Irritable Bowel Syndrome is a disorder of the intestines commonly marked by abdominal pain, bloating, and changes in a person's bowel habits. This may include diarrhea or constipation, or both, with one occurring after the other.

The immune system is a complex network of organs, cells, and proteins that defends the body against infection, whilst protecting the the body's own cells. The immune system keeps a record of every germ (microbe) it has ever defeated so it can recognise and destroy the microbe quickly if it enters the body again.

Inflammation is a normal part of the body's response to injury or infection. Inflammation occurs when the body releases chemicals that trigger an immune response to fight off infection or heal damaged tissue. Once the injury or infection is healed, the inflammatory process ends.

To infuse is to steep something in a liquid to extract the flavors from it. 

Ingredient transparency means being open and honest about the food supply chain and all the ingredients used in your products, whether they qualify as clean or not.

Inoculation is the immunization against disease by introducing infective material, microorganisms, or vaccine into the body.

An institutional animal care and use committee is required by federal regulations for most institutions that use animals in research, teaching, and testing. They have a key oversight role, including the review and approval of animal use activities, and inspection of animal facilities.

Iodine forms part of thyroid hormone which is essential for sustaining life in vertebrate animals.

Iron is crucial for every kind of living organism, including pants, bacteria, animals and humans, to transport oxygen (through the haemoglobin in animals and humans) and to produce energy through electron transfer in the mitochondrial respiratory chain.

The ISO is a worldwide federation of national standard bodies that is the standard for which most labs must hold accreditation in order to be deemed technically competent. In many cases, suppliers and regulatory authorities will to accept test or calibration results from a lab that is not accredited.