture website and they are out of oslo orange fermented cod liver oil. Would you suggest to get the unflavoured rather than the cinnamon tingle since it has stevia in it? It’s not cheap so I want to make sure I’m getting what’s best to help my autoimmune diseases and not make them worse.
I actually just bought the unflavored for the same reason. I haven’t tried it yet, so I don’t know how good/bad it is.
Thanks for letting me know
Thank you for this post!! Looking forward to reading more in your book.
Darn! I probably use 4 dropperfulls of sweetleaf stevia in my tea. I became hooked on it when I made the poor decision to do several HCG protocols. My hormones became disregulated, especially progesterone and I started having polycystic ovaries something I never had experienced before. I will never know what caused the hormone disregulation but now I guess I can add the stevia as a possible cause along with the HCG.
Awesome research. This is definitely new stuff people need to learn.
Very excited about your book. Will there be a kindle edition?
Of course!
Very good article. It unfortunately is very frustrating as well. I use stevia to sweeten Kefir for my family and our kefir smoothies. I also use it in a gelatin,lemon treat. Without the sweetness, most of my family would not eat these healing foods. We all have health issues that adding the hormonal issues stevia could be causing isn’t good. I use raw honey to sweeten warm/hot beverages when needed or when I am making gelatin jigglers or “gummy” treats but honey doesn’t work well for cold items. I guess I am on the hunt for a healthy sweetener again. Thanks for posting this great info.
You just blew my mind, Sara. As someone trying to conceive and having issues, this is timely info for me. I am flabbergasted that I’ve never heard a thing about this before. I realize it’s not necessarily conclusive, but it’s enough for me to be concerned and skip it. Please let us know how it goes with the unflavored FCLO. I’ve been using cinnamon tingle. Thank you for sharing this info in advance of your book release. You are doing incredible work!
Hi Sarah. Interestingly, I was just reading about this yesterday. What do you think about this article. It seems to indicate that the fertility and hormonal issues concerning stevia are a non issue. http://natural-fertility-info.com/does-stevia-cause-infertility.html
So, I went back to the literature. What I found was more studies showing it has an effect on male and female fertility and probably the same number of studies showing it has no effect. I guess I would say the jury is still out–but there is sufficient evidence to warrant careful thought before consuming it (and I will continue to choose not to).
Hi Sarah, I’m also concerned about the stevia content in the flavored Royal Ice FCLO/BO blends… is that tsp or so a day worth a fertility concern? Also, is the connection purely a fertility issue or would it possible disrupt hormones in post-menopausal women? (Asking cause my mom’s a HUGE stevia user)
Yeah, I think it’s a shame that Green Pasture’s only sweetener is stevia (I wish they had a honey option or something similar). I personally take either oslo orange or unflavored (yuck) FCLO (I don’t to the BO blends because I have an autoimmune disease). I know my hormones are still a little off so I’m really mindful about what I eat or what is in my environment that might be stopping them from normalizing. BUT, I did just buy the licorice flavored emulsified FCLO for my kids to try and it does contain stevia. I’m also conflicted between giving them a (albeit small) daily dose of stevia but then getting all those other great vitamins into them. Anyway, we’re trying it and I can already see the dark circles under my oldest’s eyes disappear, so I think great vitamins is winning out. As for post-menopausal women, the studies in male mice indicated that the effect was probably due to binding with an androgen receptor, which would mean stevia would disrupt hormones in anyone. It’s unclear how much you need to take though for that to be a problem (and there are certainly studies showing no effect on fertility just to muddy the waters a little). But, I can tell you that even if I was post-menopausal, I would not be choosing stevia (although, just as I do now, I don’t fret over having a little once in a while).
Can you clarify on avoiding BO with AI? Is it because of dairy? Or is there something else I’m missing. I apologize, I tried to do a search, and couldn’t come back with much. Getting ready to order BO because of all of its benefits but I also have an AI disease (although dairy hasn’t proven to be a trigger), and don’t want to do something totally stupid.
Yes, it’s because of the dairy. If you tolerate dairy, it’s an awesome supplement, but even trace dairy proteins can be a problem for many with autoimmune disease.
Well, they fed the mice a lot more stevia than a normal person would ever ingest. That’s the point of it, that you don’t need much at all to get the desired sweetness.
One of the first users of stevia here in Norway, a man in his forties, have used it each and every day in huge amounts in everything for more than 10 years. He has 8 children… I know women who have beem using stevia for 20 years without any adverse effects what so ever.
I use stevia in my green tea and coffee. I cannot drink either without sweetening it. What would you suggest, knowing we are fitness people who maintain a lower level of bodyfat and don’t want to mess with out insulin levels too much?
I guess it depends on how sweet you like your beverages. Generally, I would suggest either an unrefined granulated sugar or honey (molasses is awesome in coffee too and has a pretty good mineral content) while also working to gradually decrease the amount you add. Also, adding a quality fat to coffee can really take away the need for sugar completely. My favourite is the Bulletproof Exec method of blending 1Tbsp grass-fed unsealed butter and 1Tbsp coconut oil per 8 oz cup of coffee (about 20 seconds in the blender). It’s delicious! Cinnamon can also trick your taste buds into thinking its sweeter than it is. There’s also always the option of finding something else to drink that you don’t feel the need to sweeten.
Will the granulated sugar mess with insulin though? I would think so. I know coffee and green tea are very healthy drinks with tons of research on them, so I don’t want to give either up, but can’t imagine ever drinking them black with nothing to sweeten the taste a bit.
Thanks!
These aren’t magical elixirs. Vegetables and fruit are also great sources of polyphenols and flavonoids. If you don’t like the without sugar, there’s no good reason to drink them. And in fact, many of us in the paleo community are taking steps away from coffee. http://www.thepaleomom.com/2012/07/pros-and-cons-of-coffee.html
Yikes!! I put NOW FOODS Stevia in my Matcha tea every day!!!! I used stevia because it is zero-carbs and not a horrendous gassy farty laxtive (like most low carb polyols)!! I did hear about it being a natural contraceptive before! But though that cant be bad right?!! If it lowered testosterone in the male rats, what did it do to the female ones?? Is there anything sweet tasting on earth that has no carbs and wont mess up the body?!! eeek!
No. There is no way to cheat sweet. Sadly.
I will have to retrain my brain into not registering any emotion of pleasure for (zero carb) sweet tastes LOL!!!
Interesting…What are your thoughts on erythritol and oligosaccharides (I use Swerve Sweetener)?
Erythritol has been shown to increase epithelial permeability in cell culture studies through an effect on the tight junctions… meaning it has the capacity to cause a leaky gut.
Well, it looks like a case of omit sugar entirely except naturally occurring in foods or ‘pick your poison’.
Stevia is the recommended sweetener for those with diabetes, according to Dr.R Bernstein, ‘Diabetes Solution’. You do need to check the powdered version for maltodextrin; stevia liquid contains no sugars of any kind and only minute amounts of carb. Weighing the pros and cons many result in a different conclusion depending on your age and health.
Hi there. I am wondering if you were able to read the contents of the studies you cite. I tried to find the information to look at the studies more closely and all of them were not published in entirety on the internet, but instead you needed to pay $31.50 to read each study. Did you perhaps pay for the studies to see how they were conducted? And if not, could you please direct me to where I can read more information about the studies so I can better evaluate this information? Thanks so much in advance.
I do (my husband is a university professor and can usually access articles for me) and I have read both studies showing effects and the studies showing no effects. It is not a good idea to dismiss a study simply because it is performed at high doses (although you might want to dismiss studies that give stevia by injection compared to orally). This is typical in scientific research, in part because rodents are usually more resilient than humans, and in part because this is how you see clearly measurable effects. For human consumption, this means that consuming stevia is unlikely to make you sterile the way it does in high doses in rodents, but it does give a strong indication that there could be an effect on your gonadotrophins. Maybe in humans it is a 5% or or even 1% difference at the amounts that most people who consume stevia frequently would get. For plenty of people, this might not be noticeable, but for those with autoimmune disease, who already tend to have issues with hormone regulation, I think anything with this type of an potential effect should be avoided. That being said, there is certainly no consensus in the scientific literature as to the effects of stevia on reproductive hormones.
Hi again, Sarah. I did some more poking around and this post seems to show that there are major problems with the fertility studies in rats. The scientist who published the study even admits that there were problems. This part of the post is quite interesting from a study in 1999 on primates:
“n 1999, the primate research center of Chulalonhkorn University in Bangkok, Thailand gave high doses of Stevia to both male and female hamsters to see if their fertility would be affected. Even though 2,500 mg a day was administered ( a human dose is about 2 mg), there was no evidence of decreased fertility.”
Here is a link to the post. http://natural-fertility-info.com/does-stevia-cause-infertility.html