vniow said:
The key word here is babies. There's a reason why many people grow up to be lactose intolerant, their bodies grew out of having to need the stuff in order to sustain themselves.
Lactose intolerance is the inability to digest significant amounts of lactose, the major sugar found in milk. Lactose intolerance is caused by a shortage of the enzyme lactase, which is produced by the cells that line the small intestine. Lactase breaks down milk sugar into two simpler forms of sugar called glucose and galactose, which are then absorbed into the bloodstream. Not all people deficient in lactase have the symptoms commonly associated with lactose intolerance, but those who do are said to have lactose intolerance.
People sometimes confuse lactose intolerance with cow’s milk intolerance because the symptoms are often the same. However, lactose intolerance and cow’s milk intolerance are not related.
Being intolerant to cow’s milk is an allergic reaction triggered by the immune system. Lactose intolerance is a problem caused by the digestive system.
Some causes of lactose intolerance are well known. Primary lactase deficiency is a condition that develops over time. After about age 2 the body begins to produce less lactase, though most people will not notice symptoms until they are much older.
Secondary lactase deficiency occurs when injury to the small intestine or certain digestive diseases reduce the amount of lactase a person produces. These diseases include celiac disease, inflammatory bowel disease, and Crohn’s disease.
Researchers have identified a genetic link for lactose intolerance. Some people are born with a likelihood of developing primary lactase deficiency because it has been passed to them genetically (inherited from their parents). This discovery may be useful in developing a diagnostic test to identify people with the condition.
Harvard University researchers recently examined the relationship between dairy consumption, obesity, and factors leading to the development of type 2 diabetes in young adults. For this analysis, more than 3,000 young adults from 4 US cities completed a questionnaire that documented lifestyle habits, including smoking status, physical activity, and diet. A physical exam and blood tests measured blood pressure, cholesterol levels, blood sugar levels, and body fat.
Study participants were monitored over a 10-year period, and were diagnosed with insulin resistance syndrome if they had at least two of the following symptoms: high blood sugar, obesity, high blood pressure, and a combination of low HDL cholesterol and high triglycerides. Among the volunteers who were somewhat overweight, there was a significantly lower incidence of IRS characteristics --- obesity, high blood pressure, abnormal blood sugar levels --- in those who ate more dairy foods. Those who ate at least 5 servings per day (of milk, cheese, yogurt, and dairy-based desserts) reduced their odds of developing IRS by
72%, even after taking into consideration other dietary and lifestyle factors that affect the likelihood of developing IRS.