Guide

Yes—your cells build new proteins all day, but they can only do it when they have enough amino acids and energy from food.

Yes, your cells build new proteins every day, but they can’t do it from thin air—they need amino acids, including several you must get from food.

The body can burn amino acids for calories, but it prefers carbs and fat first because turning protein into energy creates more waste and costs more steps.

No—stored fat can’t become protein because it doesn’t contain nitrogen, the element your body must have to build amino acids.

Most adults can use whey protein, yet milk allergy, lactose trouble, kidney disease, and certain meds can make it a bad fit.

Yes, some protein drinks can trigger loose stools, most often from lactose, sugar alcohols, large servings, or added magnesium.

Yes, a protein drink can trigger stomach pain when lactose, sweeteners, large servings, or fast drinking upset your gut.

Yes, some shakes can set off a headache through caffeine, sweeteners, missed meals, dehydration, or an ingredient your body doesn’t handle well.

Yes, a shake can trigger loose stools when lactose, sweeteners, large servings, or certain powders upset your gut.

Yes, a protein shake can go bad when time, heat, or poor storage let dairy, plant ingredients, or bacteria break it down.