Are dairy products good for your health or linked to issues like heart disease, food intolerance and weight gain? Stephanie Osfield investigates.
Dairy food has had a bad rap in recent years. The resulting misconceptions have led a growing number of Australians to needlessly reduce, or cut out, foods such as milk, yoghurt and cheese. This means that around 90 per cent of Aussies are not consuming the recommended three daily serves of dairy, according to the Australian Health Survey by the Australian Bureau of Statistics.
So what’s the deal with dairy? Is full fat healthy or is it bad for the heart? And does it impact your weight?
The dairy debate
For decades, Australians have been encouraged to consume reduced-fat dairy foods. Full-fat dairy was not recommended, as it contains saturated fats that were believed to increase the risk of heart disease.
New research has challenged this idea. A review by the University of Reading in the UK, the University of Copenhagen and organisations in The Netherlands looked at 29 studies and found no evidence of a link between dairy food and cardiovascular disease.
That doesn’t mean you should start loading up your shopping trolley with cream and full-fat milk. “The Australian Dietary Guidelines, which were reviewed in 2013, still recommend that people mostly eat reduced-fat dairy products to help them maintain healthy weight,” says Lisa Renn, Accredited Practising Dietitian and spokesperson for the Dietitians Association of Australia.
“Though new research has suggested that saturated dairy fat has a neutral effect on blood cholesterol levels, the reality is that full-fat dairy foods are higher in kilojoules.”
Full-cream, low-fat and skim milk have fairly similar amounts of calcium and it’s a myth that you can’t absorb calcium by consuming low-fat milk. “Another popular myth is that low-fat milk has added sugar,” says Renn. “In fact, the reason it tastes a little sweeter is because the removal of the fats makes the taste of the natural sugars more obvious.”
However, sugar is often added to other reduced-fat dairy foods, like custard and yoghurt. “When choosing low-fat products, look for options that have 15g or less of sugar per 100g,” says Renn. “Or buy plain, reduced-fat yoghurt and add berries, or a dash of vanilla or cinnamon.”
Milk and muffin tops
“There is a mistaken belief that dairy foods are fattening, when, in fact, studies show they can help people lose weight,” says Renn. “The mouthfeel and creamy texture make them very satisfying. They are a good source of protein, which makes you feel full for longer, reducing hunger and kilojoule intake between meals.”
Foods like yoghurt and cheese also have a low Glycaemic Index (GI), which means they don’t cause a big spike in blood-glucose levels or insulin after you eat them. “I often recommend low-fat dairy foods, such as yoghurt, a small skinny latte or hot cocoa, or a small low-fat fruit smoothie, as a healthy, filling snack,” says Renn.
The high protein levels found in dairy foods are also beneficial for maintaining a healthy amount of muscle. In a study at Canada’s McMaster University, overweight women were put on a weight-loss diet, combined with daily exercise. Those who consumed higher amounts of dairy lost more fat from all over their body, particularly their abdomen, as well as gaining greater muscle strength and density.
This lowering of body fat may be the reason why consumption of dairy food is linked to a reduced risk of developing type 2 diabetes. Research from Lund University in Sweden has shown that eating yoghurt and cheese can help to reduce the risk of type 2 diabetes by as much as one-fifth.
Building strong bones
Calcium is a pivotal mineral for the building and maintenance of strong bones. “Almost 99 per cent of the body’s calcium is found in the bones,” says Greg Lyubomirsky, CEO of Osteoporosis Australia. “Calcium combines with other minerals to form hard crystals that give your bones their strength and structure. A small amount of calcium is also absorbed into the blood. It is essential for the healthy functioning of your heart, muscles, blood and nerves.”
Osteoporosis Australia recommends that adults eat three to five serves of calcium-rich food every day. “Good options include a glass of milk (250ml), tub of yoghurt (200g) and a slice of cheese (40g),” says Lyubomirsky.
Help… I can’t stomach dairy!
If you are affected by lactose intolerance, dietitian Catherine Saxelby says to make sure you choose a milk substitute which is fortified with calcium. Here are the most common options.
Soy milk has a calcium, protein and kilojoule profile that is most like cow’s milk.
Rice milk is usually made from brown rice, but tends to have a high Glycaemic Index (GI).
Oat milk is high in fibre but low in calcium, unless fortified.
Almond milk is low in protein, carbohydrates and kilojoules.
Coconut milk is very high in saturated fat, so should not be consumed in large amounts.
Milk allergy vs lactose intolerance
Milk allergy occurs when the immune system has an adverse reaction to the protein in milk, which can lead to a serious response called anaphylaxis. “This can affect breathing and can be fatal if not treated with an EpiPen and medical help,” says nutritionist Dr Rosemary Stanton. “Those with an allergy to milk protein need to avoid all dairy products — in processed foods, as well. Fortunately, most affected children grow out of milk allergy by the age of about four.”
Some people are intolerant to milk’s natural sugar, called lactose. “This intolerance occurs when the body lacks an enzyme called lactase, which is needed to digest the lactose,” Stanton explains. “The lactose then passes to the large intestine, where it can cause such symptoms as bloating, pain and diarrhoea.”
That doesn’t mean that dairy foods should be avoided altogether. “Lactose intolerance is not an allergy,” says Stanton. “Most cheeses have minimal lactose and the bacteria in yoghurt break down some of the lactose, reducing the amount that reaches the intestine. For this reason, people with lactose intolerance can usually have small amounts of dairy foods, including up to a cup of milk a day, without symptoms.”
Regardless, almost 12 per cent of Australian adults are avoiding milk and other dairy foods, even though the majority have not had a medical diagnosis of intolerance, according to a survey conducted by the CSIRO and the University of Adelaide. According to the research, around 74 per cent of those who have cut out dairy have done so to relieve adverse gastrointestinal symptoms.
“The problem is that dairy foods may not be the cause of these symptoms,” says Renn. “They could be triggered by stress worsening irritable bowel or an intolerance to something else, like the natural chemicals in food, called amines and salicylates.
“Hydrogen breath tests can check whether you are lactose intolerant, but it is also a good idea to see an accredited dietitian who can help clarify if you really do have an intolerance to dairy foods. That way, you will ensure you are not needlessly missing out on the important, health-boosting nutrients in dairy foods.”