The spark factor The secret to supercharging energy, becoming resilient, and feeling better than ever

Physician Maloof debuts with a spirited manual on how to feel more energized. To help readers reach their "physical, mental, and spiritual potential," Maloof recommends picking up revitalizing habits and exercises informed by "biohacking," or "intentionally manipulating your biology to optimize your health." She breaks down how mitochondria in cells harvest energy from the food people eat and notes that regular exercise encourages mitochondria to produce more energy in anticipation of future workouts. Diets can help boost energy, but, Maloof relates, they affect people differently because of variability in genetics and microbiome composition, so she encourages readers to test for food sensitivities and fatty acid levels, then customize their diets accordingly. Reducing stress helps minimize unnecessary energy use, the author writes, and to that end she suggests readers relax by hitting the sauna, doing breathing exercises, or singing (which stimulates the vagus nerve, moderating one's heart rate). Maloof is skilled at making the science accessible to lay readers, even if some of the suggestions will raise eyebrows (she defends fasting as "completely different from starvation in one crucial way: choice"). Still, the advice mostly delivers. (Jan.)