It has been proven that probiotics produce a huge number of vitamins, such as: Vitamin A Vitamin K Vitamins B1-B3, B5-B7, B9, B12 Essential Fatty Acids So perhaps the need for B-vitamin supplementation is really a call for proper probiotic colonization. I look forward to the day when probiotic companies and organic food companies put vitamin companies out of business. Additionally, probiotics also increase the digestibility, bioavailability and processing of a large number of nutrients, including: copper calcium magnesium iron manganese potassium zinc proteins fats carbohydrates sugars milk phytonutrients cholesterol For example, Bio-15 Probiotic , as it undergoes a tedious 6 years natural fermentation process, contains 18 types of Amino Acids, 10 types of Vitamins, 9 types of Minerals & 4 types of Organic Acids. Imagine All that plus 15 strains of Clinically tested Friendly Bacteria & Prebiotics in just 1 capsule!