What macros should I eat for body recomposition after 40?

On Ep. 86, Nikkiey argues you need all three macronutrients to change your body composition. Cutting one out may work for a short time, but it isn't sustainable. Her approach is to set protein from your body weight in grams per day, then let carbs and fats move around in a healthy, balanced way. She specifically pushes back on fearing carbs so much that you drop to about 10% carbs and push fats to 60%. She is clear she's speaking broadly, and exact splits depend on your body composition, lifestyle and goals. On Ep. 402 she adds that fat matters too, as part of protecting your hormonal environment along with sleep and stress management.

Calories matter as much as the split. Nikkiey explains that to build muscle and lose fat together, you have to be strength training and eating at or near maintenance, with enough total calories to fuel training and recovery. Very low calories signal scarcity, so your body protects fat and burns muscle, leaving you lighter and smaller but not leaner. Your training also has to progress, with the weight going up over time. She notes some women need to focus on building muscle first, because definition comes from muscle underneath.

If you've been under-eating protein or calories, the stall is the plan, not you. Get protein in, eat enough, train progressively, then decide between maintenance-level recomposition and dedicated phases.