strong enough to pulverize the veggies and fruits to digest them better. (think baby food- easy to digest) Smoothies give you the juice plus all the fiber.
Another possibility is a juicer, any juicer that does a great job of extracting juices will do. I have a Jack Lalanne juicer it does a great job but will not juice greens (for greens you need a special juicer - or just put the greens in the blender and put them in a nut milk bag ---available at Whole Foods and other health food stores---and squeeze to extract the juice.)
If you rate the foods that you eat all day and pick the ones that are the most nutrient dense this will help you close the gaps on any deficiencies you may have. If you have been tested and shown to have defiencies eat the foods with nutrients you are lacking. You can find this information easily on the internet. This is a great site (I put in kale- check out the nutrients!) http://nutritiondata.self.com/facts/vegetables-and-vegetable-products/2461/2
You don't have to be perfect and pick the most nutrient dense one each time...just make sure you pick the best food most of the time, the more healthy the food/drink choices the healthier you will be!