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.

What is Type 3 Diabetes?

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.

Symptoms of Type 3 Diabetes

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.

Causes of Type 3 Diabetes

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:

1. Insulin Resistance

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.

2. Type 2 Diabetes

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.

3. Environmental and Lifestyle Factors

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.

Treatments for Type 3 Diabetes

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.

Can Type 3 Diabetes Be Prevented?

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.

India is facing a growing burden of non-communicable diseases (NCDs), with hypertension and diabetes among the major health concerns.

Experts warned that the risk of both conditions rises after 40, often without noticeable symptoms. Increasing age, weight gain, reduced physical activity, stress, dietary habits, and metabolic changes can all contribute to the risk.

Having hypertension and diabetes together is particularly concerning, as their coexistence can increase the risk of heart disease, stroke, kidney damage, retinopathy, and other complications.

Why Risk Rises After 40?

Dr. Santosh Gupta, Associate Director - CTVS, Paras Health Udaipur, told HealthandMe that several factors contribute to the rising risk after 40.

“After the age of 40, the risk of hypertension and diabetes increases due to factors such as changes in metabolism, reduced physical activity, weight gain, stress and dietary habits. What makes both conditions particularly concerning is that they can develop silently, without noticeable symptoms, while gradually affecting vital organs,” he said.

He added that uncontrolled hypertension can damage the heart, brain, kidneys, and blood vessels, while diabetes can affect the kidneys, eyes, nerves, and cardiovascular system.

"When both conditions occur together, the risk of heart disease, stroke and kidney complications becomes even higher,” Dr. Gupta added.

Because both conditions can remain silent for years, people may have high blood pressure or blood sugar without knowing it.

Also read: Breastfeeding Can Help Reduce Mothers' Risk of Type 2 Diabetes, Breast Cancer and More

Hypertension And Diabetes Often Coexist

A recent hospital-based analysis found that hypertension and diabetes frequently occur together, with their coexistence rising sharply from around age 40 among Indians.

The study, conducted by the Department of Clinical Research and Preventive Health Program at Max Healthcare, analyzed health records of more than 56,000 adults who underwent preventive health check-ups between January 2021 and December 2024.

Nearly 5% of adults had both conditions. Their coexistence increased rapidly from around 40, continued rising until approximately 58 and gradually reached nearly 17% by around age 70.

People with diabetes were nearly four times more likely to have hypertension, while those with hypertension were about 2.5 times more likely to have diabetes.

Dr. Abhaya Indrayan, Biostatistics Consultant, Max Healthcare, said the findings support screening for both conditions rather than assessing them separately.

Why Screening After 40 Matters

Read More: Confused By Your Cholesterol Report? Here's What LDL And ApoB Really Mean

Experts said that preventive healthcare should go beyond checking for individual diseases. Adults over 40 should routinely assess key cardiometabolic risk factors, including blood pressure and blood sugar.

Screening can help detect hypertension, diabetes or prediabetes early, when lifestyle changes and treatment can help prevent or delay complications.

“This is why regular screening after 40 is important, even for individuals who feel completely healthy. A routine blood pressure check, fasting blood glucose or HbA1c test can help identify hypertension, diabetes or prediabetes at an early stage, when timely lifestyle changes and medical intervention can prevent or delay complications,” Dr. Gupta said.

“Screening should not be viewed only as a diagnostic exercise; it is an opportunity to understand one’s health risks and take corrective measures before the disease begins to cause irreversible organ damage,” he added.

How To Lower The Risk

Preventive care also involves addressing modifiable risk factors. Regular physical activity, maintaining a healthy weight, limiting salt, sugar and highly processed foods, getting adequate sleep and avoiding tobacco can help lower the long-term risk.

For those already diagnosed with hypertension or diabetes, regular monitoring and adherence to prescribed treatment are important to reduce the risk of complications.

With the risk of both conditions rising after 40, experts recommend making routine health checks part of regular healthcare—even when there are no obvious symptoms.

Amid the ongoing monsoon season, Delhi-NCR is seeing a rise in H1N1 influenza cases, with Delhi reporting 1,344 cases so far this season.

The figure is nearly six times higher than the 229 H1N1 cases recorded during the same period last year, The Times of India reported.

According to health officials, Delhi recorded around 4,000 influenza cases last year, most of them caused by H3N2. This year, H1N1 is the dominant strain. Both H1N1 and H3N2 are subtypes of Influenza A and spread mainly through respiratory droplets.

What Is H1N1 and Why Is Testing Important?

H1N1 is a subtype of Influenza A and can cause sudden fever, cough, sore throat, headache, body aches and fatigue. These symptoms can overlap with those of other seasonal influenza strains, COVID-19 and respiratory syncytial virus (RSV), making it difficult to identify the infection based on symptoms alone.

Dr Aijaz Ilmi, Senior Consultant – Metabolic Diseases, Pacific OneHealth Hospital, told HealthandMe that testing is particularly important when fever or respiratory symptoms persist or worsen, especially among older adults, young children, pregnant women and people with diabetes, obesity, heart or lung disease, or compromised immunity.

“With the current rise in H1N1 cases in Delhi, we are also seeing other seasonal respiratory infections, including Influenza A and B, COVID-19, RSV and other respiratory viruses. At the same time, the monsoon season brings an increased risk of mosquito-borne illnesses such as dengue.

“The key message is, don’t panic, but don’t dismiss a persistent fever as ‘just a viral’. Early recognition is particularly important in vulnerable individuals.”

H1N1 vs Other Respiratory Infections: How Are They Different?

H1N1 can be difficult to distinguish from other respiratory infections because many of them cause similar symptoms.

• H1N1 and other seasonal influenza strains: Both can cause sudden fever, cough, sore throat, headache, body aches and fatigue. Symptoms alone generally cannot determine whether the infection is H1N1 or another influenza strain.

• COVID-19: COVID-19 can cause fever, cough, sore throat, congestion and fatigue. Some people may also experience changes in or loss of taste or smell, while gastrointestinal symptoms can occur.
• RSV: RSV commonly causes a runny nose, cough and wheezing. It can be more severe in infants, older adults and people with certain underlying conditions. In young children, it can cause bronchiolitis and breathing difficulties.
• Dengue: During the monsoon, dengue can also cause fever, headache, body aches and fatigue, which may initially resemble a viral respiratory infection. However, dengue is spread by mosquitoes rather than respiratory droplets and does not typically cause cough or sore throat.

How Can H1N1 and Other Infections Be Prevented?

Dr Sharwari Sudhir Dabhade, Consultant - Internal Medicine, Diabetology & Endocrinology, Madhukar Rainbow Children's Hospital, told HealthandMe that prevention should focus on reducing exposure and maintaining good hygiene. Other measures to reduce transmission include:

• Washing hands frequently.
• Covering mouth and nose while coughing or sneezing.
• Maintaining good indoor ventilation.
• Avoiding crowded or poorly ventilated places when respiratory infections are circulating.
• If you have respiratory symptoms, limit close contact with others and wear a mask.
• Getting vaccinated against influenza, particularly if you are an older adult, young child or have an underlying health condition.
• Prevent mosquito breeding and take precautions to avoid mosquito bites to reduce risk of dengue.

When Should You Seek Medical Help?

Most viral respiratory infections recover with supportive care. However, should seek prompt immediate medical assessment in cases of

• breathlessness
• persistent high fever,
• chest pain,
• confusion,
• dehydration,
• falling oxygen saturation
• significant worsening of weakness.

People with inflammatory bowel disease (IBD) may face a higher risk of depression, anxiety and other psychiatric disorders years before they are diagnosed with the gut condition, a new study has discovered.

The study, published in Clinical Gastroenterology and Hepatology, found that the risk of psychiatric disorders began rising two to three years before an IBD diagnosis, peaked shortly after diagnosis and remained elevated for as long as a decade.

Researchers from Karolinska Institutet and other Swedish institutions analysed data from 43,862 people with IBD, comparing them with nearly 179,000 individuals from the general population and more than 26,000 IBD-free full siblings.

The sibling comparison was key as it helped researchers examine whether shared genetic or early-life environmental factors could explain any association.

Risk Of Mental Health Issues Increase Before IBD Diagnosis

Also read: Monsoon Gut Health: Addressing The Rise In Rotavirus And Viral Gastroenteritis Cases

The study found that the risk of developing any mental health disorder was already 15% higher two years before IBD diagnosis. It increased further around the time of diagnosis, reaching a roughly 50% higher risk within the first six months.

Although the risk reduced afterwards, it remained about 19% higher even 10 years after diagnosis. Major depressive disorder, anxiety disorders and substance misuse accounted for much of the increase.

Antidepressant and anti-anxiety medication use also began rising around a year before the IBD diagnosis.

Researchers called for mental health screening to begin early, including during the initial gastroenterology evaluation.

“It is time to actively manage psychiatric conditions in patients with IBD,” said Jiangwei Sun, PhD, the study’s lead author.

Why Depression And Anxiety Appear Before IBD Is Diagnosed?

Also read: Following A Western Diet? Changes In Your Gut Bacteria Could Increase Colon Cancer Risk

IBD includes Crohn’s disease and ulcerative colitis, autoimmune conditions that cause inflammation in the digestive tract.

One possible explanation is the gut-brain axis, the two-way communication system connecting the digestive system and brain.

Inflammation, changes in gut bacteria and abnormal immune activity may affect brain function and overall mood. At the same time, stress and psychological distress can affect the gastrointestinal symptoms.

But researchers caution that the study merely shows an association, not proof that IBD directly causes depression or anxiety.

Some people may experience subtle or unexplained gastrointestinal symptoms before receiving an official diagnosis, while the uncertainty and disruption caused by chronic symptoms could also affect mental health.

Mounting Evidence

The findings follow previous research that shows psychiatric symptoms can surface before the patient is diagnosed with IBD.

A 2023 study examining longitudinal health records found that anxiety and depression occurred more frequently among people who were later diagnosed with IBD.

In a 2024 systematic review and meta-analysis, it was observed that patients with a history of depression may have a small-to-moderate increased risk of subsequently developing IBD, suggesting that the relationship between the gut and mental health could work in both directions.

The new findings therefore signal that mental health symptoms may sometimes arrive years before IBD itself is formally diagnosed in patients.

For doctors, researchers say this highlights the need to treat IBD as more than a digestive disease, with psychological support and screening considered part of long-term care.