How lean should one be?

Loss of muscle mass is associated with aging. It is also associated with the metabolic syndrome, together with excessive body fat gain. It is safe to assume that having low muscle and high fat mass, at the same time, is undesirable.The extreme opposite of that, achievable though natural means, would be to have as much muscle as possible and as low body fat as possible. People who achieve that

BMI, body fat, diabetes, diseases of civilization, evolution, Fat Loss, muscle gain, muscle loss, obesity, Okinawa