As discussed in another blog post, it is know that in Alzheimer’s disease, the brain loses its ability to uptake and use glucose. This decreased glucose utilization results in decrease energy (ATP) production, causing an energy deficit in the brain. It is believed that this energy deficit then increases the risk of neuronal dysfunction and cognitive decline. Specifically, it has been shown that patients with early Alzheimer’s disease have 20-30% less glucose uptake and utilization in certain areas of the brains compared to cognitively normal older adults. Research by Dr. Cunnane, has shown that the uptake and utilization of ketones is the same in brains of patients with Alzheimer’s disease compared to the brains of cognitively normal older adults. (Cunnane, 2016)
This research by Dr Cunnane shows that the even the areas of the Alzheimer’s brains that had decreased uptake of glucose had normal uptake of ketones. The implication of this is that the neurons themselves are not dead just not able to use glucose. The hope is that ketones can help improve cognition by improving this brain energy deficit. This was the basis of the KU Alzheimer’s Disease Ketogenic Diet study. The objection of the study was to see if by changing the fuel source from glucose to ketones thru the KD, would result in improvement of cognitive symptoms in patients with Alzheimer’s disease.
The KU Alzheimer’s Disease Ketogenic Diet Feasibility and Retention Trial
The KU Alzheimer’s Disease Ketogenic Diet Feasibility and Retention Trial, involved 15 patients with a diagnosis of mild Alzheimer’s disease. The 15 patients were placed on the KD and an additional triglyceride supplement for 3 months. The degree of ketosis was measured thru urine and plasma ketone levels. Cognitive function tests were assessed at baseline, at the end of the 3 months, and then a month later after back on a regular diet.
Out of the 15 patients, 5 were able to unable to achieve ketosis and dropped out of the study. The 10 that were able to get into ketosis and remain on the diet for 3 months, showed an improvement in cognitive function of 4.1 points on the Alzheimer’s Disease Assessment Scale-Cog (ADAS Cog) score. After returning back to a standard diet, the scores then dropped back down to their baselines values.
The author of the study, Dr. Swerdlow, was noted to say: “As far as Alzheimer’s studies go, a 4 point improvement in the ADAS Cog score is fairly robust.” “It suggests a meaningful improvement in cognition.” “It is greater than that seen in the cholinesterase inhibitors studies.” (Hughes, 2017)
Data from this study supports the need for further studies of KD in Alzheimer’s disease. The intervention was well tolerated without serious adverse event. The main limitation of the study was adhering to the KD. (Swerdlow, 2017) Dr. Swerdlow noted that the KD is not an easy diet to be on, and potentially an easier way to get ketones to the brain may be with supplements, which does not require such a strict low carbohydrate diet.