The first time I seriously looked at the research on ketogenic nutrition and neurological disease was while writing the Parkinson's Alternative Approaches booklet — a project that started with my own family situation and became something much larger.
What I found was a body of evidence that is not yet mainstream but is more substantial than most people realise. The connection between ketones and brain health is not speculative. It is mechanistic, supported by human trials, and growing rapidly.
The Brain's Energy Problem in Neurological Disease
The brain is the most energy-intensive organ in the body. It accounts for roughly 20% of total energy consumption despite being 2% of body weight. Most of this energy, in a standard diet, comes from glucose.
In Alzheimer's disease, a consistent finding is reduced glucose metabolism in specific brain regions — particularly the hippocampus and cortex — often appearing decades before symptoms. This has led some researchers to describe Alzheimer's as "type 3 diabetes" — a condition of insulin resistance in the brain.
In Parkinson's disease, mitochondrial dysfunction in dopaminergic neurons is a central feature. These neurons have high energy demands and are particularly vulnerable when energy production is impaired.
The critical point: ketones bypass the glucose transport problem. They cross the blood-brain barrier through a different mechanism and can fuel neurons that can no longer efficiently use glucose.
The Evidence So Far
In Alzheimer's disease, the most publicised work includes studies showing that medium-chain triglycerides (MCTs) — which are rapidly converted to ketones — can produce measurable short-term improvements in cognition in some patients with early to moderate disease. Larger randomised trials are underway.
In Parkinson's disease, a pilot study by VanItallie et al. (2005) showed that five patients on a ketogenic diet for 28 days experienced significant reductions in tremor and other motor symptoms as measured by the Unified Parkinson's Disease Rating Scale. A small study, but a meaningful signal that larger trials are now following up on.
In epilepsy, the evidence is strongest and longest-established. The ketogenic diet has been used as a treatment for drug-resistant epilepsy since the 1920s. The mechanism is well-documented. This provides a validated proof of concept for keto's neurological effects that goes back over a century.
Why This Matters Beyond Disease
Neurological decline is not binary — healthy or diseased. It is a continuum. The metabolic dysfunction that characterises Alzheimer's and Parkinson's exists on a spectrum that begins decades before diagnosis.
This means the relevant question is not only "can keto help people with these conditions?" but also "can maintaining ketosis reduce the risk of developing them?" The epidemiological evidence is not yet definitive, but the mechanistic case — reduced inflammation, improved mitochondrial function, reduced oxidative stress, alternative fuel for insulin-resistant neurons — is coherent and plausible.
For Caregivers and Families
If you are caring for someone with Parkinson's or dementia, or have a family history that concerns you, the evidence available is sufficient to justify exploring a ketogenic or modified ketogenic diet as part of a broader management approach — with appropriate medical supervision for anyone on medication.
The Parkinson's Alternative Approaches booklet (currently available in German, English translation in progress) goes deeper into the specific protocols, drug interactions to be aware of, and practical implementation for people who may have difficulty with standard dietary changes.
The brain is not separate from the metabolism. What protects the body often protects the brain. The NKFB protocol was designed with both in mind.
