Age of your type 1 diagnosis

Back when I was diagnosed in 1970 at the age of 8, it was so simple. If you were a child, you had type 1, if you were an older adult, you had type 2. There wasn’t any discussion about right or wrong diagnosis or what treatment you needed.
My question is, what happened? I noticed when I was on MyGlu that the average age for type 1 diagnosis was 19 and 38% of type 1’s are diagnosed as adults. Is it really due to the fact that we are not as physically active as we use to be? Is it because we don’t eat as well as before? Is it because we are just staying older longer and things catch up with us?i read all of our stories and mine feels like it is not the norm. I read these stories and feel.horrible for how many are misdiagnosed and why this is still happening? I read all your stories and think, wow it was pretty darn clear when we got my diagnosis, drinking, peeling, weight loss, sleepiness and of course coma kinda finished it off. But wow, some of you have gone through hell and back trying to get an answer.
So why do you think there has been such an increase in adult’s getting the type 1 diagnosis? This is not my dark thinking here, but could this be that survival of the fittest? Are we going to survive this epidemic? Or will this be ours doing? I know this sounds like gloom but I really don’t understand why and how we have had such a huge shift. And I remember back in 1970, I knew no one in any of my schools with diabetes. There just wasn’t a lot of us around. Now, I’m sorry to say, we are everywhere. Am I crazy? Just wondering?
And finally there is a retreat forums adult type 1’s TCOYD in San Diego in June!


I was diagnosed as Type 2 at age 40, and two months later (at age 41) re-diagnosed as Type 1 based on antibody tests. I didn’t eat or “sit” my way into either diagnosis. I’ve always eaten well, and I’ve always been active, fit, and healthy as both a child and an adult.

I think the whole child vs. adult split up until the 1980s was simply enough a misunderstanding based on lack of knowledge. We understand the genetics of Type 1, Type 2, MODY, MIDD, and other forms of diabetes mellitus now in a way that we didn’t (and couldn’t) know before that period. We now know that Type 1 isn’t as simple as an autoimmune attack on beta cells during childhood. Type 2 isn’t as simple as the “natural” result of obesity and overeating in adults. It’s all far, far more complicated than that oversimplification.

I think the increase in adults is a change in terminology and diagnostic criteria. In the good old days, you were either “insulin-dependent” or “non-insulin-dependent.” There was also “insulin sensitive” and “insulin resistant.” There have been “fat” and “skinny” diabetics. I think what has changed in the last thirty years is pretty simple: better genetic testing and understanding of genomic science (see Trialnet); more and better antibody-tests that can be used to diagnose “Type 1” DM; a greater focus on metabolic disorders in general as the population ages and struggles with obesity-related disorders.

The last one is somewhat controversial, since obesity and Type 2 are correlated, but not necessarily in a causal relationship with each other (or at least not one we understand). The side-effect of a greater focus on Type 2 and obesity is that more Type 2s are being diagnosed than ever before. Like me, if someone comes into a doctor’s office and is over age 40 and/or obese, they automatically get diagnosed as Type 2 regardless of presentation. “It’s statistically most likely.” Well, I wasn’t obese, I was over 40, but it turns out I don’t have Type 2. I’ve heard as many as 20% of Type 2 diagnoses later turn out to be Type 1, MODY, or MIDD. But if an adult walks into a GP’s office and has symptoms of diabetes, and their glucose metabolism is compromised, it’s almost certain they’ll be diagnosed as Type 2.

My old doctor (I found a new one) was young, intelligent, and didn’t believe that adults could really be Type 1. He believed, and told me, that my “Type 2” was probably because I’d put on 5 lbs since I started graduate school in my mid 30s. I believed him, and felt full of self-loathing for having “done this to myself.” I now know that even if I was Type 2, it wouldn’t have been “my fault.” But I thought I knew enough to know that people “at their way into Type 2” in adulthood. Or they were lazy… it is, after all, the “fat and lazy” disease.

Type 1, as far as I know, doesn’t have anything at all to do with diet or exercise (or lack thereof), although both are important considerations when treating Type 1. Simply, genetic susceptibility, infection by various viral diseases, and then a follow-on autoimmune attack on beta (and more) cells in the pancreas are the “cause” of Type 1. Doesn’t matter if the country is becoming more obese, sitting around more, or anything else. As a scientist, the only thing I can think of that would lead to a higher percentage of the population being diagnosed as Type 1 than in a previous generation are the following:

  • New diagnostic criteria (see above);

  • A higher incidence of the Type 1 genotype in the population (which may be happening as Type 1 is now treatable effectively in a way it wasn’t 100 years ago–there is a likelihood that many Type 1s are passing their genes on now, when that is far less likely in the pre-exogenous-insulin past);

  • And a greater incidence of the types of viral infections that can precipitate an autoimmune storm leading to development of antibodies attacking beta cells (could happen as population density increases, but that’s really outside of my level of understanding).


Hm. I’m kind of at odds with a lot of what you’re saying, so please take this in the spirit of comparing impressions not a criticism. :slight_smile:

From reading around here it seems there are actually two patterns for non-childhood onset of auto-immune diabetes: one is pretty much the same as childhood onset, which is what I and a number of other TUDers experienced. I was dx’d in 1983, just after my 28th b’day. No question about the diagnosis: symptoms came on and became acute over just a few weeks, probably precipitated by a nasty cold I’d had just before it all started. Others experienced a pattern that develops much more gradually, such that it is frequently misdiagnosed as T2. I believe that’s what they mean by the “Latent” in LADA.

Do you mean more adults getting T1? I’m not sure that’s true without seeing some statistics. Certainly “the diabetes epidemic” refers to T2; T1 is still a small minority.

Or rather, if a child, “juvenile” and if an adult “mature onset” (i.e., not auto-immune but insulin-resistant), right? Even back when I was dx’d my diagnosing dr told me it was far less unusual than most people assumed to get it at my age, and that was why there was a move on to use a different nomenclature, “Type 1” and “Type 2,” though in 1983 it hadn’t come into broad usage yet. My dx was “Diabetes Melitus (Juvenile type)” and still reads that way on my medical records.

In 33 years with T1 I can count on one hand the number of other T1s I’ve actually met in person. I spent a long long time feeling very much alone with it. Over the last 5-6 years that has changed enormously, but only thanks to the DOC (and this site in particular). In the offline world I still only know two people with whom I have any kind of regular contact who have it. Both of them got it as adults–one was the same age I was, 28, and the other was older, in her 40s I believe.


The irony, of course, being that the terms “Type 2” and “Type 1” were specifically introduced because “juvenile onset” and “mature onset” didn’t accurately map to the underlying condition, or so I was told back in '83 when I was dx’d and they weren’t yet in common use (see my comment below). And yet nine times out of ten “Type 2” seems to be used synonymously with “you’re an adult so it can’t be Type 1 (which means 'juvenile,'don’t you know that???).” If my dr who told me “we still call it ‘juvenile’ even though you’re 28, but that’s changing” could have foreseen… Just shows how impotent semantics can be in the face of stubborn, uninformed assumptions. FAIL!

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I’ve only been diagnosed for 3/4 of a year, but I’ve met exactly one Type 1 in person, and two Type 2s who would acknowledge that they were Type 2. I’m sure I’ve actually interacted with more (I think just under 9% of the entire US and Canadian population has DM of some variety), but it’s rare to identify another diabetic in the wild.

I do agree that as someone with Type 1 who had a juvenile onset, I do feel in the minority in the diabetes online community. It’s somewhat rare to come across people who were diagnosed before adolescence. But I don’t think the DOC is reflective of the diabetes population overall. And I agree with @David49 that I don’t think the demographics have changed (at least not without seeing some data) but rather diagnostic tests have gotten better so that adults who may have just been considered to have Type 2 (and just happen to need insulin and be insulin sensitive for some reason) are not properly diagnosed as having Type 1.

Autoimmune conditions and allergic conditions (which are also caused by the immune system going rogue and attacking things it shouldn’t) have all been on a sharp rise for the past decade or two. Some of it might be more genetic predisposition, since people with these conditions are surviving when they wouldn’t have a hundred years ago. But I think there must be some environmental factor(s) outside of our individual control driving the increase. I’ve done quite a bit of reading, and have heard everything from an altered intestinal microbiome to chemicals and toxins in the environment to factors such as chronic stress suggested as “new factors” that weren’t around fifty or a hundred years ago, in addition to the viruses and other factors that have always existed.

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I think a lot has to do with what sites you frequent as well. I recently joined “Beyond Type 1” which seems to skew more toward juvenile onset. The “online forum” model which has been around since the pre-WWW Internet (I know, I was there) tends to select toward older people, which of course includes people dx’d as kids who are now adults, but mitigates against younger people to some extent.

Separate conversation, but I find “Beyond Type 1” quite inferior to TUD as far as encouraging actual interaction between participants goes. The comment threads are 99% discrete posts that only rarely if at all become conversations in which participants respond to each other’s views, and very little sense of “community” in the sense that you’re seeing familiar faces who return frequently and become recognizable personalities the way you do here.

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I was diagnosed with T1D at the age of 30 but I know I had symptoms during the year leading up to my diagnosis. I knew precious little about diabetes then. I remember hearing the descriptors, insulin-dependent diabetes and non-insulin dependent diabetes as an attempt to communicate the distinction between T1 and T2, even though that was wrong! I was lucky to get the correct diagnosis from a young general practitioner doctor.

I’d have to agree largely with most posters here. I suspect that the increase in adults being diagnosed as Type 1 diabetics is simply due to a more nuanced understanding of the condition.

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I don’t know what to think. I come from a family where my oldest brother was diagnosed at 13 in 1971 (I was 5 at the time). Then I developed it too—38 years later. So why did my brother and I develop T1 30 years apart (he was 13, I was 43)? Good question. I have no idea.

My “latency” was both in age diagnosed AND in time until I needed mealtime insulin (18 months). But the initial presentation was just the same as my brother: Excessive thirst, excessive urination and rapid weight loss. I dropped 20 pounds in about 4 1/2 weeks–and I did not have the weight to lose!

Everyone’s experience of diabetes is different, but I think T1s who developed it as adults usually have a more herky-jerky journey. (Try to say THAT fast five times in a row!)

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As a type 2 I would answer that I was 53 when I was first diagnosed as type 1. Now you may ask how does that make sense? Well that was the first time that my endo “coded” me as 250.01 under ICD-9. This coding is “Diabetes mellitus without mention of complication, type I [juvenile type], not stated as uncontrolled” and corresponds to the new code E10.9 “Type 1 diabetes mellitus without complications” under ICD-10. This diagnostic coding decision has been used pretty consistently by my endo in all my insurance filings since then. I am sure it is the reason that I had my CGM immediately approved.

She made this change even though I came up all negative for antibodies and even was negative for MODY. I do have a low c-peptide (0.7 ng/dl last time it was checked) and I appear to be fully insulin dependent (and basically non-responsive to type 2 medications). My endo calls me “ideopathic type 1.” I still consider myself type 2 and consider the label type 2 to just mean “diabetes of unknown cause.” That certainly fits me.


It’s interesting to see the change in the ways doctors approach the T1/T2 diagnosis. I have 3 relatives diagnosed with T1 diabetes as adults (including my grandfather who was diagnosed as an insulin-dependant diabetic in 1959 at age 30.) When my dad was diagnosed in 1991 his doctor automatically assumed he had to be T2 because of his age and he’s had other doctors tell him the same thing even after he was correctly diagnosed. I’ve always gotten comments from doctors that my family history is very unusual since they were not used to seeing adult-onset T1.

On the other hand, my doctors assumed LADA until I tested negative for autoantibodies and still are hesitant to say T2 for me. Although I still run into some doctors who don’t get adult-onset T1 like my daughter’s pediatrician.

Mary Tyler Moore was diagnosed with Type 1 diabetes ~1969, at the age of 33. She was not misdiagnosed. So back when the OP was diagnosed with Type 1 as a child, adults were being diagnosed with Type 1. I have a 1958 book on diabetes by Dr. Henry Dolger, a well-known diabetologist of his time, in which he describes adult-onset Type 1 and says it is more common than childhood-onset Type 1. Back then, doctors had to look at the phenotype and disease process, to really look at the patient and be a true medical detective (I know, shocking, typically now if you are an adult and have a FBG >125 mg/dl, you are labelled Type 2, given metformin, and sent on your way, without a true assessment made). I actually think that JDRF, which started in the 1970s, was the originator of the myth that Type 1 diabetes is a childhood disease. The parents of kids with Type 1, while well-meaning, wanted to light a fire and also distinguish Type 1 from Type 2 diabetes (and back then, most Type 2s were diagnosed >40 years of age). Just my two cents!


I was diagnosed last year as Type 1 at age 45. The change happened very quickly over a period of about two months and followed a tough episode of the Norwalk virus. There are many in my family with various autoimmune issues however I am the only Type 1 so I assume predisposition triggered by the virus but who knows for sure.

This makes sense. Although I don’t know how old she was at diagnosis, my great-grandmother was diagnosed as Type 1 in adulthood, likely in the 1950s (my mother always knew her as a Type 1). I’m not sure they would have used the “term” Type 1, but she was considered to be insulin-dependent, insulin-sensitive before 1950 (my mom’s earliest memories). And my grandmother was also diagnosed as Type 1 in her 50s, although that wouldn’t have been until the 1980s.

Meanwhile, my youngest brother and I were both diagnosed as Type 2 (he at 22, me at 40) and then re-diagnosed as Type 1 after weirdness and antibody tests. I suspect that many GPs have either gotten “lazier” in their approach to diagnosing diabetics, or there simply aren’t as many GPs to go around as their used to be. Or they don’t have enough time. So instead of digging in and making a truly educated best-diagnosis, many doctors just go with the percentages. I just met with my new GP for the first time this morning. She said that diagnosing a male at 40 as Type 2 was exactly what she was taught in med school, and was glad that I dug in a little deeper.

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I was told that was the likeliest path to Type 1: a heritable genetic sequence associated with susceptibility to autoimmune disorders; and an environmental trigger in a viral attack of various types. We have rampant autoimmune disorders in my family ranging from lupus to Type 1, and I myself got sick with coxsackievirus B a couple of years ago. If the “genetic susceptibility and subsequent infection” model of Type 1 is right, that is likely the route by which I developed T1 at 40.

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I think right on two counts, David, lazy and no time. When I was writing a blog on the psychology of misdiagnosis, as in why do doctors misdiagnose people as Type 2 when they actually have Type 1, I “interviewed” two doctors (my friends and family are subject to my investigations!!!), a close friend and my cousin, and my close friend (a pediatrician) said, “Doctors are lazy!” and my cousin (family practice doc) said, “No time!”


Bull’s eye. Even today, diabetes gets fairly short shrift in medical school. There’s just too much material to learn and not enough hours in the day, so real in-depth education in specific topics is often reserved for specialists and simple rules of thumb are presented in the general curriculum. “If the patient is a mature adult, it’s sure to be Type 2” is only one of them. (Now there’s a disquieting thought for you.)

No misdiagnosis for me. Was the classic case, 5 years old, losing weight, tired and peeing all the time. Mom brought me to the doctor’s office, and was sent straight to hospital after merely noting my breath. There may have also been an urine or blood test, but don’t remember those details. That was 51 years ago.

I didn’t meet another type 1 in person until my late teens. I did find out years after high school, that there were several other T1Ds in my class (out of 600+). But back then, I was taking one injection before breakfast, and occasional urine checks at home. So no trips to the nurse, meters, pumps, cgms, etc to have visible signs.

In my first year of college (still doing 1 injection/day), another student in my dorm was diagnosed T1D, probably 19 or 20 years old. I thought it was weird to get it that late, and think it was still referred to as ‘juvenille’ diabetes.

Before going to the Diabetes UnConference the last 2 years, I would estimate only 25-30 other T1Ds that I met in person in my lifetime, in various support groups.
The first UnConference had about 100 people, and they added up the years of diabetes. It was almost 2000 ! It was quite an experience.

Unconference 2015

I was diagnosed as T2 at the age of 35 in 2000. ~14 years later after “controlling” my BGs with diet and exercise for 10 years and trying various meds (none of which worked for very long, if at all) for the next ~4 years I was rediagnosed as T1 when an insulin antibodies test came back positive.

On a personal note I have the following family members all diagnosed as T2: 2 sisters, my mom an uncle and a grandmother, all from my mom’s side of the family. I work with a T2 and have met 3 young people who were diagnosed T1 as children, one of which just married one of my nieces.
Diabetes has been a part of my life for a long time.


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