It is hard to make a general recommendation, you have to find what works best for you in regards to frequency of Blast intake. It depends on what else you eat throughout the day and what you can tolerate. Blasting is a great way to address the symptoms associated with gastritis. It is important to monitor and understand which foods cause irritation as everyone can be different with what they can tolerate. Including anti-inflammatory foods can help soothe the body. Check out this article for some great tips: http://www.nutriliving.com/blog/top-10-anti-inflammatory-foods. These foods are great to add to a Blast: cabbage, celery, aloe vera crystals, chia seeds, even small potatoes help. Those are the ones that you want to use more. Juicing is a great source of nutrients without the added fiber. Try foods like apples, pears, spinach, kale, wheat grass, grapes, apricots, melon, any type of berries, turmeric, ginger, etc. Avoid chocolate, coffee, anything spicy and nuts. Additionally it may be important to provide low fiber foods during a flare up where he may be experiencing diarrhea. Include foods like bananas, oats, peanut butter and coconut water.