If you're over 40 and training, you need 1.2–1.6g of protein per kg of body weight per day - and how you spread it across meals matters as much as the total. The official RDA of 0.8g/kg is outdated and likely inadequate for maintaining muscle.
Most celebrity physiques - especially superhero transformations - are either genetically exceptional, chemically enhanced, or both. Science gives us actual numbers to calculate your natural ceiling based on your frame. The sooner you know yours, the sooner you stop chasing someone else's genetics.
Of the hundreds of supplements marketed to build muscle, boost testosterone, and improve performance, only a handful have solid evidence behind them. Creatine works. Protein works (if you're not getting enough from food). Everything else ranges from 'maybe helpful in specific situations' to 'complete waste of money.' This guide tells you which is which.