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.

Millions of people around the world undergo blood tests every year to measure LDL, commonly known as "bad" cholesterol. But researchers now suggest that this standard test may not always provide the most accurate picture of heart disease risk.

A new study from Northwestern Medicine found that a blood test measuring apolipoprotein B (ApoB) may be better than LDL cholesterol testing for identifying people who need more intensive treatment to reduce their risk of heart attacks and strokes.

The researchers also found that using ApoB to guide treatment decisions could prevent more cardiovascular events while remaining cost-effective for healthcare systems. The findings were published in the journal JAMA.

"We found that ApoB testing to intensify cholesterol-lowering medication would prevent more heart attacks and strokes than current practice, and that these health benefits were achieved at a cost that represents good value for US healthcare payers," said study lead author Ciaran Kohli-Lynch, Assistant Professor of Preventive Medicine in the Division of Epidemiology at Northwestern University Feinberg School of Medicine.

ApoB vs LDL: What's the Difference?

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

Doctors have traditionally relied on LDL ("bad") cholesterol and non-HDL cholesterol levels to assess heart disease risk and decide when patients should begin or intensify cholesterol-lowering treatment. While these tests provide useful information, researchers say they do not tell the whole story.

The difference lies in what the two tests measure:

• LDL cholesterol test: Measures the amount of LDL cholesterol in the blood.
• ApoB test: Measures the number of cholesterol-carrying particles—including LDL and other potentially harmful particles—that can enter artery walls and contribute to plaque buildup.

"Research strongly shows that apolipoprotein B (ApoB) is better at identifying who is at risk because it counts the total number of harmful particles in the blood," Kohli-Lynch said.

According to the researchers, the number of harmful particles may provide a more accurate measure of cardiovascular risk than LDL cholesterol levels alone.

What Is ApoB?

Read More: US Cardiologist Explains Why 2026 AHA Cholesterol Guidelines Recommend Starting Young

In a post on X, Dr. Sudhir, Senior Consultant Neurologist at the Institute of Neurosciences, Apollo Hospitals, Hyderabad, explained that ApoB is a protein found on potentially harmful cholesterol-carrying particles such as LDL and VLDL (very low-density lipoprotein).

"Think of ApoB as a count of the particles capable of entering artery walls and causing plaque. One ApoB is equal to one potentially harmful particle," he said.

Dr. Sudhir explained that two people can have the same LDL cholesterol level but very different numbers of cholesterol-carrying particles. The person with more particles will usually have a higher ApoB level and, potentially, a greater risk of cardiovascular disease.

He added that ApoB often provides a more accurate assessment of heart disease risk than LDL cholesterol alone.

Despite growing evidence supporting ApoB, the test is still not widely used in routine clinical practice because it generally requires an additional blood test beyond the standard cholesterol panel, increasing both cost and inconvenience.

"Our study asked: Is it worth spending extra money to use ApoB instead of LDL to guide treatment intensification?" Kohli-Lynch said.

Dr. Sudhir suggested that ApoB testing should be considered for:

• people with diabetes,
• prediabetes,
• metabolic syndrome,
• obesity,
• elevated triglycerides,
• strong family history of heart disease.

New Cholesterol Guidelines

Earlier this year, the American Heart Association and 10 other medical organisations released updated guidelines recommending that many people begin cholesterol-lowering therapy at younger ages.

"This means it is increasingly important to accurately identify who would benefit most from intensive treatment," Kohli-Lynch said.

The updated guidelines also recommend measuring ApoB, particularly in people with high triglycerides, diabetes or in situations where LDL cholesterol levels may underestimate the number of harmful cholesterol-carrying particles.

Do you often forget where you kept your keys or glasses and worry that it could be a sign of Alzheimer's disease? While many people become more forgetful with age, doctors say that occasional memory lapses are a normal part of ageing. Alzheimer's disease, however, causes a different pattern of decline that affects memory, thinking and the ability to function in everyday life.

HealthandMe spoke to two neurologists who explained how to tell the difference between normal age-related forgetfulness and the warning signs of Alzheimer's disease.

"Many people worry when they start becoming more forgetful with age. While some changes in memory and thinking are a natural part of growing older, Alzheimer's disease causes a different pattern of decline that affects everyday life," said Dr. Rajneesh Kummar, Vice Chairman & Unit Head, Neurology, Max Super Speciality Hospital, Dwarka.

Dr. Praveen Gupta, Chairman, MAIINS, Marengo Asia Hospitals, Gurugram, added, "Alzheimer's is not a normal part of ageing. It's a neurodegenerative disease that affects memory, thinking and how you function each day. Recognising the difference can help people get medical evaluation and treatment sooner."

Also read: India Gets Its First Alzheimer’s Drug: Know All About Eli Lilly’s Lormalzi

The experts advised that persistent memory concerns should not be ignored. If symptoms become more noticeable or begin affecting day-to-day functioning, a medical assessment can help identify the cause and guide appropriate treatment and support.

They outlined six key differences that can help distinguish normal ageing from Alzheimer's disease.

1. Occasional Forgetfulness vs Repeated Memory Loss

According to the doctors, it is common to occasionally misplace items, forget a name or an appointment, and remember the information later.

However, people with Alzheimer's disease may repeatedly forget recent events, conversations, appointments or newly learned information and may not recall them even after reminders.

2. Slower Thinking vs Difficulty With Everyday Tasks

Normal ageing may mean taking longer to learn new technology or complete routine tasks.

In Alzheimer's disease, people may struggle to manage bills, prepare meals, follow directions, learn to use a new phone or remember instructions given only moments earlier.

3. Misplacing Things vs Forgetting They Were Ever There

Occasionally losing keys or glasses is considered a normal part of ageing, and most people can usually retrace their steps and find them.

By contrast, people with Alzheimer's disease may not remember putting an item down or even recall recently getting or buying it.

Read More: Anti-Inflammatory Diet May Help Lower Dementia Risk, Even In Those Who Show Early Signs Of Alzheimer’s: Study

4. Temporary Confusion vs Disorientation

Older adults may occasionally lose track of the day or date but usually remember it shortly afterwards.

According to the doctors, Alzheimer's disease can cause confusion about time, dates and places. People may repeatedly ask the same questions or become disoriented, even in familiar surroundings.

5. Searching for Words vs Difficulty Communicating

Everyone experiences occasional "tip-of-the-tongue" moments.

With Alzheimer's disease, people may frequently lose their train of thought, repeat themselves, struggle to follow conversations or have difficulty finding the right words.

6. Remaining Independent vs Needing Increasing Support

The doctors said one of the biggest differences is that normal ageing generally does not prevent a person from living independently.

Alzheimer's disease, however, gradually affects a person's ability to carry out everyday activities, adapt to changes in routine and maintain self-care without assistance.

Bryan Johnson, the billionaire biohacker and longevity enthusiast, has been diagnosed with an incurable autoimmune disease called Autoimmune Gastritis (AIG).

Johnson is known for his radical longevity experiments, including measuring the biological age of his organs in an effort to reverse aging, injecting himself with ketamine, taking over 50 pills a day, undergoing fat transfers, and receiving blood transfusions from his teenage son.

In a recent post on X, he made the shocking announcement of his autoimmune conditions, which went undetected for years: Autoimmune Gastritis.

Calling it "bad news," Johnson wrote: "I have an autoimmune disease. My stomach is eating itself."

"2-5 per cent of people have this, too. Likely more, because it hides," he added.

According to Johnson, his stomach had been attacking itself without causing noticeable symptoms. The condition was only discovered in May.

Also read: Bryan Johnson Blames Sugary Cereals, Soda and Stress for His Autoimmune Disease; Shares Treatment Plan

The Early Warning Sign: Low Ferritin

Autoimmune Gastritis, a condition in which the immune system attacks the stomach's acid-producing cells, also impairs the absorption of iron and vitamin B12.

Johnson said one of the earliest signs of the condition was persistently low ferritin levels over the past 11 years despite not having anemia.

"We continually tried to raise my iron levels with food and supplementation, but nothing would work."

He said he followed a plant-based diet, trained intensely, used a sauna and hyperbaric oxygen therapy, and took iron supplements, yet his iron levels remained low.

Ferritin stores the body's iron. Iron is essential for transporting oxygen and producing energy, and low iron levels can lead to fatigue, weakness, and dizziness.

Johnson said autoimmune gastritis is difficult to diagnose because its earliest clue is often overlooked.

"The earliest clue, low ferritin, is the one standard medicine waves through. Low iron stores get normalized and rarely investigated at all when anemia hasn't shown up yet. That blind spot is what hid mine for a decade."

While initially it wasn't clear why his iron levels were continuously dipping, after further testing, Johnson's team identified three interconnected issues.

Read More: Bryan Johnson Battles Autoimmune Gastritis: Which Parts Of His Longevity Guide Are Actually Worth Copying?

Autoimmune Gastritis was preventing normal iron absorption by damaging the stomach cells that produce acid. He also discovered autoimmune thyroid disease.

"The iron deficiency, the autoimmune gastritis driving it, and the autoimmune thyroid disease alongside it. Iron and thyroid feed each other both ways; low iron impairs the conversion of thyroid hormone into its active form, and an underactive thyroid impairs how the body uses iron," Johnson explained.

Iron Deficiency May Be More Common Than Many Realize

According to research published in JAMA Network Open, about one in four Americans may have inadequate iron intake or absorption.

As per the study of more than 8,000 Americans, 14 per cent of adults had absolute iron deficiency, reflecting depleted iron stores.

Even after excluding common causes such as anemia, pregnancy, heart failure, and chronic kidney disease, 11 per cent remained iron deficient. Another 15 per cent had functional iron deficiency, where iron levels appear normal but the body cannot use the mineral effectively.

How Bryan Johnson Is Managing The Condition

Since receiving the diagnosis, Johnson has begun iron infusions, which deliver a full dose of iron in a single treatment.

He said his team will continue routine monitoring of his ferritin and iron levels.

Johnson ended his post with a warning that hidden health conditions can go unnoticed for years.

"You too may have a lurking health issue that is undiagnosed and could increase in severity from unhealthy life choices, without your knowing… A gentle nudge that minding your health, no matter your situation in life, is a good decision-making."