hello! First of all, thank you for your concern and support for our Amway Nutrilite products! 8-year-old children can completely use the cranberry Yishi capsule. This product mainly has the function of improving eyesight. It's good for your eyes. With children's protein powder and children's multi-nutrient tablets, it will be a more complete nutritional supplement. In terms of dosage, you can take one or two capsules three times a day, depending on the specific situation. Use with meals. I give you this reply as a national certified dietitian. Thank you for your attention!