Calorie consumption is important for building and maintaining muscle mass, fat loss, and body fat regulation.
It may seem like building muscle and trying to stay lean are at odds, but that's not necessarily the case. You can certainly cut back on calorie consumption and still maintain your muscle mass, but it depends on where you're starting from.
The more "luxury calories" you consume, the more you can cut back with minimal impact on your muscle mass. However, you'll have a harder time if you're already eating a pretty lean diet without many extra calories to cut back on.
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