Aoife Hearne: What is the best source of calcium for a lactose-intolerant child? 

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My five-year-old daughter gets tummy cramps whenever she eats dairy. What’s the best source of calcium for children who may be lactose intolerant?

Before excluding any food from her diet, you need to talk to your GP to establish if there is an underlying cause of your daughter’s stomach cramps.

Lactose is a natural two-sugar molecule found in dairy products. Milk and yoghurt are rich sources of lactose, while cheese is a low-lactose food. When we eat lactose our body uses an enzyme called lactase to break apart this two-sugar molecule and make it easier to digest. For some, the body does not produce enough of this all-important enzyme, which leads to pain, discomfort and bloating when they eat lactose-rich food.

There are many lactose-free products on the market. Lactose-free milk and lactose-free yoghurt have lactase added, breaking apart the lactose molecule, making it easier to digest and reducing discomfort. These products are made with cow’s milk, so the taste is the same.

I speak from experience here since I am lactose intolerant.

Another crucial reason lactose-free products are preferable is because they contain the same amount of calcium and protein as regular cow’s milk and yoghurt. Many of the other dairy alternatives on supermarket shelves are not only lacking in calcium but tend to be low in protein too. Since these nut and plant-based drinks also taste very different to cow’s milk, it may be challenging to encourage a five-year-old to consume them.

Calcium is essential for bone health and muscle function and is vital in blood clotting. 

According to Children Health Ireland, children aged between one and 10 years need 800mg of calcium each day. A 200ml glass of milk, a pot of yoghurt and 28g of cheese all provide about 200mg of calcium each, this works out at around four servings of calcium each day.

By the age of 17, bones will have stocked up on over 90% of the calcium they will ever contain, so childhood and teenage years are critical to ensure adequate calcium is consumed. Inadequate calcium intake, leading to deficiency from childhood to early adulthood, may lead to weakened bones and, more seriously, osteoporosis in later years.

From a calcium point of view, your daughter will get more value when eating lactose-free milk, yoghurt and regular cheese (naturally low lactose). However, thinking outside of the ‘dairy’ box, foods such as broccoli, baked beans, almonds, and sesame seeds are all sources of calcium. Remember, these foods have less calcium per portion compared with dairy foods, so you need to eat more to reach the recommended intake. For example, one glass of milk contains the same calcium as 10 servings of baked beans. Aiming to have calcium-rich food at each meal and complementing this with some non-dairy choices is a good rule to achieve daily targets.

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