The brain’s main fuel source is glucose. However, it has been shown that the brains of people who have Alzheimer dementia (AD) are not able to utilize glucose as well as normal people. When there is not enough glucose to meet its metabolic needs, the neurons that work the hardest, i.e. those involved with memory and cognition are the first ones to be compromised and thus show impairment. So the question is: is there another fuel that the brain can use?
The answer luckily is yes! Ketone bodies (KB) or ketones are another fuel source for the brain and the body. Acetoacetate and Beta-hydroxybutyrate are collectively known as ketone bodies (KB). KB are normal metabolites that are manufactured by the liver as an alternative fuel for the body and the brain when dietary sources of carbohydrates are in short supply, a process called ketosis. Ketone bodies can be produced in healthy individuals either during times of fasting or by eating a ketogenic diet. The ketogenic diet was first introduced, over 80 years ago, as a dietary treatment of uncontrolled epilepsy in children. The ketogenic diet is diet consisting of high amounts of fat and low amounts of carbohydrates. Other ways of producing ketones nutritionally are by eating high amounts of medium chain triglycerides (MCTG) such as coconut oil repetitively throughout the day.
When ketones are available they are a better fuel source for the brain in patients with AD for several reasons. First of all, ketones do not need insulin for uptake into the cell, so it is easier for the brain to get this fuel source compared to glucose. This decrease usage of glucose is visible on brain PET scans, which look at the uptake of glucose. In patients with early AD, there is a 14% overall decrease in the uptake of glucose compared to normal controls. In contrast, when this same patient is placed in brain PET scans looking at the uptake of ketones, the uptake is the same both in the patients with early AD and normal controls.
Other possible theories on why ketones are a better source of fuel for patients with AD is that they are a more efficient source of energy. First of all, ketones produce more energy (ATP) compared to glucose. Secondly, the mitochondria, the cells that produce the body’s energy, are believed to be impaired in patients with AD. Ketones, however, are able to bypass the blocked site of the energy pathway, the Krebs cycle, in the mitochondria. This allows the mitochondria to produce energy more efficiently when it is fueled by ketones.
There have been several published clinical studies looking at the effects of ketosis in patients with mild cognitive impairment and AD. The results have shown improved cognitive performance in patients who are in ketosis either from eating a ketogenic diet or from a diet consisting of a very high dose of MCTG oils (20- 70 g/day). This improvement in memory was positively correlated the urinary ketone levels, i.e. the higher the level of ketones in the body, the better the cognitive effect.
Even more exciting than the fact that the ketogenic diet has been shown to help memory in people with AD, is that there is also evidence that being in ketosis might also have some disease-modifying benefits in AD. In mouse models of AD, a ketogenic diet has been shown to actually improve the pathology associated with AD. Specifically, the mouse brains were found to have less beta-amyloid formation and less phosphorylated tau protein formation, the neuropathology associated with AD. Ketones have also been shown to have a neuroprotective effect on the hippocampal neurons from both glutamate and amyloid beta toxicity. The hippocampi in rats that are fed a ketogenic diet have also had an increasing amount of mitochondria. The neuroprotective effect thus may result from enhanced energy reserves, which improves the ability of the neurons to resist metabolic challenges. Another possibility is that ketone metabolism as compared to glucose metabolism generates less free radicals and lower oxidative stress, thus resulting in improved antioxidant capacity, decrease CNS inflammation, and thus less cell death.
There are potentially 2 problems associated with the ketogenic diet. 1) It is very difficult to adhere to, especially in people who have dementia, who are not self-motivated to stick with the diet. 2) Eating a high carbohydrate meal while on the ketogenic diet would potentially throw the person out of therapeutic ketosis and it may take a day or two to get back in, thus taking several days before seeing any benefits again. Up until now the only other alternative to the ketogenic diet to produce therapeutic ketosis is the repetitive ingestion of high does of MCTG. The problem with it is: the doses high enough to produce therapeutic ketosis are often associated with significant GI side effects. Additionally, the taste of MCTG is often difficult to swallow.
Luckily now there is a better way. There is a now a ketone supplement available to the public. This supplement, which is a proprietary blend of ketone mineral salts, puts your body into a state of therapeutic ketosis within 60 minutes of drinking it without having to be on a strict ketogenic diet.
Now, this ketone supplement is not an approved treatment by the FDA for treatment of AD or any other disease for that matter. However, I am so convinced, based on what the research suggests on what the Alzheimer’s brain needs to function at its optimal level. Along with what the potential benefits of being in the state of ketosis offers, including how it could work for the Alzheimer’s brain that I personally drink it myself and have also recommended it to my parents. Since there is no known cure for AD or proven treatment yet available if something as simple as drinking this supplement twice a day would help with your memory would you give it a try?
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