Is low-fat dairy really better for you than full fat?

Many of us find shopping for milk, cheese and yogurt confusing. Supermarket shelves are crowded with reduced-fat and full-fat options, and there are claims and counter claims in the media about the health benefits (or otherwise) of each. We’re officially advised to reach for reduced fat versions in the UK – as is the case in many other countries – but there are some scientists challenging this recommendation. They point to research that suggests some full-fat dairy may not be as bad for us as once thought – and in some cases it could be even healthier. How are we supposed to decide?

The low-fat argument

The advice to choose low-fat dairy dates from the 1980s and is based on the idea that full-fat versions are high in saturated fat, which raises levels of ‘bad’ cholesterol and increases the risk of heart disease. In 2019, the government’s Scientific Advisory Committee On Nutrition (SACN) reviewed the evidence and its advice didn’t change. It found that reducing our consumption of saturated fat is good for our health. It recommended we limit our intake to no more than 10% of our total energy intake. To help the population achieve this, low-fat dairy is recommended. But that’s not the whole picture.

The case for full fat

Dr Duane Mellor, a registered dietician and senior teaching fellow at Aston Medical School, explains that in recent years there’s been a shift in focus, as a large body of research in the area has failed to show that low-fat dairy versions are healthier than full fat.

“When you isolate dairy products in epidemiological studies, there seem to be no benefits to the reduced fat versions,” he says, with some research suggesting full fat is better, and consumption of dairy in general being a positive health benefit.

A large 2018 study tracked the health of 136,000 people from 21 countries over nine years. It found that people who ate two or more servings of dairy per day were 22% less likely to develop heart disease than those who consumed no dairy at all. A large Swedish study in 2021 – which tracked 4,150 people aged 60-plus for more than 16 years – also found that those with the highest intakes of dairy (including full fat) had a lower risk of heart disease than those with low intakes. And a 2022 study found that eating up to 200g dairy per day had no impact on the risk of heart disease, regardless of whether it was full or low fat. Scientists are quick to point out these studies don’t prove full-fat dairy protects us from heart disease, and yet they do show an association. What’s going on?

Better understanding

Dr Mellor says some earlier studies showing the saturated fat/heart disease link had gaps because they grouped foods together when measuring intake. More recent studies have separated out different foods and revealed that consuming dairy – particularly fermented products like yogurt and cheese – may in fact “slightly” reduce the risk of heart disease.

“It could be the case that not all saturated fats or foods containing saturated  fats have the same effects on health,” Dr Mellor says, “but the mechanisms are not completely clear.” One possibility is that saturated fats in highly processed foods are a particular problem. Combined with the high levels of salt and sugar these foods often contain, the fats may impact us differently to those in minimally processed foods like cheese.

Another theory is that we process some saturated fats – those with odd numbers of carbon atoms – differently to others. It could be that these fats don’t raise our bad cholesterol like the other types. Researchers also believe it could be the range of nutrients in dairy and the way they work together – rather than fats – that are behind the benefits.

How much dairy should I eat and which types are best?

Despite the potential benefits of saturated fats in some dairy, the evidence is clear that, overall, we should limit our intake to the recommended 20g (for women) and 30g (for men) per day, says registered dietician and spokesperson for the British Dietetic Association (BDA) Clare Thornton-Wood.

“There continues to be evidence that a high intake of saturated fat is linked to disease and poorer health outcomes,” she says. This is particularly important for those with high cholesterol, who are advised to opt for low-fat dairy. Some full-fat cheese and yogurt is fine as part of a Mediterranean-style diet that’s rich in veg, fruit, grains and healthy fats, and if you reduce saturated fat in other areas.”

She adds: “Try to mix them with lower fat options – softer cheeses are lower in fat than hard cheeses, although there is some evidence that harder cheeses release fat more slowly into the bloodstream. Maybe reduce your portion size of full fat slightly and think about other high saturated choices you might make, such as pastries, cake, biscuits and pies.

The bottom line

Emerging evidence suggests that the kind of dairy you choose may be more important than the level of saturated fat it contains. Yogurt and cheese may be beneficial for heart health but more evidence is needed to prove this. If you opt for full-fat dairy, make sure you consume other nutritious foods, and keep an eye on your total saturated fat intake.

Milk, yogurt and cheese: the low-down

The pros of full-fat

• Fermented dairy like yogurt and cheese appear to have heart- protective benefits (milk seems to have a neutral effect)
• Keeps you fuller for longer so may reduce snacking on other higher fat/ sugary foods

The cons of full-fat

• More calorific and contains slightly less protein

The pros of low-fat

• Fewer calories, so can be helpful in weight management
• Less saturated fat
• Slightly more protein and calcium

The cons of low-fat

• Zero-fat flavoured yogurts often contain high levels of sugar/ sweeteners

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