How many times as a kid would you hear grown-ups say "drink your milk, because it's good for you?" Pure, wholesome milk. Milk with its bone-building calcium and health-building vitamins, fortifies the body. But does it fortify the body enough?
Our reporter Brooke Hanson is on a mission to find out whether the different types of milk, with all those additives, are better for your health than just plain milk.
But why's this stuff such an important part of our diet? To find out, we caught up with Maree Garside, who's a dietitian with Dairy Australia.
"I think the reason that it is so important for us is because it provides such wonderful nutrients. It's got things like calcium, which we need for healthy teeth and bones. People often think it's just calcium but it's a lot more than just calcium it's got at least 10 really important nutrients in it," she says.
If it's got all those nutrients, what's with all the different types of milk you can buy in the supermarket? Full-cream, skim, low-fat, milk with omega-3, extra calcium, milk with vitamin D, soy, lactose free talk about variety!
But are they worth buying?
Well, we can't test them all, so we've selected just four to find out how good they are for us.
Number one is regular, full-cream milk.
Number two has added calcium for stronger bones.
Number three has vitamin D as well, to help your body absorb calcium.
And for something different we've included milk with omega-3 fatty acids they're great for your heart and brain. But we usually get them from fish.
Before revealing the results, let's find out why calcium makes healthier bones. Sonja Kukuljan studies bone disease the most common being osteoporosis.
"The technical difficulty for osteoporosis is that it's a skeletal disorder, which is characterised by compromised bone strength, and that leads to an increased risk for fractures," she says.
Engineering consultant Neil Walls is 53 and is a prime candidate for bone fractures. And guess why?
"During most of my adult life, since the time I left home, I've very rarely drunk milk as milk," he says.
That was until two years ago, when Neil joined Sonja's osteoporosis research program. As Sonja sees it, building healthy bones requires two things: our bones are made, first of all, from protein, in the form of collagen. Around that is mineral, mostly calcium and phosphorous. Together, they make the bone slightly flexible, and very strong.
Sonja got Neil drinking milk and exercising regularly. She's now going to measure how much his bone density has improved in the last two years.
Meanwhile, let's find out if milk additives make for healthier milk.
Brooke has brought Sonja along with her to help interpret the results.
How does it rate in the health stakes?
Sonja: "It provides a little bit of fat, which means you get extra energy. That can be good for kids, pregnant women etc."
For most people to get their daily calcium needs, you'll need up to four glasses of full-cream milk a day.
So Sonja, thumbs up for full-cream?
"Yes, depending on who you are."
Our next two samples, calcium-enriched and calcium plus vitamin D both returned very similar results.
The key difference is that vitamin D helps our body absorb calcium, so it's better for our bones.
Sonja: "That's good because instead of needing four glasses a day to get your requirements, you actually only need about three glasses.
So the milk with added calcium and vitamin D looks like our frontrunner.
Milk with omega-3
Can it effectively replace fish in our diet?
Sonja: "Now I was really surprised by this because one glass of it provides about half of what a woman would need and about a third of what a man will need per day. So that actually provides quite a bit of omega-3. Compare that to having two to three serves of fish per week, so that actually provides quite a bit of omega-3. Good news, but don't replace your fish altogether, you should still eat your fish."
So omega-3 additives get the thumbs up, because they're good for your heart.
But where healthy bones are concerned, our winner is the milk with added calcium and vitamin D.
However, you've got to say, all milk is great for building bones.
So a glass of milk a day is good for you. But has it been good for Neil Walls?
A non-milk-drinker for 30 years, Neil's bones were at risk of fracturing. But two years of drinking milk have paid off.
"The good news is we see small improvement in the bone density at his hip and a maintenance in the bone density at his spine and that's really good news for someone in Neil's age group," says Sonja.
Neil's improvement is a real turn up for the books as our bones usually become less dense as we age.
Sonja: "So it would seem that the combination of the exercise and the milk together is having a positive result on the bone density of Neil's hip and spine."
Now what about someone like Brooke? She's 28, fit and healthy and she's been drinking milk all her life.
How does she rate?
"Your test score, Brooke, is actually zero, and that means you are perfect. In terms of what we can say about your bone density, it's terrific. It's perfect," says Sonja. "It would appear that you're doing everything right. So keep drinking the milk, keep doing the exercise … so dairy and exercise are the key to healthy bones and choosing terrific parents, but I think you've already done that!"
So how much milk do we need?
- Children up to 11 should have between one and three serves a day.
- For teenagers, add an extra serve a day.
- Men up to 70 and women up to 50 need three serves.
- And if you're in the older age bracket, an extra serve a day is only going to do you good.
"When you're looking at choosing milk, it comes back to the one that you enjoy. You've got to enjoy food and I think the most important thing is to go for the one that you like. Generally speaking, all milks are very good and really suitable for most people I think it comes down to taste," says Maree Garside.
Don't like milk? You can get the same benefit from cheese or yogurt as well as some dairy alternatives such as soy-based products.
- Lots of people can't handle cow's milk at all! But what causes lactose intolerance? Is it something you're born with? Or can you get it later in life? It's when the body doesn't make enough of an enzyme that breaks down a type of carbohydrate or sugar in milk, called "lactose". The result is that lactose gets through to the large intestine where it can give you the runs. Some people are born lactose intolerant but, yes, you can develop it later in life. See your doctor if you're concerned.