This is an individual matter as some people can eat dairy with no ill effects whilst others find that dairy products cause unpleasant symptoms such as respiratory mucous and infections, constipation or asthma. So it can be trial and error.
If you are lactose intolerant you will find that dairy products cause diarrhoea and bloating, unless you purchase the lactose free varieties.
If you do have an autoimmune disease, it’s best to keep your dairy intake controlled so that you do not eat large amounts at one time and so you do not eat dairy products every day.
Many people with gallbladder problems and gallstones find that they do much better without dairy products.
The most healthy dairy food choices are unprocessed cheeses (white cheeses are easier to digest), plain yoghurt (especially Greek style yoghurt) and A2 milk.
If you do drink cow’s milk, be very selective as to which type you choose as not all types of cow’s milk are healthy. It is becoming increasingly difficult for food and public health professionals to ignore the topic of A2 versus A1 milk.
A1 milk has now been implicated in the genesis of Type I diabetes, heart disease and allergies.
A2 Milk is pure natural dairy milk and is free of permeate and additives.
Conversely, today most dairy milk contains 2 main types of beta-casein protein, namely A2 and A1. Originally all dairy cows produced milk containing only the A2 type of beta-casein protein. A2 milk comes from cows specially selected to produce A2 beta-casein protein rather than A1. A2 milk is rich in A2 beta-casein protein and some people find that it assists their digestion.