Least Toxic Insulin

I’m going to my endo in a couple days, and I’m really concerned about the levels of toxins in my insulin. I’m on Apidra and Lantus, which have two of the highest quantities of m-cresol. For a while I had my heart set on going porcine, ordering hypulin through Canada, but now I’m not sure because that stuff also contains m-cresol. It doesn’t seem to be worth the extra money and effort. M-Cresol, in studies done by the US National Toxicology Program and US EPA, was found to be “slightly to moderately toxic” and a “possible carcinogen.” On the other hand, Apidra and Lantus have shorter ingredients lists – they don’t have phenol, zinc, mannitol, disodium phosophate dehydrate, etc. Phenol is highly toxic.

Everything seems toxic. No good options here. Anyone see something I haven’t?

APIDRA is a sterile, aqueous, clear, and colorless solution. Each milliliter of APIDRA contains 100 units (3.49 mg) insulin glulisine, 3.15 mg metacresol, 6 mg tromethamine, 5 mg sodium chloride, 0.01 mg polysorbate 20, and water for injection. APIDRA has a pH of approximately 7.3. The pH is adjusted by addition of aqueous solutions of hydrochloric acid and/or sodium hydroxide.

LANTUS consists of insulin glargine dissolved in a clear aqueous fluid. Each milliliter of LANTUS (insulin glargine injection) contains 100 IU (3.6378 mg) insulin glargine. Inactive ingredients for the 10 mL vial are 30 mcg zinc, 2.7 mg m-cresol, 20 mg glycerol 85%, 20 mcg polysorbate 20, and water for injection.

Each milliliter of LEVEMIR 10 mL Vial contains the inactive ingredients 65.4 mcg zinc, 2.06 mg m-cresol, 30.0 mg mannitol, 1.80 mg phenol, 0.89 mg disodium phosphate dihydrate, 1.17 mg sodium chloride, and water for injection

NovoLog Mix 70/30 is a uniform, white, sterile suspension that contains insulin aspart (B28 asp regular human insulin analog) 100 Units/mL. Inactive ingredients for the 10 mL vial are mannitol 36.4 mg/mL, phenol 1.50 mg/mL, metacresol 1.72 mg/mL, zinc 19.6 µg/mL, disodium hydrogen phosphate dihydrate 1.25 mg/mL, sodium chloride 0.58 mg/mL, and protamine sulfate 0.32 mg/mL.

Each milliliter of Humalog injection contains insulin lispro 100 Units, 16 mg glycerin, 1.88 mg dibasic sodium phosphate, 3.15 mg Metacresol, zinc oxide content adjusted to provide 0.0197 mg zinc ion, trace amounts of phenol, and water for injection.

Humulin-N: Each mL contains 100 units of NPH insulin. Nonmedicinal ingredients: dibasic sodium phosphate, glycerol, m-cresol, phenol, protamine sulfate and zinc. May contain: dimethicone, hydrochloric acid and sodium hydroxide. Cartridges of 1.5 and 3 mL, boxes of 5. Vials of 10 mL.

Humulin-R: Each mL contains 100 units of Regular insulin. Nonmedicinal ingredients: glycerol and m-cresol. May contain: dimethicone, hydrochloric acid and sodium hydroxide. Cartridges of 1.5 and 3 mL, boxes of 5. Vials of 10 mL.

Hypurin porcine isophane (fast acting) contains Protamine sulphate Zinc chloride m-Cresol Phenol Sodium phosphate Glycerol Water for injections

hypourin porcine neutral (longer action) contains m-Cresol Phenol Sodium phosphate Glycerol Water for injections

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If you ever break a vial, you know you’re dealing with serious chemicals that you hope are in a small enough amount that your body will be able to deal with them. Ever smell nail polish? paint? weed killer? I have a landscaper who uses natural products, so you know where I stand.
The idea is to work with your diet carbs and protein carefully and to exercise to the point that finally you use the least of these products that your body requires to keep you at about 100 + or - 5. I won’t say lower than that because I’m aware of how easy it is to slip into hypoglycemia unawareness.
I am aware of the phenol and cresol every time I take a shot. But the alternative, not using them, is far worse!!! Smile!

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Wow. I’m always shocked what is in our insulin. Does anyone know if these toxins have some function in the insulin? Is there a reason that they have to be there?

If you take it in large quantities, everything is a toxin. That includes water.

Those chemicals that are present in insulins serve very specific purposes to keep the insulin stable and to buffer their pH. No chemical is present unnecessarily. The concentrations at which these chemicals are present are minute and do not pose any risk to our health.


John Smith, do you have research showing that these chemicals do not posy any risk or is that your assumption? M cresol, for example, is toxic as defined by two different US government agencies.

In light of the three recent European studies showing that Lantus is strongly correlated with cancer, I think there is cause for concern.

Let me throw some food for thought: all insulin analogues are entirely man-made creations which exist nowhere in nature, which is something worth considering. The FDA doesn’t even call them insulin, they are referred to as “insulin receptor ligands” and no, there aren’t any long-term studies on these, those who began using them shortly after approval ARE the long-term studies. You might therefore consider at least using an actual “insulin” molecule, which eliminates Apidra, Novolog/Novorapid, Humalog, Lantus and Levemir from the list of possibilities. In terms of preservatives, you are right about all of these, which are designed to enable manufacturers to make insulin a year (or more) before they are actually used by patients. This is something you already noted, but note that all insulins, including insulin receptor ligands, also contain these preservatives in varying quantities.


Thanks for the reply Scott. If we’re talking about using actual “insulin,” do I have any choices other than hypurin?

As more and more genetically modified foods are shown to have strange effects–weird second generation offspring plants, deaths in rats and various ruminants, behavior abnormalities in humans, etc–I feel like getting off rDNA would more in line with my beliefs.

Thanks for your help.

I haven’t researched it, but was told that the older Regular insulin is less “risky” than the newer analogues. No doubt it contains the same/similar preservatives. Regular works slower, sticks around longer. For me, it’s more effective. I only use rapid acting for corrections.

The potentially dangerous chemicals in insulin is something that has deeply troubled me. Ironic that I’m filtering water, eating organic, avoiding toxins as much as possible & shooting heavens knows what into my body in order to live.

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I manage risk for a living and am also a Lantus user so when this came out I looked through the results to see if this was a risk I needed to avoid. Lets just say I wouldn’t be stopping Lantus any time soon. Of the four studies (the fourth, a UK study, that found no correlation) the German study, which showed the largest correlation had a flawed sample set, and the other three studies were statistically unsound. You definitely cannot say that Lantus is strongly correlated with cancer based on these test.

The German study which is the only one with a reasonable sized sample set was skewed by having the Lantus cohort made up of older patients who are naturally more prone to cancer due to age (look at how the incidence graph for cancer takes off after 45) and obesity (another cancer risk) while the other insulin users were younger and thus less likely to get cancer anyway. In other words this was predictable.

The other three studies all had small numbers of cancers so you cannot draw any conclusions. For example if you get a single cancer in one group and two in the other that is a 100% increase. Once the set size drops below a certain threshold you are in the margin of error and all three studies fell into that case.

There are things worth worrying about but based on those studies Lantus is not one of them. I would like to see proper trials of insulin but for obvious reasons that is very unlikely to happen so studies are the best we will get.


Speaking as someone who has been using porcine insulin since I was diagnosed (30 years ago), I’d say go for whatever suits you best (based on your diabetes specialist’s advice of course).

I was on Pork Insulatard and Actrapid until 2 years ago when I had to switch to Hypurin Isophane and Neutral (as Novo Nordisk stopped making porcine insulins). I don’t have any problems with using them but you have to remember that Neutral (which is the short acting one by the way, NOT the isophane!) takes about half an hour to begin working and lasts over 4 hours. This means that you have to inject about half an hour before you’re due to eat. These insulins don’t really work with the basal-bolus regime for that reason.

For me, because I’ve been used to the routine of injecting half an hour before a meal, I’m not bothered about changing. If you’ve been used to eating whatever and whenever you want, giving yourself a bolus of quick acting insulin before or shortly after the food, you won’t really be able to do this if you switch to the Hypurin insulins. You need to be aware of that if you’re thinking of changing.

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If my late night math is not mistaken, I will be injecting 45.36 g of metacresol per year on Apidrabin my pump… Aye…

Like insulin pump hacking, this just isn't something that I'm worried about. My understanding is that there haven't been any conclusive studies that show an increased risk among diabetics using insulin and cancers. The data just aren't there. I do believe that because I use a pump I have a little less to worry about (because I am only using 1 type of insulin and taking fewer units via the pump than I would on MDI). But is this something I'm losing sleep over? No. Chances are, I'll be dealing with complications from living with T1D for decades long before I'll develop any side effects from the additives in the insulin.

In addition, we're probably exposed to far more chemicals and toxins in an average day. There's so much out there that I'm sometimes amazed we aren't all walking around with cancer!

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This is a interesting discussion. I struggle with the same idea. I stay away from toxins in my food, eat local, farm food, all organic. Clean my house with organic stuff. And then I am injecting toxins into my body 5 times a day? I do think that eating very low carb, 20 grams a day to keep the amounts of insulin injected low is a good thing. I also take only NPH and Regular, mostly because they seem safer because they have been around the longest and the fact that I can get them without a prescription. Then I can say I am on no prescription medications. Its silly really, but psychologically it makes a difference. The more we can do to make us feel happy and well the better.
I still believe with the right therapies, detox etc. A type 1 diabetic can heal. I plan to. Thanks for opening up this discussion.
If something is a known carcinogen, it's not only causing cancer, but creating a toxic environment for all of us.
If the medical matrix is trying to cure cancer by injecting toxic chemicals (chemo-therapy), and putting toxic chemicals in insulin they want us to all stay sick, so they, the medical matrix, can all keep making money!
I believe we can all get well.

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I think your math is wrong, off by a factor of about 100, unless you are taking HUGE amounts of insulin. I compute that 60 units of insulin per day would be 0.69 g of metacresol per year.

Obviously everyone can decide for themselves what their threshold is for taking on additional anxieties, but I have to say, I have more than enough as it is (you know, between trying to live a normal life and keep all my limbs). I tend to doubt that the levels of toxins in insulin analogs are significant, but I wonder how I would react if I did believe it was slowly poisoning me. Would I order animal insulin? Well, I think there are likely problems with animal insulin, too, and the constant nail-biting waiting for my insulin to arrive would wear me down. Would I go back to non-analogues? I used them for most of my diabetic life, and for me, things are so much easier with them that it's almost inconceivable to think I'd have to go back. Ultimately, if I spend significant time worrying about problems which I can't realistically avoid, it'll suck all the joy out of life.
Plus, I drink so much diet coke I'm screwed anyway. Ha!


All of the insulins have toxins in them, pretty much the same ones, even the animal ones. I guess they put them in there so that they don't get contaminated during the long time we use the vial. I've been shooting them up for 42 years and hope to last many more years. I do seem to be pretty healthy and as long as we keep our organs of elimination working we should be ok. I still don't like the idea of directly injecting toxins into my body, but you are right it remains important to keep positive and loving.

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ditto on the diet coke!

funny! love that this showed up again.

i happen to do in office & mail order biofeedback testing for a living, and work with toxins extensively now. ive found that half of people or so will have some degree of allergenicity to some part of their insulin--whether it's the insulin itself, the biproducts, the chemicals in the syringe, who knows. can't comment for sure. the problems will generally respond well to homeopathic antidoting (applying hand succussed dilution of the insulin itself orally or with laser technology) or 250mg or so of dimethylglycine, a supplement that boosts methylation activity.

i personally always responded negatively to R, with notable symptomology (irritability, flushed cheeks, etc). this responded phenomenally to homeopathic antidoting. no longer causes a negative response (other than those youd expect from using R! hah!.

thank you

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I know this is an old post, but I would like to add one thing.

It might seem counterproductive to add known toxins in medications, as they are supposed to heal/help us, but it actually makes sense (to me at least). They are preservatives, and the main function of preservatives in fluid medications is to kill different lifeforms. Think about it - you stick your (possibly) contaminated needles in the bottle, and to stop any bacterial growth in your insulin you have to create a toxic environment for the bacteria (and most like yourself).

Unless you are allergic to phenol and its derivatives, I wouldn't worry too much. Having bacteria growing in your insulin is more likely to be worse than the phenol.

I'll be ending with a personal anecdote. :P
I've just finished a drug trial at my hospital, that was intended to test some preventive medication for diabetic retinopathy, and I went through extensive eye tests. My doctor said if she didn't know from my chart that I was diabetic, she would have thought I was completely healthy (from what my eyes could tell her), and my vision was over 100% (could see all the lines except the last one). This is after almost 10 years of diabetes and me having used no other insulin other than NovoRapid.

So, yeah, I wouldn't worry too much - even though my personal experience is a small sample size, and doesn't constitute a valid scientific analysis. :) My point is that there are so many more pressing and relevant things we can do to improve our health, which have larger effects on our health than the insulin perservatives.


The rDNA insulins are insulin analogues because they have a single amino acid difference between themselves and human insulin. This change is to help with absorption (and I think with onset of action, as well).