Is soy milk better for you than cows' milk
Our expert: Denise Griffiths
http://www.abc.net.au/health/talkinghealth/factbuster/stories/2011/11/10/3358951.htm
Not so long ago there was only one type of milk: it came in a glass bottle, it had a shiny metal top and the milkman left it on your doorstep before the sun came up. This milk came from cows and most people drank it.
These days plain old cows' milk is viewed with a certain amount of suspicion and it's often believed to be the cause of health issues ranging from high cholesterol to excess mucus production. Our increasing distrust of cows' milk has conincided with a dramatic increase in the number of dairy alternatives you can buy.
One of the most popular of these is soy milk, which comes from soy beans, and is regarded by many as a far healthier choice. But is this really the case?
"Soy isn't automatically a better choice than dairy in every case," says accredited practising dietitian Denise Griffiths.
"If you're having full-fat dairy, then soy might be a better alternative, but if you're making good choices with your dairy products then there's no need to switch."
Complete food
Griffiths says there's nothing in the scientific literature to suggest we all need to replace cows' milk with soy milk. Both are good sources of protein and a range of other essential vitamins and minerals, although cows' milk is naturally a better source of calcium.
"The reason we drink [cows'] milk as humans is because it is one of the most complete foods in our diets and it contains many of the nutrients that we need," she says.
"The calcium in dairy foods is really easily absorbed by the body, especially in comparison to plant foods that contain calcium, such as broccoli, as the body isn't always able to get the calcium out of these plant foods."
We need calcium to help us maintain healthy bones and other essential processes in our body, . Once this has happened, milk cannot be digested properly, causing flatulence or diarrhoea. In humans who continue to consume lactose-rich dairy products throughout their lives, lactase enzymes are maintained in the gut. But some unlucky individuals become lactose intolerant and, for them, soy milk is a useful alternative as it contains no lactose. For everyone else, though, lactose has some advantages over other sugars because it has a very low glycaemic index. This means that it is released slowly into the blood, avoiding abrupt spikes in blood glucose levels.