There are many millions of people who must be cautious about consuming milk and milk by-products. For this group, there are four principle reasons for their caution:
- Lactose Maldigestion, also known as Lactose Intolerance, or (incorrectly) as lactose allergy. The digestive system does not produce enough of the lactase enzyme to break down the complex lactose sugar into simpler sugars. The lactose sugar ferments in the small intestine, producing gas, bloating, cramps, and diarrhea.
Note that Lactose Maldigesters usually tolerate lactose in small doses, but are overwhelmed by larger quantities. Also note that it is possible to pre-treat milk with the lactase enzyme and supplement the body's natural lactase enzyme with lactase pills.
Lactose Maldigestion easily can be diagnosed by a test known as the Breath Hydrogen Level test (BHL).
Ingredients to avoid: milk, skim milk, powdered milk, lactic acid.
- Milk Allergy. This is a true allergic reaction by the body's immune system to one or more of milk's proteins, such as casein or lactoglobulin. The resulting symptoms typically include swelling, itching, bronchospasm, hives, hypotension or shock, abdominal cramps and diarrhea.
The diagnosis is suggested by positive prick tests to milk or milk component extracts or by RAST tests (not as good as prick tests). Most clinicians would be convinced by a positive prick test for milk coupled with improvement after avoidance of dairy foods, sometimes adding a single-blind challenge (the doctor or nurse knows whether the patient is getting the real milk or the placebo, but the patient does not). The gold standard for establishing the diagnosis is a double blind placebo controlled challenge, but few clinicians are set up to do this.
Ingredients to avoid: all listed above for Lactose Maldigestion, and casein, sodium caseinate, etc.
- Casein Intolerance. This is when the immune system of the body produces IgA and IgG antibodies to casein, a milk protein. The community avoiding casein are the people afflicted with autism. Casein peptides are absorbed through the intestine and collect in the kidneys. These antibodies can be detected with ELISA serum tests. This is discussed on the Reichelt page which is referenced in URL list below.
There are some very rare diseases and some conditions that either improve with avoidance of milk and milk by-products or are made worse with milk ingestion. Some examples are:
- - Heiner's syndrome (improves with milk avoidance).
- - Some children with eczema get worse with milk ingestion.
- Villous Atrophy. This is discussed in the Medline abstracts found in the Educational Institution section below. For these people the casein milk protein causes the intestinal villi to flatten, much like it does when gluten is consumed by somebody that is intolerant to gluten.
- Keeping a food diary for a month or more is a very valuable technique for determining if milk and milk by-products are a problem for an individual.