Helping yourself to a chunk or two of chocolate can be a cheeky treat at times - but both your dentist and doctor would recommend you don’t do it too often.

There could be one exception to this that your sweet tooth will thank you for - and that’s making dark chocolate part of your daily diet. There are more than 150k posts about dark chocolate on TikTok and well over 3.5m on Instagram, with many discussing its possible health benefits, including help for your heart, your brain and lowering the risk of diabetes.

BBC Bitesize Other Side of the Story has got together with the BBC One series Just One Thing to take a closer look at the claims over dark chocolate and our health.

In one episode of the series, fitness expert Bilal is challenged by presenter Zoe Ball to swap out his regular sugary treats for two squares of dark chocolate each day.

There have been many studies of the links between dark chocolate and a healthier lifestyle. For example, in October 2025, the British Heart Foundation's senior dietitian, Dell Stanford, looked into claims that it was good for your heart, among other benefits. Her conclusion, based on many different medical studies and trials, was that there were "promising" findings that eating around 45g of dark chocolate each week could reduce the risk of heart disease. However, Dell also pointed out that the bars we see in sweet shops and supermarkets would have lower levels of the nutrients than the chocolate used in the different studies.

Bilal admitted to Zoe at the start of the challenge that he didn't enjoy the taste of dark chocolate, but he was willing to give it a try - and he did learn more about it on his journey.

How much dark chocolate should I eat each day?

A study in December 2024 by a public health university in Boston, USA, found that people who ate at least five servings of dark chocolate a week had a 21% lower risk of developing Type 2 diabetes.

The same study compared this to eating milk chocolate. There was no connection to lowering the risk of Type 2 diabetes, but it was connected to gaining weight, which puts people at risk of developing the condition.

The university's Professor Qi Sun said: “Even though dark and milk chocolate have similar levels of calories and saturated fat, it appears that the rich polyphenols in dark chocolate might offset the effects of saturated fat and sugar on weight gain and type 2 diabetes. It is an intriguing difference that is worth exploring more.”

Dark chocolate contains more cocao than milk and white chocolate and this is where the 'healthy' part comes in. This includes something called flavanols, a nutrient found in plants which can, among other things, help keep our blood pressure low. You may also have heard about the similar-sounding cacao. This is from the same bean as cocoa, but it is not processed and has a higher level of flavanols and other antioxidants. Some dark chocolate is labelled as being high in cocoa, others as having a greater level of cacao.

What percentage of dark chocolate is healthy?

Dark chocolate is still high in sugar, however, so finishing a whole bar of dark chocolate in one sitting isn’t the same calorie-wise as having a portion of broccoli and spinach!

When Bilal got his friends to join in the dark choc challenge on Just One Thing, they encountered something you may have spotted on its wrappers - percentages. These relate to how much of the chocolate has been made from the cocoa bean. So, if a bar of dark chocolate is listed as 70% cocoa, it means the other 30% of the bar is made of other ingredients, such as sugar.

The higher the cocoa content, the more the bar will contain other elements, such as magnesium - which helps us make the chemical serotonin that boosts our mood. It also contains caffeine and something similar called theobromine - both of which help keep us alert.

It is possible to buy dark chocolate bars that are 100% cocoa, but beware - the higher the percentage, the more bitter the taste - as Bilal and his friends found as they worked their way up through chunks starting at 55% to an intense 85%.

How important are reliable sources?

The information presented on Just One Thing comes through thorough research, using studies completed by scientists who are experts in health and nutrition. These are what is known as a trusted, or reliable source. It’s important to use sources like this when researching a subject and not rely on claims made on socials - even if someone doesn’t mean it to be, they could be fake news, also known as misinformation.

Just One Thing will look at other subjects in its latest series, as well as dark chocolate. It includes trying a digital detox, eating oily fish, or even making dancing and press-ups one new thing to add to your daily routine to see it it makes a difference.

Just One Thing begins on BBC One on Monday 23 March. Episodes will also be available to watch on BBC iPlayer.

This article was published in March 2026

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