I should say for those of us over 40, it is definitely a myth.
Some of us were actually able to eat whatever we wanted 20+ years ago, but even then it would have been difficult to have beautifully toned muscles.
Your muscles require certain nutrients to grow and develop the toned appearance that gets rid of the flabby arms.
I go into these details in the Fit Found Me Weight Loss Challenge, but some of the tips included are:
– Increase lean protein – Increase vegetables – Decrease junk food, processed foods – Increase water – Track calories in – Exercise 5-6 days per week