Yes you may, however it is best to use RAW dairy-free milks. Any store-bought nut milk is not going to be raw and should therefore be avoided during a juice cleanse. We recommend trying ours or making your own which is very easy if you have a good blender (Vitamix or similar). Here is a simple recipe that can be used for cashew, almond, or hemp milks:
1 c. nuts or hemp seeds
4 c. filtered water
1 tbsp. vanilla extract
1 tbsp raw honey or 7 dates
dash of cinnamon (or more if desired)
*Note the almond milk will have to be strained with a cheese cloth or a nutmilk bag.
This recipe makes a little more than a quart. The nut milk should be refrigerated immediately and consumed within a 3-4 days.