When it comes to the question of whether dairy should be a part of a healthy diet, there is a lot of confusion out there at the moment.

Is dairy really bad for you? Does it make you put on weight? Are humans really meant to eat it?

These are just some of the health and nutrition questions we put to a dietitian to help us get to the bottom of all things dairy.

Are humans meant to drink cow’s milk?

One question many people have about dairy consumption is whether humans are actually meant to consume products containing the milk of another animal.

But Margaret Rozman from Nutrition Australia says that dairy has been consumed for thousands of years in much part because of the nutritional benefits that became known.

“As humans advanced they recognised the benefits of dairy consumption; and so the practice of dairy farming evolved,” she told Mamamia. 

She further explained that lactose intolerance is not the result of a fundamental rejection of dairy by the body, stating that babies produce the lactase enzyme which allows them to digest the lactose in their mother’s breast milk.

“People go on to retain the ability to digest lactose into adulthood—though to varying degrees,” she adds. “In populations where milk consumption has been historically low, such as Japan and China, most children will have stopped producing lactase soon after weaning, meaning they are unable to absorb the lactose in milk – this is called ‘lactose intolerance’.”

Rozman further explains that in populations where milk consumption has always been high, such as Europe, most adults continue to produce lactase  – allowing them to digest dairy products comfortably, and for an important reason.

Nutrients such as calcium, protein, B vitamins and iodine can be hard to adequately replace with other foods in the diet, making an ability to tolerate milk a genetic advantage.

What does cow’s milk offer that non-dairy alternatives don’t?

There is no shortage of dairy alternatives on the market, and it’s no longer difficult to find dairy free products that are nut or soy-based.

So what’s better for you?

According to Rozman, the natural package of nutrients that cow’s milk offers has “well-established health benefits that are hard to replicate in a factory”.

She explains that dairy-based milk, cheese and yoghurt are the richest sources of calcium in the Australian diet and this calcium is easily absorbed by the body.

It’s no secret that cow’s milk is a great source of calcium, but dairy products, including cheese and yoghurt, also provide key nutrients required for bone health, energy, growth, immune function and tissue repair.

In addition, these products also offer the bone building nutrition of phosphorus and protein, and cow’s milk in particular has been shown to reduce risk of heart-disease, stroke, high blood pressure, and type 2 diabetes.

Doesn't dairy make you put on weight?

For many years essential fats were demonised and banished from the "healthy" diets of many. We now know that doesn't need to be the case.

Rozman says that some Australians avoid dairy foods due to mistaken concerns that these foods will lead to weight gain.

"Those who avoid milk, yoghurt and cheese are no less likely to put on weight and may actually be missing out on the benefits these foods can provide as part of a weight loss program," she says.

She explains that the dietary fats in dairy are combined with other essential nutrients, such as calcium and protein in foods, to promote comprehensive health.

In other words, they work together.

Rozman adds that for those who are actively trying to lose weight through calorie-controlled diets, studies show that three serves of milk, yoghurt and cheese can help people lose more weight than those who eat less dairy foods.

"This is due to the package of nutrients in dairy foods and complex nutrient interactions that come with eating whole foods in the context of a balanced diet," she says. 

"Evidence supports the consumption of both regular and reduced fat dairy foods for good health."

Regardless of the fat content of dairy products, they are definitely healthy.

Does dairy cause gut issues and bloating?

Australians are increasingly reporting digestive problems such as bloating, abdominal pain, and diarrhoea, and many cut out dairy to remedy these symptoms.

Rozman explains that the reasons for these health issues are more likely to be rooted in stress, medication, inadequate exercise and food intolerances, and that excluding dairy products can be harmful for long-term health.

"If you’re feeling a bit of tummy discomfort, it’s best to see a health professional before you radically change your diet. You want to make sure any changes you make don’t have a negative effect on your health down the track," she says. 

People with diagnosed lactose intolerance don't need to cut out dairy completely, but timing is everything, according to Rozman.

"People have different thresholds, so it’s key to know your body. Spreading dairy intake out over a day, instead of concentrating it in one meal is often better tolerated," she advises. "Hard cheeses as well as matured cheeses such as brie, camembert and feta contain virtually no lactose, and yoghurt contains good bacteria, which helps to digest lactose."

How processed is milk that you buy in the shops? Isn't it full of additives and preservatives?

The milk purchased at the supermarket is 100 percent milk.

"Plain milk in supermarket fridges has nothing added that doesn’t come from milk. Advancements in pasteurisation techniques, refrigeration and packaging mean milk can remain safe on the shelf for longer periods of time without additives," Rozman says.

Some flavoured dairy products contain additives such as sugar, flavours and preservatives which must all be named in the ingredients list. She also adds, "All food additives have passed a rigorous government approval process to be permitted for safe use."

Does skim milk have more "sugar" and is any plain dairy milk sugary?

There is actually no added sugar in plain milk, whether regular or skim.

"A quick look at a food product label reveals that plain milk contains approximately five grams of sugar per 100 mL. This is the naturally occurring carbohydrate in milk called lactose," Rozman says.

Is milk filled with hormones that can affect the human body? Can this interrupt female hormones?

There is a common misconception that dairy products contain dangerous hormones which can in turn interrupt female hormones.

But according to fertility and prenatal dietitian Melanie McGrice, dairy products are actually beneficial for fertility in particular.

"There are no hormones added to milk or dairy products in Australia.  However, like all animal foods, milk naturally contains hormones such as progesterone and IGF1," she says.

"Current research suggests that milk and dairy foods may be beneficial for fertility, and may help to reduce rates of miscarriage. Consequently, milk is safe to consume for most women, however if you’re concerned that milk is impacting your menstrual cycle or fertility, it’s wise to have a personalised consultation with a fertility dietitian," she further explained.

Dairy Australia dietitian, Amber Beaumont, also confirmed that the naturally occurring hormones in milk are broken down by the body, and aren't therefore absorbed in their active form.

"Milk does contain small amounts of naturally-occurring hormones. When you drink milk, these hormones are digested by enzymes in the gut and as a result, are broken down and not absorbed in their active form," Beaumont told Mamamia.

She explained that while other countries have been known to use Recombinant bovine somatotropin (rBST), a hormone used to increase milk production, these are strictly prohibited in the production of milk in Australia.

Is dairy consumption ethical?

While it's important to understand the nutritional value of dairy, for some people there are ethical reasons why they choose to cut animal products out of their diet. This is a personal choice.

For those who do choose dairy but want to ensure it’s ethically produced, Dairy Australia advises that by consuming milk that is branded as Australian you can be reassured that this is backed by a commitment to best practice. This includes providing best care for all animals, reducing environmental impact, improving the wellbeing of people and looking after dairy workers.

Do you have a question about dairy? Get the answers you’re looking for, from real experts with Dairy Australia's new You Ask, We Answer section on their website, dairymatters.com.au.

This content is brought to you with thanks by our brand partner, Dairy Australia.