When milk is not good for you.

Feb 13, 2008
When milk is not good for you
Dairy products don't go down well with many Singaporeans. GeraldineLing tells you why
What is white and creamy and can cause diarrhoea in many Singaporeans? The answer: Milk. This condition, known as lactose intolerance, occurs because the body does not have the necessary lactase enzyme needed to digest lactose, a sugar found in milk. As a result, the undigested lactose passes through the digestive system, causing nausea, abdominal cramps, bloating, gas and diarrhoea. Most people have read about lactose intolerance and may even suspect they have the condition. But many confuse it with an allergy. Lactose intolerance is not a food allergy as it does not involve the immune system. In primary lactose intolerance, lactase levels are high at birth and in early childhood. However, the irreversible, genetically-programmed loss of lactase typically starts between two and six years of age. In some cases, the loss of lactase manifests itself only after adulthood. 'I didn't have problems with milk until I hit 35,'said Madam Lee Hai Choo, 63. 'I used to drink a lot of milk when I was younger, but now I can't. 'Sometimes just drinking a cup of coffee with milk will give me diarrhoea,' said the part-time saleswoman. Sometimes, secondary lactose intolerance occurs when an injury to the small intestine causes it to produce less lactase. It typically lasts a few weeks and is reversible. In certain cases, babies are born lactose intolerant because of a congenital defect. Dr Ivy Yap, consultant physician and gastroenterologist at Mount Elizabeth Medical Centre, estimates that about 90 per cent of Chinese Singaporeans are affected by primary lactose intolerance. Data concerning lactase deficiency rates in Malays is unknown, but those in Indians 'would not be so high' because they have 'similar genes as Caucasians' who generally have low rates of lactose intolerance, surmised Dr Yap, who conducted a study investigating lactase deficiency in Chinese Singaporeans. Typically, symptoms of lactose intolerance disappear when foods high in dietary lactose, like milk and ice cream, are removed from the diet. These foods may be re-introduced 'gradually and as tolerated' by drinking smaller amounts of milk, buying low-lactose milk and using non-dairy creamers, like soya or rice milk, advised MrsMagdalin Cheong, chief dietitian at Changi General Hospital. 'Drinking or eating milk-containing foods at meal times with other foods will slow down the digestive process and therefore reduce the chance of experiencing lactose intolerance.' However, consuming less milk and milk products may put one at risk for calcium deficiency in the long term, if there is also a low intake of other dietary sources of calcium, warned Mrs Cheong. For those who must have their milk, there are supplements out in the market that can help to manage lactose intolerance. Lactase enzymes, available in tablet or liquid form, contain the enzyme needed to digest lactose, thereby reducing the amount that the body has to break down on its own. However, these supplements have to be taken over the long term if lactase deficiency is permanent and may not be advisable, said Dr Yap. In addition to the cost of the supplements, 'we also don't know if there are any side effects,' continued Dr Yap. Another suppplement used for lactose intolerance is probiotics, the 'friendly bacteria' that helps in strengthening the gut. Probiotics, often seen as 'healthy foods', are available in capsule form and can help to reduce the symptoms of lactose intolerance. 'If it does no harm, it is acceptable. But as to whether it will help alleviate the condition really depends on the individual,' said Mrs Cheong.