Myth #1: Cleanses Are Always Safe
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Some juice cleansing programs want you to follow them for multiple weeks, or even permanently. That isn't safe. By switching to a juice-only only diet, you're cutting calories and missing out on key nutrients like protein and healthy fats. Therefore, these should only be temporary plans – three to 10 days – to help your body flush out toxins and inspire you to eat better afterward. 

In general, it's a good idea to run any detox plan past your doctor. But definitely consult them if you have a condition like diabetes or are taking medications, Hyman says, to make sure a cleanse won't throw your blood sugar out of whack or interfere with your overall health.