Scientists Warn 'Boy Kibble' Meal Trend Could Lead To Serious Health Problems

A meal trend spreading across gym TikTok has raised concern among scientists, who say it could put some young men at risk of serious food poisoning.

'Boy kibble' is a simple batch-cooked meal made with ground mince and rice. It has become popular with fitness-focused young men who want a cheap, easy protein source they can prepare in large amounts and eat across the week. Videos of people making huge portions have gained thousands of views online.

But microbiologists are now warning that storing large amounts of the rice-based meal for several days can create the right conditions for dangerous bacteria to grow.

Why can boy kibble be dangerous?

The concern centers on a bacteria called Bacillus cereus, which can grow on starchy foods such as cooked rice. Cooking rice can kill living bacteria, but it does not always destroy the spores, because those spores can survive heat.

If cooked rice is then left to cool slowly at room temperature, the spores can begin to develop into bacteria. From there, they can multiply quickly, especially when a large batch of food stays warm for too long before being chilled.

The real problem is what happens after the bacteria spreads. Bacillus cereus can release toxins that cause severe food poisoning, and reheating the meal will not remove those toxins, even if the heat kills the bacteria itself.

Bacillus cereus thrives on starchy foods like cooked rice Getty stock image

Why rice can be risky in meal prep

Rice is a common meal-prep food because it is cheap, filling, and easy to cook in large portions. That is also why it appears in trends like boy kibble, where the whole point is to make enough food to last several days.

The issue is not that rice is unsafe on its own. The risk comes from how long it sits around after cooking, how quickly it cools, and how soon it goes into the fridge. Large pots of rice can hold heat for longer, which gives bacteria more time to grow.

That is why food safety advice often focuses on cooling rice fast, storing it in smaller containers, and not keeping it for too long. For people who meal prep, those small steps can make a big difference.

Dr Primrose Freestone, a food safety expert from the University of Leicester, told the Daily Mail: "It is not so much preparing batch meal cooking that is the food safety issue, but how the food is prepared and then stored."

Professor Cath Rees from the University of Nottingham also warned that symptoms can come on quickly after eating contaminated food.

She said: "It causes severe nausea and vomiting, rapid onset, usually 30 minutes to five hours after eating, and generally lasts for 12 to 14 hours."

How dangerous is Bacillus cereus?

According to the National Library of Medicine, Bacillus cereus causes around 63,400 foodborne illnesses in the US each year. It also accounts for roughly 1-2% of confirmed foodborne disease outbreaks.

Most cases are mild and clear up without medical treatment. Even so, deaths can happen in vulnerable people, which is why experts are warning against treating the risk as harmless.

The safest approach is to focus on storage. Instead of leaving one large batch to cool slowly in a pot, experts advise splitting the food into smaller containers so it cools faster, then putting it in the fridge as soon as possible.

Cooked rice should not be stored for more than one to two days Getty stock image

Cooked rice should not be kept in the fridge for longer than one to two days.

For anyone who wants to prepare meals further ahead of time, Professor Rees recommends cooking fresh rice each time and only batch cooking the mince. The mince can be stored in the fridge for three to four days when handled safely.

Another option is freezing meals instead of keeping them in the fridge for several days. Meals stored at -18°C can be kept safely for two to three months.