Conditions such as malnutrition, alcoholism, certain medical conditions (e.g., Crohns disease, celiac disease), or restrictive diets (e.g., veganism without adequate supplementation for *B12*) can lead to deficiencies in one or more of these crucial vitamins
Even if the underlying problem is treated appropriately and the digestive tract returns to normal, the vomiting, diarrhea, and weight loss may continuebut now because of the vitamin B12 deficiency, not the initial disease process
There's also the question of route of administration
Collagen Peptides, taken orally, carries the mildest profile, with occasional bloating or heartburn