What Is Type 3 Diabetes? Insulin Resistance In The Brain That Could Trigger Alzheimer’s
Most people are aware of type 1 and type 2 diabetes, but did you know there is a type 3 diabetes as well! It is a more obscure term. Although it is not an accepted medical diagnosis, type 3 diabetes has been discussed in the literature as a possible relationship between insulin resistance in the brain and Alzheimer's disease. This link has been described to help explain how metabolic disorders impact brain health, causing cognitive decline and dementia.
Type 3 diabetes is more of a misnomer because it should not be confused with type 3c diabetes, which relates to pancreatic dysfunction. The term "type 3 diabetes," on the other hand, has been loosely used by some scientists to analogously propose that Alzheimer's disease is strongly implicated with insulin resistance in the brain.
This concept was conceptualized by Dr. Suzanne de la Monte and Dr. Jack Wands of Brown University in the year 2008. This hypothesis postulated that Alzheimer's disease may be called type 3 diabetes for it bears many similarities with glucose metabolism disorder type 2 diabetes. Their concept arises from the basic principle that insulin is fundamental to blood sugar regulation, but it is also the case with the brain. When brain cells become insulin-resistant, they lose access to glucose, impairing their function.
Research published in the Journal of Diabetes Science and Technology supports this hypothesis by indicating that insulin resistance can be a significant contributor to the occurrence of dementia, also referred to as Alzheimer's. The symptoms of memory loss and diminished reasoning are associated with impaired glucose metabolism in the body, especially in the cerebral tissue.
Although type 3 diabetes is not a "medical term," its symptoms correlate well with Alzheimer's diseases that are known to reduce the ability to think in an efficient manner and bring down brain health. These signs are:
- Loss of memory, especially short-term.
- Poor judgment and judgment ability
- Failure in recognizing people or places familiar once.
- Failure in the process of reading, writing or processing numbers
- Anxiety, agitation, or mood changes.
- Disorganized thoughts or confusion
- Lack of impulse control
As the disease advances, patients may be afflicted with severe complications including an inability to swallow or control their bodily functions. In the final stages, most patients die from fatal complications such as aspiration pneumonia.
This may not be well understood with regards to type 3 diabetes, or the exact link between insulin resistance and Alzheimer's disease. Some identified contributing factors include the following:
Insulin acts as an important regulatory mechanism of brain functions such as memory and cognition. The reduction in insulin signaling may impair metabolism of brain cells, thus bringing about neurodegeneration.
These diseases show a strong relationship and those individuals diagnosed with type 2 diabetes have double chances of getting Alzheimer's. In the two, the main causes can be chronic inflammation, oxidative stress, and a defect in glucose metabolism.
Insulin resistance associated with obesity, stress, and an unhealthy diet is considered a cause that may increase the chances of Alzheimer's disease.
Researches in Frontiers in Neuroscience and The Lancet Neurology have also highlighted that drugs used for antidiabetic medication may be crucial for the prevention or at least slowing down the course of Alzheimer's.
In 2022, in a study in Pharmaceuticals, researchers studied biomarker uptake in brain regions implicated in the faulty uptake and metabolism of blood sugar in Alzheimer’s patients.
Emerging Therapies
Research into such treatments as intranasal insulin has also been promising. Intranasal delivery of insulin directly to the brain has been reported to enhance glucose uptake by brain cells, improve memory, and boost cognitive performance. While such clinical trials have been shown to be successful, additional research is needed for safety and efficacy.
Medications
For patients being aggressive or agitated, antipsychotic drugs may be prescribed; however, therapies such as cognitive rehabilitation as well as cognitive stimulation therapy serve to preserve memory and executive function.
Lifestyle Interventions
Diet, exercise, and stress management are critical in preventing and managing insulin resistance. A review in the Journal of Alzheimer's Disease also highlighted the benefits of Kirtan Kriya meditation, which can regulate genes involved in insulin and glucose metabolism, improve sleep, and reduce inflammation.
Although type 3 diabetes is not officially recognized, its connection to Alzheimer’s disease underscores the importance of proactive measures for brain health. Some prevention strategies include:
1. Healthy Diet
Consuming a balanced diet rich in antioxidants, whole grains, and healthy fats may support brain health.
2. Regular Exercise
Physical activity improves insulin sensitivity, reduces inflammation, and enhances overall metabolic health.
3. Stress Reduction
Mindfulness practices, including meditation, have been shown to lower stress levels, which can reduce the risk of cognitive decline.
The term type 3 diabetes brings out the complex relationship between metabolic disorders and brain health. Even though it is not a recognized medical condition, the concept emphasizes the crucial role of insulin in brain function and its possible contribution to Alzheimer's disease. Continued research will hopefully provide hope for therapies such as intranasal insulin and lifestyle modifications.
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From physical problems like fatigue and vision problems, people who survive the deadly bacterial meningitis are likely to live with long-term fatigue and vision problems, as well as be at high risk of suicide, according to a new study.
The study comes as the UK is experiencing an outbreak of meningitis in Kent, that began among students who visited Club Chemistry in Canterbury between March 5 and 7.
Although bacterial meningitis is treatable, it requires prompt, often immediate treatment for better recovery. Yet patients are likely to face the risk of fatal or long-term complications -- from physical, psychological, and social impacts, said researchers from the University of Otago, The Conversation reported.
The new findings, based on 16 cases from New Zealand, who reportedly suffered the fatal disease, showed that multiple chronic after-effects is permanent in some, while in others, it dragged on for years. The effects include:
"Our findings demonstrate that bacterial meningitis is much more than a life-threatening infection. It is an acute disease with serious, chronic after-effects which are poorly understood and often go unrecognised," the researchers said.
The bug that causes the infection has been identified as the known strain of meningitis B, and MenB vaccines will be offered to 5,000 students living in the University of Kent halls of residence in Canterbury.
Meanwhile, the UKHSA chief executive, Susan Hopkins, said the outbreak "looks like a super-spreader" event with "ongoing spread" through universities' halls of residence.
"There will have been some parties, particularly around this, so there will have been lots of social mixing. I can't yet say where the initial infection came from, how it's got into this cohort, and why it's created such an explosive amount of infections," she added.
As per Trish Mannes, UKHSA Regional Deputy Director for the South East, even after two doses, the MenB vaccine “does not protect against all strains of meningococcal disease, nor against all infections that can cause meningitis. It also does not prevent the bacteria from being carried and spread in the community”.
The UKHSA thus warned people to be aware of the signs and symptoms of invasive meningococcal disease, and to seek immediate medical attention if they or anyone they know develops these signs and symptoms.
Common symptoms include:
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Being tall can have its advantages, but a new genetic study linked height with significant health problems, such as a higher risk of developing heart disease and endometriosis throughout one's lifetime.
While genetics and environmental factors together influence a person’s height, the stature can also prove to be a risk factor for determining the risk of atrial fibrillation, which occurs when the heart quivers rapidly and erratically instead of beating regularly, said the researchers from the China Medical University Hospital in Taiwan.
“By integrating genetic data across multiple East Asian biobanks, we show that the genetics of stature is linked not only to growth-related traits but also to clinically relevant outcomes—most notably atrial fibrillation and endometriosis," said the team in the paper.
"These results suggest that stature-related polygenic scores could help improve early risk stratification in East Asian populations,” they added.
Also read: Woman Left Medically Infertile After Seven Surgeries For Endometriosis That She Did Not Have
The team led by Fuu-Jen Tsai conducted a large-scale genetic analysis on people of East Asian origin. They analyzed 120,000 Han Taiwanese individuals and compared them with 27,966 controls with familial short stature (FSS) -- a harmless condition where people are short due to inherited genetics -- to find genetic factors.
The study also linked a person’s height to overall body size and lung function, as well as cardiovascular traits and reproductive traits, including the age when menstruation starts.
Their findings, published in the journal PLOS Genetics, identified 293 genetic variants linked to height and five linked to familial short stature.
The genetic variants responsible for tall stature increased the risks of both atrial fibrillation and endometriosis. In comparison, the genetic factors for short statures offered a slight protection against endometriosis.
The results proved that taller stature increased the risk of atrial fibrillation independently. But the risk of endometriosis was determined through menarche/weight in taller people.
A 2020 study from Denmark shares a possible explanation for the link between height and increased risk of atrial fibrillation: the rising estrogen levels.
Estrogen is a hormone known to promote the growth of the lining of the womb and is also believed to play a role in growth spurts during puberty.
The study, published in the Annals of Human Biology, showed that taller and slim girls in childhood had a high risk of developing endometriosis. The study also marked a lower body mass index as an increased risk of endometriosis.
However, further research is needed to validate these associations and inform clinical applications.
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Early monitoring among younger populations has been the primary focus of the recently released American Heart Association (AHA) 2026 cholesterol guidelines.
The deliberate shift is reportedly based on new evidence about how heart disease develops over time.
Speaking exclusively to HealthandMe, Dr. Nils P Johnson, Professor of Cardiology, University of Texas, Houston, US, shared that atherosclerosis, or the buildup of plaque in arteries, doesn’t suddenly appear in middle age; it begins silently in youth.
That is why the AHA guidelines highlighted the importance of early screening.
“Cholesterol risk is really about long-term exposure. Just like years of breathing polluted air can damage your lungs, cholesterol builds up in the body over time. It’s not just about how high your levels are at one moment—it’s about how long you’ve lived with them. For example, one person might have very high cholesterol for 30–40 years, while another has moderately elevated levels for 60 years. Over time, their total exposure can be similar—and so can their risk," Dr. Johnson said.
What this means in practice is that treating cholesterol is about reducing total lifetime exposure.
The cardiologist explained that there are two ways to do that: lower cholesterol levels or start treatment earlier.
"Both approaches achieve the same goal—shrinking the overall ‘cholesterol burden’ by reducing how much cholesterol is in the body and how long a person is exposed to it,” the expert said.
As per the Global Burden of Disease Study 2021, the burden of heart failure in adolescents and young adults aged 10–24 years is increasing globally.
The guidelines call for early intervention through early screening and healthy lifestyle changes, starting from childhood.
It recommends:
"They encourage us to think beyond the usual 5- or 10-year risk window and consider the long-term picture—what might happen 20 or 30 years down the road for someone in their 40s or 50s,” Dr. Johnson told HealthandMe.
Also read: ACC/AHA Cholesterol Guidelines 2026 Explained: Start Screening For Cardiovascular Diseases Early
The heart expert also stated that chronic conditions like heart disease require long-term management—sometimes for decades—unlike an infection, where a two-week antibiotic course resolves the problem.
“One of the biggest challenges I see in clinics is that patients often come in after a dramatic event—chest pain, a heart attack, or a procedure. Alongside immediate treatment, I prescribe medications and recommend lifestyle changes. And then patients ask, ‘How long do I have to do this? This reflects a very different mindset”.
Dr. Johnson urged cardiologists and other healthcare workers to help patients understand, accept, and sustain these changes over the long term.
“Adjusting to the reality that life will be different for years or even a lifetime is not easy, but it’s essential,” he said.
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