Type 3 diabetes is a term used to describe the link between certain features of diabetes and Alzheimer’s disease. While it’s not an official form of diabetes, research since the early 2000s shows that the effects of insulin resistance on the brain may contribute to cognitive decline.
More research is needed to understand how one condition contributes to the other, but it’s clear that reducing your risk of developing diabetes is important to overall cognitive health. A diet like keto that supports both your metabolic and cognitive health can be a positive first step.
Understanding The Connection
Research supporting a connection between diabetes, particularly type 2 diabetes, and a higher risk of developing Alzheimer’s focuses on the metabolic syndrome’s effects on brain cells. (1) Insulin resistance, a hallmark of type 2 diabetes, can affect their ability to produce glucose.
This leads to energy deficits that get in the way of cellular functions essential to memory and cognition, especially as we age. Your brain’s inability to use insulin efficiently can then directly contribute to neurodegeneration. (2)
Diabetes and Alzheimer’s have even more in common. On top of insulin-like growth factor dysfunction, people with type 2 diabetes also tend to have higher levels of inflammation that worsen the effects of APOE4. (3)
APOE4 is a variant of the APOE gene linked to lipid metabolism. While APOE2 provides protective effects against plaque formation in the early stages of Alzheimer’s, APOE4 seems to block insulin receptors and cause damage to brain cells. (4)
A diabetes diagnosis doesn’t guarantee you’ll develop Alzheimer’s down the line, but studies suggest that people with diabetes are up to twice as likely to develop the condition. (5) Managing your blood glucose through a healthy diet and other lifestyle changes can help mitigate that risk.
Insulin and Blood Sugar
Insulin resistance inhibits the brain’s ability to use glucose, leading to energy shortages that impair cognitive functions. It bears repeating that this insulin disruption can increase inflammation and oxidative stress and accelerate beta-amyloid plaque formation, a marker of Alzheimer’s. (6)
Elevated blood sugar can worsen these effects. While insulin resistance doesn’t directly cause Alzheimer’s, it’s a significant risk factor. (7) Blood sugar management and improving your insulin sensitivity are both essential for brain health.
How Keto Can Help
The ketogenic diet is linked to protective effects against both Alzheimer’s and diabetes thanks to the effects of ketosis. Ketosis, a metabolic state where your body uses ketones for energy over glucose and carbs, serves as an alternative energy source for your brain.
This change can improve blood sugar control, reduce insulin resistance, and lower inflammation, all positive news for those at risk of developing diabetes, vascular dementia, and Alzheimer’s.
Improved Insulin Sensitivity
The keto diet is popular with diabetic patients for its effects on insulin resistance. As your body adapts to using fat and ketones for energy, blood sugar levels decline, and insulin sensitivity improves. (8)
Improved insulin sensitivity reduces blood sugar spikes, lowers inflammation, and decreases oxidative stress. This is a benefit to anyone at risk for diabetes and patients worried about the condition’s effects on their Alzheimer’s risk.
Stable Energy Levels
When you’re dealing with insulin dysfunction, glucose stays in your bloodstream instead of traveling to your cells for energy. This means more than chronic fatigue.
Over time, it can increase your risk of metabolic conditions like diabetes and leave your brain cells without a consistent energy source. That can put you at risk for neurogenerative conditions like Alzheimer’s. (9)
Following a keto diet improves energy levels by promoting stable blood sugar levels and reducing sugar crashes linked to excess glucose and carbs. Ketones are a steady energy supply that keeps both your body and your brain functioning at optimal levels.
Many people on keto report feeling more focused and alert after a few weeks on the diet. This is likely the effect of ketones crossing the blood-brain barrier to fuel cognitive processes more efficiently and sustainably, potentially reducing your risk of neurodegeneration.
Our Ketone Testing Strips are an easy way to see whether your diet is on the track toward optimizing the effects of ketosis.
Reduced Inflammation
Chronic inflammation increases your risk of cardiovascular disease, hypertension, diabetes, cancer, arthritis, and neurogenerative diseases like Alzheimer’s and Parkinson’s. Any steps you can take to reduce inflammation in the body are essential to overall health.
The keto diet reduces inflammation by decreasing blood sugar fluctuations, boosting your body’s response to oxidative stress, and enhancing mitochondrial health. (10 These benefits combined lower your risk of not only Alzheimer’s and diabetes but all of the conditions mentioned above.
Weight Management
Obesity increases your risk of both type 2 diabetes and Alzheimer’s. The research isn’t clear why, but obesity is associated with high blood pressure, high cholesterol, and inflammation. All three contribute to the breakdown of blood vessels in the brain and insulin resistance. (11)
Keto supports sustainable weight management and reduces obesity risk by supporting a more efficient metabolism, boosting energy, and helping you feel more full. The diet shifts your body’s metabolism to burn fat for fuel, helping in weight loss and minimizing fat storage long-term. (12)
Potential to Lower Oxidative Stress
High glucose levels can increase the production of reactive oxygen species (ROS) that contribute to prediabetes and cause cell damage.
Shifting your body’s primary energy source from glucose to ketones reduces oxidative stress by improving mitochondrial function and limiting damage from disease-causing free radicals. (13)
Lowering your carb intake on keto also stabilizes high blood sugar, improves insulin signaling, and decreases damage to blood vessels affected by high glucose. (14) This may lead to protective effects against brain cell degeneration and reduce your risk of Alzheimer’s.
Neuroprotective Effects
Your brain needs steady blood flow and a steady energy source to function. Inducing ketosis by following a keto diet or intermittent fasting provides an alternative source of energy that is more stable than what you get from glucose.
This means your brain cells and neurons are better able to work how they should, potentially slowing the progression of Alzheimer’s or reducing your risk of dementia overall.
Ketones also help stabilize nervous system function and reduce excitotoxicity, a process where nerve cells are damaged by overstimulation from neurotransmitters like glutamate.
This process is implicated in neurodegenerative diseases like Alzheimer’s. (15) Chronic stress, sleep deprivation, and a bad diet can all make it worse.
Note: Ketosis Is Not the Same as Ketoacidosis
It’s important to distinguish ketosis from ketoacidosis, especially in the context of diabetes. Ketosis is a safe metabolic state achieved through a ketogenic diet that produces ketones at manageable levels.
Ketoacidosis, or diabetic ketoacidosis (DKA), is a dangerous complication found mainly in type 1 diabetes patients where blood ketone levels rise and stay above 300 mg/dL. (16) The cause is low levels of insulin due to illness or missed insulin shots.
Without insulin to regulate glucose, ketone levels spike, acidifying the blood and posing severe health risks. DKA is a medical emergency requiring immediate attention, not a side effect of ketosis.
Can Type 3 Diabetes Be Cured?
Type 3 diabetes isn’t an official diagnosis, but there is no cure for Alzheimer’s disease. (17) Despite the link between diabetes and aging-related dementia, it’s also important to note that living with diabetes doesn’t mean you’ll develop Alzheimer’s down the line.
Alzheimer’s is complex. Your genetics, lifestyle, and environmental factors all matter when it comes to analyzing your risk. Since neuroscience hasn’t come up with one direct cause, preventing Alzheimer’s completely may not be possible at this time.
That said, you can reduce your risk of the development of Alzheimer’s down the line by taking steps to reduce chronic stress, staying mentally active, and following a healthy diet.
The Takeaway
A ketogenic diet can be a powerful tool in managing insulin resistance that could contribute to Alzheimer’s down the line. Ketosis is good for your brain’s energy supply, reduces oxidative stress, and lowers inflammation.
All of these benefits have the potential to slow cognitive decline and keep brain tissues healthy and active enough to fight back against neurodegenerative conditions in older adults.
As we learn more about where type 3 diabetes fits in the landscape of healthier aging, diets like keto will continue to play a role in healthy cognition.
If you’re overwhelmed by the idea of starting a new diet, our free Keto Calculator can help you identify the macro combination you need to meet your goals.
FAQ
What are the symptoms of Type 3 diabetes?
The symptoms of type 3 diabetes overlap with symptoms of Alzheimer’s disease, but it’s important to note that type 3 diabetes is not an official diagnosis.
Symptoms of Alzheimer’s include:
- Memory loss and confusion
- Difficulty completing tasks or finding words
- Impaired decision-making
- Mood changes (e.g. increased irritability and anxiety)
- Disorientation, even in familiar spaces
- Trouble with visual or spatial relationships
- Declines in attention span
- Social withdrawal
What is Type 3c diabetes mellitus?
Type 3c diabetes mellitus (T3cDM), or pancreatogenic diabetes, happens when the pancreas stops producing enough insulin in islets of beta cells. Surgeries, chronic pancreatitis, and cystic fibrosis are common causes of the condition.
T3cDM is unrelated to the theory of type 3 diabetes. While not as common as other types of diabetes (type 1, type 2, and gestational diabetes), it’s often misdiagnosed as type 2 diabetes.
How do I test for type 3 diabetes?
There is no specific test for type 3 diabetes, as it isn’t an official medical diagnosis. Testing for Alzheimer’s is a complex process that includes a neurological examination, gathering family history, and a series of imaging scans that look for abnormalities.
If your healthcare provider suspects type 2 diabetes in addition to neurological symptoms, they may order a series of blood sugar tests, including the glycated hemoglobin (A1C) test, which looks at average blood sugar levels over time.
How is type 3 diabetes diagnosed?
Type 3 diabetes is not an official diagnosis. Diagnosing Alzheimer’s involves cognitive assessments, neuroimaging, and ruling out other potential causes of dementia. Neurology panels can also show the disease progression in patients already showing signs of cognitive impairment.
Treatment options like dietary changes and cognitive therapies focus on slowing cognitive decline. Prescribed medications may include acetylcholinesterase inhibitors and peptides to improve cognitive function. Research is mixed about the protective effects of metformin, a diabetes medication.