DAIRY EXCLUSION DIETS
Dairy foods, such as milk, yogurt and cheese are well recognised as sources of essential nutrients. Excluding or limiting dairy products from the diet may compromise intakes of many vitamins and minerals, particularly calcium and iodine. The decision to exclude any food group from the diet should be taken in consultation with a medical expert, such as a registered dietitian.
There are different types of vegetarian diets but in the main, vegetarians abstain from the consumption of any meat, including red meat, poultry, fish or any other animal flesh products. Given that meat is a good source of dietary protein, in its absence, dairy becomes an important source of good quality protein for vegetarians. It gives a vegetarian diet variety and also provides important nutrients such as calcium, riboflavin, vitamin B12, iodine, potassium and phosphorus. Vitamin B12 is generally only found in foods of animal origin, which means that dairy and eggs are an important source for lacto-ovo-vegetarians (a vegetarian diet that includes dairy and eggs).
Vegan diets can be healthy, but due to the fact that they exclude all animal products such as meats, eggs and dairy, it is more challenging for a vegan diet to meet the daily requirement for all nutrients, without supplementation. Vegans often need to supplement with vitamin B12 and iron to avoid anaemia. Vitamin B12 is generally only found in foods of animal origin, which means that vegans are at high risk of vitamin B12 deficiency, without supplementation. Additionally, by consuming only plant proteins vegans may find it more challenging to obtain all of the essential amino acids, which are more readily available in animal foods. Animal proteins are considered to be ‘complete’ proteins because they generally contain all of the essential amino acids that our body needs.
Any condition that prevents the consumption of dairy should be diagnosed and managed by a registered clinician so as not to compromise nutritional intake. For those that cannot consume dairy it is usually only due to cow’s milk protein allergy. Milk allergies are most common in young children (prevalence 2-3 %) but usually disappear by the time they reach 3-5 years. The other condition in which dairy is often excluded is lactose intolerance (reduced ability to digest the natural milk sugar, lactose). However, depending on the level of intolerance, most people can consume some lactose, typically a daily amount of 12-15 g. A 200ml glass of milk contains approximately 9-10 g lactose, while the amounts in yogurt and cheese is considerably less – 5.9 g in 125 ml pot of plain whole milk yogurt and 0.03 g in 25 g of cheddar cheese.
Ideally all babies should drink the milk of their own species and this is why breastfeeding is the best choice. Most mammals discontinue drinking milk once they have been weaned onto solid foods. However, infant nutrition is a specialised area and separate from general healthy eating guidelines. Cow’s milk is recognised as a nutritious food to be included after the age of 1 year. In general, humans consume the milk of other species in the same way they consume other animal products such as meat or eggs because all provide important nutrients. As humans advanced they recognised the benefits of dairy consumption; and so the practice of dairy farming evolved.