Nutrition myth buster: Are dairy foods really responsible for inflammation?

Jennifer Bowden

Nutrition writer·New Zealand Listener·

18 Jul, 2026 07:06 PM4 mins to read

‌

Subscribe to listenAccess to Herald Premium articles require a Premium subscription. Subscribe now to listen.Subscribe now

‌

SaveShare this article

Reminder, this is a Premium article and requires a subscription to read.

Copy LinkEmailFacebookTwitter/XLinkedInReddit

Some say dairy causes inflammation, contributes to skin conditions such as acne, and leads to gut issues or bloating. Are they right? Photo / Getty Images

As well as Jennifer Bowden’s columns in the NZ Listener, listener.co.nz subscribers can access her fortnightly myth busters column which explore food and nutrition myths.

Among the many foods deemed “suspicious” by online commentators, dairy occupies a particular place. It is said to “cause
inflammation”, contribute to skin conditions such as acne, and lead to gut issues or bloating. The message is simple and increasingly familiar: what was once a dietary staple is now framed as something our bodies struggle to tolerate.

But behind these claims lies a more complicated question: does dairy cause inflammation and should we avoid it?

Depression, stress and diet all modify inflammation levels in our body. However, in a healthy body, inflammation is a helpful and normal response to specific triggers such as fighting infections, healing tissue injuries and clearing damaged cells.

The key distinction is whether inflammation is acute versus chronic. Acute inflammation is short term and often protective and necessary, whereas chronic inflammation is long term and associated with diseases such as diabetes and cardiovascular disease. Yet online discussions often collapse all inflammation into one, framing it in black and white terms as “harmful” when it is often a sign the body is doing exactly what it should.

Scientific evidence on dairy and inflammation is less contradictory than it first appears. Large reviews consistently find little to no effect of dairy consumption on inflammatory markers in the general population. Yet some newer studies suggest replacing dairy milk with alternatives such as soy milk can lead to modest reductions in inflammation. The distinction is subtle but important: these studies are not showing that dairy actively promotes inflammation, but that, in certain dietary contexts, other foods may produce more favourable anti-inflammatory results. This is less about the inherent negatives of dairy and more about the potential positives of adding plant-based foods.

When it comes to acne, a complex interplay of hormones, genetics and skin biology all contribute, not just inflammation alone. Scientific evidence suggests dairy milk may have a small impact on acne, but less so cheese and yoghurt, suggesting components in milk may play a specific role. However, rather than avoid dairy products altogether, a 2026 review recommended adult acne patients limit excessive intake of skim and low-fat milk as studies have found a stronger link between acne and drinking more than two glasses of low-fat milk per day. Adolescents and young adults with acne should also think twice before using whey protein supplements.

Still, dairy milk and products such as cheese and yoghurt are valuable sources of dietary calcium, which helps to build strong bones and teeth. They also offer a valuable source of protein, some carbohydrates, fats, essential vitamins such as vitamin A, B2, B12 and minerals like zinc. So there are good nutritional reasons to include dairy, or to ensure suitable alternatives with comparable nutrients.

However, for some people dairy milk can cause symptoms such as bloating and discomfort, which may be interpreted as “inflammation”. In fact, an estimated two-thirds of adults are simply unable to digest the lactose in dairy milk, with marked differences between population groups. Only around 5% of adults of Northern European descent are lactose intolerant, compared with 90% of adults of East Asian descent.

Lactose intolerant individuals typically have a reduced production of the lactase enzyme in their small intestine, which leads to bloating, diarrhoea, nausea and abdominal pain when they eat dairy.

In reality then, dairy does not appear to increase systemic inflammation in the general population. For most people, its effects are neutral, and in some cases modestly beneficial. That does not mean everyone will feel the same: lactose intolerance can cause digestive symptoms, and some individuals may notice changes in skin or comfort when they alter their intake. But these differences are not evidence of a universal inflammatory effect. Rather, they highlight a broader issue in the way nutrition is understood online — where complex findings are often reduced to simple rules, and normal bodily responses can be mistaken for signs of harm.

SaveShare this article

Reminder, this is a Premium article and requires a subscription to read.

Copy LinkEmailFacebookTwitter/XLinkedInReddit