It’s the vitamin that helps your blood clot when you’re injured, and it is also essential to heart and bone health – but before the tragic news that baby William Moris-Patto had died after he did not receive his routine vitamin K injection, many may not even have heard of this vital nutrient. 

Hospital staff incorrectly recorded that seven-week-old baby William had already received his vitamin K injection, a tragic mistake that meant he missed this vital boost. An inquest heard that William died of vitamin K deficiency bleeding in his brain, which occurs in about 1.7 per cent of babies who do not receive this shot at birth. 

Unlike vitamins A, B, C and D which we are all used to hearing about, vitamin K is also vital to our health and easy to consume in adulthood. Babies on the other hand are born without enough vitamin K in their bodies, and need a booster to protect them from dangerous internal bleeding.

Here’s everything you need to know about the lesser known vitamin k.

What is vitamin K?

“Vitamin K is a nutrient that helps your blood clot, which can save a baby’s life if they have an internal bleed in their brain or gut,” says Dr Cheryl Battersby, Clinical Senior Lecturer in neonatal medicine at Imperial College London. 

Along with blood-clotting, vitamin K is involved in the production of bone proteins such as osteocalcin, which is needed to prevent your bones from weakening. 

Some studies suggest that a good vitamin K intake through your diet can reduce the risk of hip fractures and protect bone strength. Other studies have also suggested that good vitamin K levels can help lower heart disease risk by preventing your arteries from hardening, a problem that can lead to heart attacks. 

Why do babies get routine vitamin K injections?

Paediatricians have recommended that newborn babies should be given vitamin K shots for more than 60 years to prevent dangerous internal bleeds. This injection is typically delivered into a baby’s thigh. 

“Babies are born with a ‘borderline’ amount of vitamin K, and don’t ingest enough of it through breast milk, meaning that until they are able to eat other foods they need this injection to protect them,” says Dr Battersby.

“It is even more important that premature babies receive this injection, as they are often prone to nutrient deficiencies and their blood vessels are more fragile than in a full-term baby,” she adds.

Why do some babies not receive the vitamin K injection?

Misinformation spread during the pandemic has led a small minority of parents to prevent their children from having this injection, says Dr Battersby. About 1 per cent of parents now opt out of it. 

“There really is no reason why a baby shouldn’t receive this injection, but during the pandemic the anti-vax crowd pushed the idea that vitamin injections are the same as vaccines and so some parents have opted out of this,” says Dr Battersby. 

“I have had parents refuse this injection, despite us explaining why it is so important. Sometimes we’ve been able to convince them to let their child have an oral vitamin K boost, but this requires three doses and is much less effective than the injection that babies are routinely given.

“The vitamin K jab is very safe. The most commonly used brand, Konakion, contains only vitamin K, water and a very small number of preservatives that prevent the injection from expiring before it’s used – so there really is no reason for parents to worry,” Dr Battersby says. 

“If you opted out of your baby having this injection when it was offered, and you’ve changed your mind, it’s a good idea to come back within those six months as your baby still stands to benefit greatly from having this.”

Can my child still develop a vitamin K deficiency if they’ve had their injection?

On the whole, early childhood vitamin injections are very effective, Dr Battersby says. “If you do allow your baby to have the vitamin K injection then you almost certainly do not need to worry that they will develop a deficiency, as when they eat they will get more of this nutrient just as you do.

“It is worth looking out for general signs that your baby is healthy however – things such as your baby’s awakeness, willingness to feed and how often they are crying will all indicate that things are OK.”

Can adults develop a vitamin K deficiency?

Deficiency in this nutrient is rare in adults, as it is produced by normal gut bacteria and is absorbed through fats in a number of widely available foods.  This vitamin is also stored in the liver and so needn’t be eaten every day, unlike some other vitamins and minerals. 

However, extreme low-fat diets may lead to vitamin K deficiency, as this vitamin is best absorbed with fat. “In this country, this isn’t something that most people need to be concerned about however, as it’s associated with extreme malnutrition,” says Dr Battersby. 

“Vitamin K is available in meat, dairy and plants so the vast majority of healthy adults do not need to worry about being deficient in this nutrient,” she adds. 

The foods that contain the most vitamin K are leafy greens such as spinach and kale. Eating fermented foods can also boost your vitamin K levels by helping your gut microbiome to produce it.