Weak signs that you have developed lactose intolerance – “Can develop at any age”

Because lactose intolerance “can develop at any age,” says the NHS, you may unwittingly experience signs of the condition. A general digestive problem can flare up within hours of drinking milk, butter, cheese, cream, yogurt, or ice cream. “The severity of your symptoms and the timing of their onset depends on the amount of lactose you consume,” adds the NHS.

It also depends on your lactose sensitivity, as some people can drink a whole glass of milk without any problems, while others experience symptoms after drinking a drop of milk in tea or coffee.

If you notice your stomach growling, it could be a sign of lactose intolerance.

Lactose intolerance can also lead to flatulence and bloating.

Although these signs of the disease can be easily overlooked, more tell-tale signs include:

• Diarrhea
• Cramping and pain in the abdomen
• I feel sick.

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Lacking an adequate supply of lactase, milk sugar lactose cannot be broken down into glucose and galactose.

Glucose and galactose are readily absorbed into the blood, while lactose is not.

If lactose is not broken down, milk sugar remains in the digestive system, where it is fermented by bacteria.

“This leads to the production of various gases that cause symptoms associated with lactose intolerance,” explains the NHS.

“You will be asked not to eat or drink the night before the test,” the NHS said.

During the test, you will be asked to blow up a “balloon bag”; the pattern of your breath will determine how much hydrogen is present.

“You will then be given a lactose solution to drink and your breath will be checked every 15 minutes for the next few hours to see if the hydrogen levels change,” adds the NHS.

The presence of large amounts of hydrogen, over 20 parts per million (ppm), suggests lactose intolerance, as it is one of the gases produced when lactose is fermented by bacteria in the gut.