The Ketogenic Diet Revisited: Beyond Ketones

The Ketogenic Diet in the Prevention of Migraines in the Elderly

Migraines display atypical age dependence, as the peak of their prevalence occurs between the ages of 20-40 years. With age, headache attacks occur less frequently and are characterized by a lower amplitude. However, both diagnosis and therapy of migraines in the elderly are challenging due to multiple comorbidities and polypharmacy. Dietary components and eating habits are migraine triggers; therefore, nutrition is a main target in migraine prevention. Several kinds of diets were proposed to prevent migraines, but none are commonly accepted due to inconsistent results obtained in different studies. The ketogenic diet is featured by very low-carbohydrate and high-fat contents. It may replace glucose with ketone bodies as the primary source of energy production. The ketogenic diet and the actions of ketone bodies are considered beneficial in several aspects of health, including migraine prevention, but studies on the ketogenic diet in migraines are not standardized and poorly evidenced. Apart from papers claiming beneficial effects of the ketogenic diet in migraines, several studies have reported that increased levels of ketone bodies may be associated with all-cause and incident heart failure mortality in older adults and are supported by research on mice showing that the ketogenic diets and diet supplementation with a human ketone body precursor may cause life span shortening. Therefore, despite reports showing a beneficial effect of the ketogenic diet in migraines, such a diet requires further studies, including clinical trials, to verify whether it should be recommended in older adults with migraines.

Stress biomarkers in adult patients with drug-resistant epilepsy on a modified Atkins diet: A prospective study

OBJECTIVE

Ketogenic diets like the modified Atkins diet (MAD) are increasingly used in patients with refractory epilepsy. For epilepsy patients, stress is a well-known seizure-precipitating factor. New possibilities for measuring biomarkers of stress are now available. The purpose of this study was to investigate the impact of MAD on endocrine stress biomarkers.

METHODS

Forty-nine patients with drug-resistant epilepsy were investigated at baseline and after 12 weeks on MAD. Cortisol and cortisol-binding globulin (CBG) were measured and free cortisol index (FCI) calculated. We also measured metanephrine, normetanephrine, and methoxytyramine, all markers of epinephrine, norepinephrine, and dopamine, respectively. Changes were analyzed according to sex and antiseizure medications. The different markers at baseline and after 12 weeks of MAD treatment were correlated with seizure frequency and weight loss, respectively.

RESULTS

The change in total cortisol was modest after 12 weeks on the diet (from 432.9 nmol/L (403.1-462.7)) to 422.6 nmol/L (384.6-461.0), P = 0.6). FCI was reduced (from 0.39 (0.36-0.42) to 0.34 (0.31-0.36), P = 0.001). CBG increased during the study (from 1126.4 nmol/L (1074.5-1178.3) to 1272.5 nmol/L (1206.3-1338.7), P < 0.001). There were no changes in the metanephrines after 12 weeks on the diet. The decrease in FCI was significant only in women, and only observed in patients using nonenzyme-inducing ASMs. We did not find any correlation between cortisol, CBG, or FCI levels and seizure frequency.

SIGNIFICANCE

After being on MAD for 12 weeks, FCI decreased significantly. The reduction in FCI may reflect reduced stress, but it may also be an effect of increased CBG. The reasons behind these alterations are unknown. Possibly, the changes may be a result of a reduction in insulin resistance and thyroid hormone levels. Treatment with MAD does not seem to influence "fight or flight" hormones.

Ketone Bodies and SIRT1, Synergic Epigenetic Regulators for Metabolic Health: A Narrative Review

Ketone bodies (KBs) and Sirtuin-1 (SIRT1) have received increasing attention over the past two decades given their pivotal function in a variety of biological contexts, including transcriptional regulation, cell cycle progression, inflammation, metabolism, neurological and cardiovascular physiology, and cancer. As a consequence, the modulation of KBs and SIRT1 is considered a promising therapeutic option for many diseases. The direct regulation of gene expression can occur in vivo through histone modifications mediated by both SIRT1 and KBs during fasting or low-carbohydrate diets, and dietary metabolites may contribute to epigenetic regulation, leading to greater genomic plasticity. In this review, we provide an updated overview of the epigenetic interactions between KBs and SIRT1, with a particular glance at their central, synergistic roles for metabolic health.

Higher levels of Bifidobacteria and tumor necrosis factor in children with drug-resistant epilepsy are associated with anti-seizure response to the ketogenic diet

Background

Recently, studies have suggested a role for the gut microbiota in epilepsy. Gut microbial changes during ketogenic diet (KD) treatment of drug-resistant epilepsy have been described. Inflammation is associated with certain types of epilepsy and specific inflammation markers decrease during KD. The gut microbiota plays an important role in the regulation of the immune system and inflammation.

Methods

28 children with drug-resistant epilepsy treated with the ketogenic diet were followed in this observational study. Fecal and serum samples were collected at baseline and three months after dietary intervention.

Findings

We identified both gut microbial and inflammatory changes during treatment. KD had a general anti-inflammatory effect. Novel bioinformatics and machine learning approaches identified signatures of specific Bifidobacteria and TNF (tumor necrosis factor) associated with responders before starting KD. During KD, taxonomic and inflammatory profiles between responders and non-responders were more similar than at baseline.

Interpretation

Our results suggest that children with drug-resistant epilepsy are more likely to benefit from KD treatment when specific Bifidobacteria and TNF are elevated. We here present a novel signature of interaction of the gut microbiota and the immune system associated with anti-epileptic response to KD treatment. This signature could be used as a prognostic biomarker to identify potential responders to KD before starting treatment. Our findings may also contribute to the development of new anti-seizure therapies by targeting specific components of the gut microbiota.

Funding

This study was supported by the Swedish Brain Foundation, Margarethahemmet Society, Stiftelsen Sunnerdahls Handikappfond, Linnea & Josef Carlssons Foundation, and The McCormick Genomic & Proteomic Center.