Recently Vogue published an article titled “Goodbye, Oat Milk: Since Learning This I No Longer Add it to My Coffee”. It’s just one in a series of articles and social media posts decrying the milk, claiming it causes dangerous blood sugar spikes, acne and bloating, and proclaiming a return to dairy milk or other milk alternatives. Sounds scary. But how much should we be worrying about our daily oat flat white habit?

“Like many forms of milk, oat milk may cause a moderate spike in blood sugar levels due to its carbohydrate content,” accredited practising dietitian Kirsten Swan tells Broadsheet. “There is limited scientific evidence to say that moderate spikes in blood sugar alone are linked to developing diabetes or other chronic diseases. But having consistently high blood sugar levels over time can raise the risk for some people.”

Swan says people should be on the lookout for food and drink with a lower glycemic index (GI) – the term used to describe how fast a food or drink containing carbohydrates raises a person’s blood sugar levels. “Oat milk generally has a moderate GI, which means it is higher GI than other milks (such as cow’s milk and soy milk), which [also] tend to have a higher protein and fat content – carbohydrate combined with protein and fat or fibre lowers a food’s overall GI.”

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Swan says people with pre-diabetes or diabetes, or those who monitor their blood sugar levels should be mindful of how much oat milk they’re drinking and consider choosing unsweetened varieties of oat milk to lower health risks.

As for inflammation, bloating and acne? Swan says though individual sensitivities to naturally occurring components (such as FODMAPs) or additives like preservatives or emulsifiers could cause such reactions, there’s not enough high-quality evidence that oat milk broadly causes these issues in the wider population.

“Like with all food and drinks, it’s best to consume oat milk in moderation and pay attention to how your own body responds,” she says.

So, given the hit pieces, are people actually ditching oat milk in favour of other dairy or plant-based alternatives? Apparently not.

“Purchasing across our shops has largely remained unchanged over the last six months,” Angus Nicol, CEO and founder of Sydney’s Black Market Coffee tells Broadsheet. “Oat milk has gradually been taking market share from light milk, soy milk and also almond milk – though this may have plateaued.”

Nicol says 50 per cent of coffees sold across his cafes are made with cow’s milk, with almond milk at 18 per cent and oat at 17 per cent. Lenka Krmencikova of Cat & Cow Coffee in Clovelly also confirms she has not seen a change in oat milk numbers recently, and Melbourne’s Market Lane Coffee also tells us it has not seen any decline in oat milk orders.

While Swan says cow’s milk is “a superior choice for people who rely on milk for calcium and protein, as well as fat-soluble vitamins, which many fortified plant-based milks (including oat milk) may lack”, whether you should be drinking oat milk ultimately comes down to individual health needs. (It’s not considered suitable for those with coeliac disease and not nutritionally suitable for children under five, for example.) Swan also says it may be worth rotating between different milks for different uses and nutrient content.

“For the average person, having a couple of oat milk beverages per day isn’t likely to cause issues,” says Swan. “While I wouldn’t classify oat milk as a health food … [it] may offer several potential health benefits. Many oat milk options on the market have been fortified with nutrients including calcium, vitamin D, and B vitamins, making it a suitable alternative for adults who are lactose intolerant or following a vegan diet.

“Depending on the degree of processing, oat milk may also contain small amounts of beta-glucan, a type of soluble fibre naturally present in oats that can help reduce cholesterol levels and promote heart health. Oat milk is naturally low in saturated fat, is cholesterol-free and offers a creamy, slightly sweet and nutty plant-based alternative to other milks, which is a big win for people who can’t tolerate cow’s milk but want to enjoy a cup of creamy coffee.”

The information Kirsten Swan has provided is based on her own opinion and understanding of the available research and it is not intended to replace individual nutrition advice.