Ketone Utilization in Heart and Kidney Metabolism with D-βHB Supplementation: Clinical Findings

Objectives

To investigate how the heart and kidneys use ketones as an energy source in healthy subjects after short-term fasting (fasted), a Boost® liquid meal (fed), and with or without the consumption of a single dose of an exogenous ketone salt called D-β-hydroxybutyrate (D-βHB), included in a sachet containing NR. D-βHB is a ketone that serves as an energy source that is produced by the body when it breaks down fats instead of carbohydrates.

Journal

Frontiers in Physiology

Key Outcomes

• D-βHB increased plasma ketone levels by 10-fold, regardless of whether the subjects were in a fasted or fed state, and enhanced ketone uptake in the left ventricle, especially in the fed state.
• In the fed state, D-βHB boosted left ventricular ejection fraction—indicating improved heart pumping efficiency—compared to the fasted state. It also lowered hormone levels, including insulin, gastric inhibitory polypeptide (GIP), and C-peptide, bringing them closer to fasted-state values, suggesting that ketones may influence the heart's energy preference.
• Fasting reduced ketone metabolism by 52%, but D-βHB supplementation reversed this effect, increasing ketone metabolism by 30% in the fasted state and 37% in the fed state.

Duration

Single session; 2 doses

Dose

0.50 g*

*Each sachet was composed of 0.50 g NR, 12 g D-βHB, 15.20 g of a mixture of D-βHB salts, and 1.98 g of excipients.

Study Design

Randomized, open-label, crossover study in 10 healthy subjects