Milk intolerance is a big issue for British men and women.

In fact, an estimated one in five people suffer some sort of reaction to milk or dairy.

A small minority, between 0.1% and 0.5% of the adult population, have a cows' milk allergy, which often manifests in symptoms such as an itchy mouth, an itchy red skin rash and swelling of the face. In its most severe form, milk allergy can result in anaphylaxis.

Anyone who thinks that they might suffer from a milk allergy should stop consuming cows' milk immediately and consult a medical professional. More information on cows' milk allergy can be found on the websites of Allergy UK and the Anaphylaxis Campaign.

Galactosaemia is another rare, yet significant, 'milk issue' – affecting around one in 45,000 British children. Symptoms include jaundice, lethargy, poor feeding and weight loss. Anyone who believes that they or their children may have galactosaemia should halt the consumption of milk and consult their GP. For more information on galactosaemia, click here.

More common than both cows' milk allergy and galactosaemia are intolerances to aspects of cows' milk which can cause digestive problems such as bloating, abdominal pain, nausea and diarrhoea and/or constipation.

Lactose intolerance is often thought to be the cause of these irritations but in around 68 percent of cases it could be a different form of milk intolerance. There are many types, but one of the main forms is an intolerance to protein in milk. For example, issues could be caused by a reaction to the A1 beta-casein protein found within most cows' milk.

Often people omit dairy from their diet altogether but this can lead to consuming insufficient amounts of calcium, which is important for bone health. For people who cannot consume cows' milk, other sources of calcium include spinach, broccoli, dried apricots, oranges and tinned sardines.