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Aspartame: Insulin & Health Effects ?



I feel concerned about aspartame, as I'm in a fat loss diet, because I've read that aspartame may create an insulin response :

Dr. Jonny Bowden : 12-10-2008

However I found quotes of another study :

Another one : http://www.ncbi.nlm.nih.gov/pubmed/7652029

But there is some articles or site claiming that aspartame induces an insulin response, or may induce it (like Dr. Jonny Bowden himself).

Being in the Anabolic Diet, where insulin should be kept at bay most of the time, I feel concerned by this issue, and would like to know your opinion on the subject, or even better to read other studies I migh have overlooked.



I don't have any expertise, but of all the artificial sweeteners, the one that I seem to doubt the most (as far as long term safety) is aspartame. Just my opinion, and it's based on pretty superficial reading, so if anyone wants to share their expertise, please do.

I was just reading about Acesulfame Potassium (Ace K) which may raise insulin levels.

I'm interested in Stevia, which may increase insulin sensitivity (???) according to at least one website anyway.

It can be tough to form an educated opinion because the various sweetener companies seem to put out information that is critical of their competitors. And information on nutrition is always developing and being updated. And it's hard for a layman to read studies and know if they are worthwhile. So I will be watching this thread.


There have actually been numerous studies done on how artificial sweeteners can give a response to the brain which increases insulin sensitivity. However, I believe that they increase the desire for "bad" foods, but will not actually increase insulin sensitivity...Does this make sense?

Anyways, here is a Q&A from www.elitefts.com

Here's another against themhttp:

Diet drinks have mixed reviews. I don't think they effect insulin sensitivity a ton, but there are other dangers most likely that they may possess.


Most of what I have read on the topic leads to what ebomb stated. It increases the want for bad food, but doesn't necessarily spike insulin. I generally stay away from aspartame and stick to either sucralose or stevia. In today's food industry it is hard to get away from artificial sweeteners as most food companies add it to reduce stated sugar content and appease the ever growing number of low-carbers (not hating on low-carb).


don't mind the ruhtard


Type 1 diabetics are incapable of producing insulin, and type 2 diabetics are resistant to its effects, so diet cokes would not bother them anyways. If diet cokes raised blood sugar it would be a different story but they don't because..well they're diet.


beat me to it!


that's what I'm getting at. Aspartame won't cause insulin problems.


Everything in moderation? Or if you're really paranoid, drink diet soda as part of your para workout supplementation.


Eating protein high in luecine or BCAA's would spike insulin. I'm sure you do that and your fat loss is fine. Insulin or not, it's not something to worry about. Remember, not all people diet down "insulin free". Many diet down using moderate amounts of carbs.

I feel, if these artificial sweetners help you enjoy your meals more and keep you on track they are definitley worth it. Its all about what diet you can sustain for a while without falling off the wagon.


lol I don't want to hijack but what I was saying that your example is faulty - even if aspartame DID cause an increase in insulin, the effects would not be seen in the people you cited because they, diabetics, do not produce it or are resistant to it, so them drinking it would not support the theory that artificial sweeteners or aspartame specifucally does not produce insulin.

I had a long diatribe typed out but I'm too rusty to know if its correct so like elusive and rizza said, this really shouldn't affect your physique goals provided kcal are appropriate - your body has too many regulatory mechanisms to be thwarted by some small insulin increase in the absence of blood sugar increase.


I agree that a protein shake will raise insulin, even more if there is Leucine added, and that insulin is then useful to drive AAs into the muscles. Also, the only food where there is aspartame in my diet is in protein shakes, so based on insulin, nothing dramatic I guess.

However, I know that carbs and AA can raise insulin, but I though that aspartame did not. If it does, that's quit disturbing (any problem with ketogenic diet ?).

Also, there is the point of health. Having read many articles, I either find that aspartame is as safe as one could think, or is as lethal as inducing brain cancer (and a lot more).

Finally, as I noticed that Biotest products I've checked (Metabolic Drive, Grow Whey) do not have aspartame, but instead sucralose (much more 'loved' in articles and studies), that put me in a kind of paranoia about aspartame (enforced by Dr. Jonny Bowden opinion).

Every opinion is welcome.
(I hope my english is readable...).


wow, you're right. I'm retarded, that's what I get for replying to technical shit right out of bed in the morning. I got ya, don't mind the ruhtard


Why are you only concerned with Aspartame? There are plenty of no sugar sweeteners. If aspartame causes an insulin spike then sucralose and stevia should do the same. Personally, I'd be more worried about the neurological effects of aspartame than the insulin effects.


Place this in context. Transient insulin stimulation, absent any CHO, is a good thing (you're on the AD). As you know, protein foods and aminos also stimulate insulin far more than people realize. They alone are sufficient to trigger post-prandial anabolism and anticatabolism (with respect to muscle). Now even IF artificial sweeteners were to stimulate insulin there are a few things to consider:

1) Considering your diet, insulin would actually work to drive aminos into muscle.
2) Absent any substantial CHO, you will not fill glycogen levels and thus will not stunt usage of free fatty acids for energy.
3) Most people don't drink all that much diet pop anyway. Maybe a few per day.

So even IF aspartame spikes insulin, you would derive the postives of insulin with respect to muscle and avoid the negatives with respect to burning/not burning body fat.



You are right, I formulated my question poorly. I was concerned about both insulin effects and health, I'll see if I can edit the title of the topic.

Not all sweeteners are created equal. I've read on one study that acesulfame-k does create an insulin response (http://www.ncbi.nlm.nih.gov/pubmed/2887500), while sucralose seems not (Am J Physiol Gastrointest Liver Physiol. 2009 Apr;296(4):G735-9. Epub 2009 Feb 12. : Effect of the artificial sweetener, sucralose, on gastric emptying and incretin hormone release in healthy subjects.)

Speaking about neurological/health effects, aspartame is not loved by Jonny Bowden, see a detailed argumentation at this link (I just found it) :

After doing a quick search, someone I do not know, Dr. Janet Hull, is in war against aspartame and sucralose too !

Finally, an article in favor of sucralose :

I guess I'm going nowhere lol I hesitate to stick with aspartame protein shakes, or to switch to sucralose (Biotest) ones.


EDIT : just saw your post DH, thanks for reassuring me about insulin and AD, fat burning impairment was one of my unformulated (still answered by you!) concern :slightly_smiling:


Sure G76,

But as far as a general health concern, that is still up in the air it seems. Some consider them excito-toxins/neuor-toxins, and only time will tell.

So, if taken in moderation and made part of a quality dietary structure, I think that aspartame (at least due to it's "age") seems fine. But further research may say otherwise.

But on the insulin issue, at least as far as I understand, we are just fine. Now with certain sugar alcohols, thats another story...



Oh, and just for the record, I bite the bullet on taste and avoid any artificial ingredients in my protein as best I can. I just add some heavy cream and drink it. Its one thing to have a diet cola or two per day, but possibly quite another to consume large dosages in food stuffs. I eat sometimes as much as 200g of protein per day from powder, so I restrict aspartame, etc.. from being added.

Again, I'm trying to be cautiously prudent. I have no hard eveidence to back this up.