They say Alzheimer's may be prevented by following a set of five protocols.
Jenkins says it is one of the biggest medical breakthroughs in 30 years.
Okuno and Jenkins run their online consulting programme that uses what is known as the Bredesen method to prevent Alzheimer's, from their Makorori home.
They have examples of clients, one in Gisborne and one in Christchurch, whose cognitive tests, and their symptoms, improved after a diagnosis of cognitive decline and after following the protocols.
Critics claim it is a scam.
But Jenkins says it has just not been accepted by mainstream medical professionals “yet”.
These protocols are at an intersection of ideas where mainstream medical professionals haven't quite come to the party. Jenkins says the science backs it and it is only a matter of time before the programme gets the controlled trials required for mainstream adoption.
Jenkins hopes it is something he lives to see.
One Gisborne GP spoke under anonymity about the successful case in this region.
“I was very interested to observe that following a diagnosis of early Alzheimer's, my patient remained stable in his cognition for several years while adhering to the Bredesen protocol.”
Jenkins is better known for his founding role in Surf Aid international — giving the people who live in poverty-stricken but world-renowned remote surf spots a hand up not a hand out. His model for aid work is still being used today.
He got his medical degree at Otago School of Medicine in the ‘80s, then ran a large rural practice before entering medical education at Auckland Medical School.
His focus on Alzheimer's is personal. About seven-and-a-half years ago his mother Janet Jenkins was diagnosed with it.
One of the first indications was her new confusion with how to deal with her bills and finances — a common early sign.
His mother was 85 when she was diagnosed. Until then she had been living happily and independently in a lifestyle village. She was being given a concoction of pills, which led to her doctor son telling her, “You and me, we are going to the doctor.”
He struggled with the concept that “nothing can be done”.
But this wasn't some desperate son's last push for his mother, who is now 93 and was one of the first people Dave tried the Bredesen approach with.
The diet side was problematic as rest home kitchens don't take meal orders.
Jenkins says he and Okuno would like to partner with western doctors so there was a team approach to people who have this diagnosis.
For example, if a 50-year-old has a stroke now, the standard of care is to have a team approach with medical doctors, a neurologist and a physiotherapist.
A similar approach with a diagnosis of cognitive decline would have the best outcome with a team helping the patient that includes medical doctors like a neurologist, labwork to determine the underlying causes of cognitive decline, an occupational therapist to help with cognitive training, education on nutrition, exercise, and lifestyle and a coach to help implement the lifestyle approaches.
It is about working together to help those who are experiencing cognitive decline — which is where people's memory becomes so noticeably bad they eventually go and see a doctor.
The doctor may suggest the Mini-ACE which is a 30 question cognitive test. A score of 27 or less shows mild cognitive impairment (MCI) and the possibility of being on the path to Alzheimer's.
What the Bredesen approach recommends comes under the acronym of BASES - which stands for Brain work, Activity, Sleep and Stress, Eating, and Supplements.
Brain work includes brain training — there is even a helmet with red lights used in some cases.
Activity means the whole she-bang -- aerobics, strength, balance and flexibility.
Sleep and stress were big ones, said Okuno. Optimise your sleep for a good eight hours and ensure you do not have sleep apnea, which results in reduced oxygen to the brain.
Reduce stress, try meditation.
Eating a high fibre, high vegetable and high antioxidant diet that is low in carbohydrates keeps the brain healthy.
Nutritionist Okuno recommends a keto-tarian diet —largely plant-based, with quality protein such as wild caught fish, little meat, but very low carbs and sugar (if any).
Meals include lots of vegetables, and no dairy or grains.
As for the five plus a day rule? Okuno says increase that to nine vegetable servings a day (a serving being half a cup) and include lots of green and colourful vegetables.
Supplements vary depending on underlying deficiencies, but B12 and sorting out a low thyroid are two examples of important assessments which can have excellent consequences in some cases, said Jenkins.
Vitamin D is important and getting it from the sun (safely) is the best source, but others include from fatty fish like sardines or anchovies.
In 2016 the couple became certified Bredesen Protocol practitioners. They are also the only co-authors outside the US of a published study of 100 cases of the reversal of cognitive decline.
Out of those 100 case studies, 10 are their clients from Australia or New Zealand.
Jenkins is no longer practising as a registered doctor in New Zealand but acts as a technical consultant helping clients coordinate their strategy for cognitive decline.
Their online platform means they can help more people, wherever they are in the world.
For the past 15 years they have lived in Bali, Indonesia due to Dave's SurfAid work, but since April have been based at Makorori to see the pandemic out. But they will eventually return to Bali.
In any conversation about Alzheimer's words like perturbations, synapses and amyloid beta are used.
Words not many of us know the meaning of.
To try to put it simply, Jenkins (with Okuno as a translator between medical speak and all other speak) says, “There is a switch in the brain”.
He also says that any organ in the human body that gets damaged will try to repair itself.
Post-mortems of some people with Alzheimer's have found a build-up in the brain of fungi, bacteria, and viruses.
They have been allowed to congregate because that “switch” isn't being flicked for the body's normal immune response to fight them.
The build-up of the bad stuff causes a degeneration of the brain, and the connections between brain cells don't fire.
Jenkins calls it a slow, cold war in the brain.
So what flips the switch?
“The bad news is there are dozens of things that can contribute, and most patients have at least 10.
Infections, herpes simplex virus, toxins like mercury, or mycotoxins (mould), a leaky gut, diabetes or pre-diabetes — many of which can come from either the environment or a genetic background.
The good news, says Jenkins, is virtually every single one of these is treatable.
But there is no perfect drug or silver bullet.
Jenkins says the Bredesen approach is not one pill a day but a personalised precision programme based on underlying causes identified through testing with the patient's doctor.
Jenkins and team spend around 100 hours on each client over 12 months.
Each contributing factor to their cognitive decline is looked at, such as thyroid, levels of B and D vitamins, and hormone levels.
They are clear that this is not a cure. The programme can be refined over time, with annual testing, and those who go off the program tend to have their symptoms return.
Their clients come from a range of backgrounds. Some have a family history of the disease and are scared they are going to get it.
Early diagnosis is critical. Case studies of patients following the Bredesen Protocol approach for life, show a high degree of stabilisation or improvement, say Jenkins and Okuno.
Although these are early days, the first participants who started and stayed on the protocol are still doing well nine years on, says Jenkins.