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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Amid India's growing burden of high blood pressure among the youth, Prataprao Jadhav, Union Minister of State (I/C), Ministry of Ayush and Minister of State for Health and Family Welfare, said hypertension is emerging as a major public health concern due to worsening lifestyle habits.
High blood pressure is a “silent killer” that is rapidly increasing among India’s youth because of unhealthy lifestyle changes, the minister said.
Ahead of World Hypertension Day 2026, Jadhav noted that the condition often progresses without visible symptoms and can eventually lead to severe complications such as heart attacks and strokes.
“In today’s time, it is essential that we make our communities more sensitive and aware and strengthen awareness about hypertension. Due to changing lifestyles and reduced attention to physical and mental health, hypertension is rapidly increasing even among the youth,” Jadhav said in a video message during the ‘Illness to Wellness Conference on Transforming Hypertension Care: Prevention to Wellness’ organized in the national capital.
He highlighted that the Government of India, under the National Program for Prevention and Control of Non-Communicable Diseases (NPCDCS), is actively promoting population-based screening, early detection, and management through Health and Wellness Centers across the country.
Prof. Rakesh Yadav, Cardiologist and head of the Department of Emergency Medicine at AIIMS, New Delhi, stated that once known to be the disease of the elderly, hypertension is now more common among the youth. The reason — lifestyle changes, the experts said.
“The biggest problem is that despite increasing awareness, people still do not monitor their blood pressure regularly or continue treatment consistently. Hypertension is no longer limited to the affluent or elderly; it is now affecting all sections of society, including children and young adults,” said Prof. Rakesh Yadav, Cardiologist and head of the Department of Emergency Medicine, AIIMS, New Delhi.
“Obesity remains one of the major underlying causes, and regular monitoring of blood pressure and sugar levels, affordable lifelong medication, healthy dietary practices, and weight management are essential to reducing mortality associated with hypertension and related diseases,” he added.
In India, more than 1 in 4 people have hypertension, and cumulatively, more than 90% of adults with hypertension are either undiagnosed, untreated, or treated but live with uncontrolled hypertension.
Experts at the conference also pointed out that modern lifestyles marked by long working hours, constant connectivity, poor sleep, sedentary habits, and rising stress levels are significantly contributing to the growing burden of hypertension and other lifestyle disorders.
Another major concern, they said, is that many people tend to ignore early symptoms until complications arise, negatively affecting treatment outcomes.
“Hypertension is one of the biggest public health challenges today because most people do not take it seriously until complications arise. Nearly one in four adults is affected by hypertension, yet awareness and blood pressure control remain very low,” said Dr. Ripen Gupta, Vice Chairman & Unit Head - Cardiology, Max Smart Super Speciality Hospital, Saket.
Rajesh Bhushan, Former Secretary, Ministry of Health & Family Welfare, said high blood pressure is not limited to urban populations and is increasingly affecting youth in rural India as well.
“The problem of hypertension is as prevalent in rural India as it is in urban India, but because we live in metro cities, we often believe it is only an urban problem. Early detection is extremely important because without early detection, early treatment becomes difficult,” Bhushan said.
Bushan stated that non-communicable diseases impact GDP significantly across countries, and therefore, prevention and timely intervention are critical.
Hypertension should never be taken lightly, said Dr. Sanjeev Singh, Chairperson, FICCI Medical Education Task Force and Medical Director, Amrita Institute of Medical Sciences & Research Centre. He urged people to follow medical advice seriously to avoid long-term complications.
The doctors called for critical lifestyle interventions for prevention and management. This included:
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High blood pressure, or hypertension, is often called a “silent killer” because it may cause no symptoms, but serious damage to multiple organs can occur. Most people associate hypertension only with heart attacks, but its ill effects extend far beyond the heart. Persistent high blood pressure can gradually damage the brain, kidneys, eyes, and blood vessels, reducing both quality and length of life.
The heart pumps blood through blood vessels, which carry blood to every organ. When hypertension is not properly treated, blood pressure remains high for years, and these blood vessels become stiff, narrow, and damaged. This affects blood flow to vital organs that these blood vessels supply and triggers multiple health problems.
One of the most serious consequences is damage to the brain. Hypertension is the leading cause of stroke. A blood vessel in the brain may either get blocked or burst due to excessive pressure, resulting in paralysis, speech difficulty, or even death.
Repeated uncontrolled hypertension can also impair memory and thinking ability over time, increasing the risk of vascular dementia in older age. Many patients are surprised to learn that controlling blood pressure today may help preserve brain function years later.
Hypertension: The Silent Effect On Kidneys
The kidneys are another major target. High blood pressure damages the delicate blood vessels inside the kidneys, gradually reducing their ability to function.
In fact, hypertension is one of the important causes of renal failure leading to dialysis. Unfortunately, kidney damage develops silently and may remain unnoticed until advanced stages. Regular monitoring of blood pressure and kidney function is therefore essential.
The eyes, too, can suffer from uncontrolled hypertension. The tiny blood vessels of the retina may narrow, leak, or bleed, leading to blurred vision or even permanent visual loss.
Eye specialists can often detect signs of long-standing hypertension during routine retinal examination. Sometimes, the eyes provide the first warning that blood pressure has been poorly controlled for years.
High blood pressure also weakens arteries throughout the body. It accelerates hardening of blood vessels, increases the risk of peripheral artery disease, and can contribute to aneurysms — dangerous ballooning of arteries that may rupture unexpectedly. In some patients, hypertension is linked to sexual dysfunction, sleep disturbances, and reduced exercise capacity.
The good news is that hypertension is both detectable and treatable. Lifestyle measures remain the foundation of prevention and control.
Maintaining a healthy body weight, exercising regularly, avoiding tobacco, limiting alcohol, and managing stress can significantly lower blood pressure.
Adequate sleep is equally important. However, many patients also require medicines, and these should be taken regularly even when one feels perfectly well.
Adults should check their blood pressure periodically, especially after the age of 30 or earlier if there is obesity, diabetes, or a family history of hypertension. Early diagnosis and proper treatment can prevent devastating complications later.
Hypertension is not merely a “heart problem.” It is a whole-body disease that silently injures multiple organs. Recognizing this reality is the first step toward prevention, timely treatment, and healthier living.
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The risk of hantavirus spreading is generally considered low, as repeatedly stated by the World Health Organization (WHO) and other global health agencies, after the recent outbreak on the MV Hondius cruise ship. However, a shocking peer-reviewed study has found that the Andes strain of the rat-borne virus can persist in human semen for up to six years.
More concerning is the possibility that the virus could potentially be transmitted sexually even after a person has recovered, according to the 2023 study published in the journal Viruses.
The research, conducted by Swiss scientists at Spiez Laboratory, suggests that hantavirus may survive in the male reproductive tract like viruses such as Ebola.
The research team, which included scientists from the University of Bern and the University of Lausanne, investigated a 55-year-old man who had contracted the Andes strain of hantavirus in South America six years earlier.
The researchers discovered that although the virus was no longer detectable in the man’s blood, urine, or respiratory tract, it was still present in his semen 71 months later.
"Viral RNA remained primarily detectable intracellularly in semen samples throughout the complete study period of almost six years," the 2023 study stated,
“Taken together, our results show that the Andes virus has the potential for sexual transmission,” it added. However, so far no confirmed case of such transmission has yet been documented.
Also read: Hantavirus Outbreak: Critically Ill French Patient On Artificial Lung Support
Hantavirus is not the first virus found to persist in the male reproductive system. According to the study, viruses such as Ebola and Zika are also known to evade the immune system by remaining hidden in the testes for extended periods.
A 2021 Ebola outbreak in Guinea, which resulted in 23 cases and 12 deaths, was later linked to a survivor of the 2014–2016 West Africa epidemic who reportedly transmitted the virus sexually years after recovery.
The testes are considered a biological “safe harbour” for at least 27 infectious diseases, enabling certain pathogens to remain hidden in the body and potentially spread years after a patient has recovered.
Because sperm cells are essential for reproduction, they are shielded from the body’s immune response. However, this immune protection can also create an environment where viruses are able to survive and persist for long periods.
Analysts at Airfinity, a company that tracks global health risks, recommend that male patients should receive “extensive safe-sex guidance beyond the [42-day] quarantine”, the Telegraph reported
The guidance should be “analogous to the World Health Organization’s (WHO) Ebola survivor semen-monitoring protocols,” it added.
The WHO protocols recommend that the semen of male Ebola survivors should be tested every three months and should not be considered virus-free until two consecutive negative test results are obtained.
Until cleared, they should “abstain from all types of sex” or “use condoms consistently and correctly.”
They should also wash themselves “thoroughly” with soap and water after any contact with semen – including after masturbation, according to the guidance.
According to the World Health Organization (WHO), 11 people have been affected by the rat-borne virus so far, of whom three have died.
A Dutch couple is believed to have been first exposed to the virus while visiting a birdwatching site in Argentina.
The WHO has confirmed that the Andes strain of hantavirus — the only strain known to spread from person to person — is behind the outbreak.
While all passengers onboard the cruise have been taken care of by health authorities, the virus' long incubation period is a serious risk factor. Which means that even those asymptomatic can turn infectious 6-8 weeks later.
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