The bioenergetic changes induced by a ketogenic metabolism appear to be beneficial for neurodegenerative conditions. Promising research is being done on ketogenic diets for Alzheimer’s and Parkinson’s diseases, and a paper published recently in Frontiers in Neurology presents encouraging results from a proof-of-concept case study involving a subject with bulbar-onset amyotrophic lateral sclerosis (ALS) who followed a time-restricted ketogenic diet.
The subject was a 64-year-old man with a 21-month history of progressive, deteriorating bulbar-onset ALS. He followed a time-restricted ketogenic diet (TRKD) for the study duration of 18 months, and now, 45 months since symptom onset, he remains functionally independent and continues to follow the diet.
The TRKD called for two meals per day, each lasting up to an hour, with encouragement to eat to satiation and not restrict caloric intake. Water, tea, and coffee were permitted during the fasting hours and the diet was roughly 60% fat, 30% protein, 5% fiber, and 5% net carbohydrate by weight. Blood glucose and ketones were measured daily at bedtime. (Glucose was higher, and ketones lower, than expected based on his diet and the daily fasting. Researchers speculate that the ALS disease process itself may affect ketogenesis or ketone uptake and usage.)
The subject experienced improvements in depression, fatigue, and quality of life. In ALS-specific measures, he exhibited declines in physical function, maximal inspiratory pressure, and maximal expiratory pressure, but improvements in ALS-related function, forced expiratory volume, and forced vital capacity. Forced vital capacity has a predicted 2-3% decline per month in ALS patients, yet this subject improved from a baseline of 3.3 L to 4.33 L. Another assessment method – the Revised ALS Functional Rating Scale (ALSFRS-R) – has scores ranging from 0 to 48, with higher numbers indicating improved function. Based on the typical course of the disease, the subject’s score was predicted to decline from 42 at baseline to 24 over the 18-months study. Instead, it improved to 45. (The researchers noted, “Although ALSFRS-R score changes do not necessarily reflect improvement, and the specific tests of physical function declined at the final assessment, the fact that our patient's score did not decline over 18 months is potentially important.”)
This is just one case study, but it’s an exciting new frontier for research, which is particularly critical considering the lack of effective treatments for this condition.