NHS doctor Amir Khan has urged people not to throw away the watery white liquid that forms on top of yoghurt, describing it as 'liquid gold' because it is packed with protein and other nutrients.
Yoghurt is widely considered one of the healthiest breakfast options, containing high amounts of protein, calcium, and live probiotics that support strong bones, healthy digestion, and immune function. It has also been linked to reducing the risk of heart disease, lowering high blood pressure, and cutting the risk of bowel cancer, as it contains probiotics that benefit the gut microbiome.
What is the white liquid on yoghurt?
Dr Amir Khan, an NHS doctor known for appearances on ITV's Lorraine and Good Morning Britain, explained that the liquid is called whey. It naturally separates from the yoghurt because yoghurt is a fermented food.
"I know it looks a bit odd, but it's actually meant to be there, and it's called liquid whey, and it naturally separates out from the yoghurt because yoghurt is a fermented food," Dr Amir said.
Milk contains two primary types of protein: whey and casein. When milk is cultured into yoghurt, the casein protein solidifies, creating the thick consistency of yoghurt. Meanwhile, whey protein remains in liquid form through a process known as syneresis. This liquid is entirely safe to consume and does not indicate that the yoghurt has gone off.
Health benefits of eating whey protein
The whey consists largely of water but is also rich in nutrients, including protein, calcium, potassium and B vitamins, while being particularly beneficial for gut health.
"Nothing's spoiled, nothing is split, nothing is bad, it's not fat," Dr Amir reassured viewers, adding that it is packed with protein.
Research suggests that adding whey protein to a regular diet can assist in building muscle mass, supporting hormone production and maintaining bone density. When paired with a balanced diet and regular exercise, it can aid healthy, sustainable weight loss. Whey protein also delivers a substantial amount of protein, typically 20–30 grams per serving, with minimal additional fat or carbohydrate, particularly in isolate form, while slowing digestion and helping to curb overall daily food consumption.
"So don't pour it down the sink. I know it's really tempting. You're literally tipping away nutrients your body can use," Dr Amir said. "So just instead, mix it into the yoghurt, and it is really, really good for you. It's just normal fermentation. That's what yoghurt is."
"Anyway, mix it in, don't throw it away, and your body will thank you," he urged viewers.
