Myths are difficult to debunk - look how long the old saw that people must drink eight glasses of water a day to avoid dehydration has been around. Here's another one: fat makes you fat.
The eight-glasses-a-day mantra is still a thing. So are fears that fat will make you, well, fat - and will play havoc with your heart, weight and make it more likely you'll develop conditions like diabetes.
Now many scientists are beginning to re-draw the boundaries of nutritional knowledge, shifting away from the old thinking that saturated fats (as found in dairy) should be avoided and that the rush to 'low-fat everything' may have been misguided. In fact, in some instances, what we replaced saturated fats with may have been worse.
In a study published in the American Journal of Nutrition, the effects of full fat and low fat dairy on obesity in older women was studied. It found that those who ate more high-fat dairy had an 8 per cent lower chance of going on to become obese over time compared to those who ate less. No association was observed with low fat dairy product intake.
A separate-analysis of over 3000 people over 15 years found those who consumed more dairy fat had a 46 per cent lower risk of developing diabetes compared to those with lower intakes.
According to Time Magazine, the body of data is beginning to reveal both that full-fat dairy has a place in a healthy diet, and also how focusing on one nutrient in the diet may backfire.
When dietary guidelines began urging people to lower the amount of fat they ate, the idea was to reduce the amount of cholesterol and unhealthy fats in the body. But by focusing just on cutting out fat, experts didn't count on the fact that people would compensate for the missing fat and start loading up on carbohydrates, which the body converts into sugar-and then body fat.
Mindy Wigzell, a health and nutrition lead for Fonterra (and a qualified nutritionist), says recent studies show the science governing attitudes towards fats has been too simplistic in the past.
"They [previous analyses] have tended to look at saturated fat alone or fat in itself," she says. "But we eat food, not fat, and when you look at emerging evidence you start to see a different picture about dairy -that the fat is among other nutrients which have a role to play in cardiovascular health and weight management."
Wigzell acknowledges the debate on dietary fats between scientists, health experts and nutritionists will go on for some time yet and that contrary opinions are easily found.
"But here's what we know - there's a lot of misinformation out there about the effects of dairy and the role it and fat can play in a healthy lifestyle. Moderate consumption of dairy products does not increase your risk of heart disease, despite their saturated fat content.
"Fat in itself isn't associated with weight gain - unless we eat too much, the same as with any food. So we advise eating nutritious foods - but not too much - and to be active regularly. It doesn't mean people should go mad with fat but they shouldn't fear it either.
"What we are now seeing is scientific opinion shifting to the fact moderate amounts of milk, cheese and yoghurt are associated with better weight management, even helping with weight loss by helping to maintain muscle mass while losing body fat."
The shift back to dairy is also being driven by consumers, hungry for natural food, she says, and labels which are simple, well-defined with recognisable ingredients.
"The only ingredient in milk is...milk. It's a natural, nutritious food which, as the science surrounding it develops more depth, is becoming better understood."
NOTE: All foods should be enjoyed in moderation as part of a healthy lifestyle, incorporating a balanced diet which meets the nutrient and energy needs of the individual, plus regular exercise. Managing a healthy weight can require following a healthy lifestyle consistently over a period of time and results can vary between individuals. For dietary and lifestyle advice tailored to your personal needs, we recommend you speak with a health professional-Fonterra