Is dark chocolate healthy? Benefits, risks and how much to eat

It can seem like the foods we crave the most are never the healthiest ones. Especially if you have a sweet tooth.

But people have long been shouting about the supposed health benefits of dark chocolate. Could it be that swapping milk chocolate for something richer with more cocoa solids will appease our cravings and support our health?

Nichola Ludlam-Raine, registered dietitian, BDA , externalspokesperson and author of How Not to Eat Ultra-Processed, explains what's true and what's not.

Dark chocolate can have some health benefits, especially ones with 70% or more cocoa. But quality varies hugely between bars and brands.

Either way, it's worth noting it's still high in calories so small portions are key – think 20–30g.

Dark chocolate contains a higher proportion of cocoa solids and cocoa butter than milk chocolate, which also has more sugar. (White chocolate contains no cocoa solids at all.)

"In the UK and EU, dark chocolate generally contains at least 35% cocoa solids, although most products marketed as dark chocolate are 50–90%," says Ludlam-Raine.

"The higher the percentage, the more cocoa-derived compounds it contains and the less room there is for added sugar."

Plain chocolate refers to dark chocolate and isn't usually made with milk. But if you're lactose-free or have allergies, check the ingredients to be on the safe side.

Dark chocolate contains cocoa flavanols – antioxidants linked to health benefits. And as 100% chocolate has the most cocoa and no added sugar "it's likely to have the highest concentration of cocoa flavanols."

But it's an acquired taste, and probably not worth forcing down if your tastebuds aren't onboard.

"A good-quality dark chocolate with 70–85% cocoa is often a more realistic and enjoyable option while still providing many of the same beneficial compounds."

"There is some evidence that cocoa flavanols can help support the health of blood vessels and may have a modest beneficial effect on blood pressure and blood flow.

"Some studies suggest regular consumption of flavanol-rich cocoa products is associated with small improvements in cardiovascular health markers.

However, many studies use high-flavanol products rather than standard bars, Ludlam-Raine, points out.

"Dark chocolate should be viewed as one small part of an overall heart-healthy diet, rather than a treatment for heart disease or high blood pressure."

"No food causes weight loss on its own, and dark chocolate is relatively energy dense," says Ludlam-Raine.

"Some people find that a small square or two of dark chocolate is satisfying and may help curb cravings for sweeter foods, which could support weight management indirectly.

"But eating dark chocolate specifically to lose weight is not supported by the evidence, and large portions could easily contribute excess calories."

Let's not overstate the benefits. Yes, it has more helpful compounds than milk chocolate – but it's not a health food.

"It's still a 'treat' food and can be high in calories and saturated fat, so I would view it as a healthier choice than milk chocolate rather than a health food in its own right," says Ludlam-Raine.

"The challenge is that flavanol content varies enormously between chocolate products and is rarely declared on packaging.

"In practical terms, a small portion of high-cocoa dark chocolate, such as 20–30g, can fit into a healthy diet, but there is no universally agreed amount that guarantees health benefits."

Yes, although the amounts are generally much lower than coffee.

A 30g portion of dark chocolate contains roughly 20–30mg of caffeine, compared with around 95mg in a cup of coffee.

"It can add up though," says Ludlam-Raine, "particularly in very dark chocolates."

So, if you're sensitive to caffeine, "very high-cocoa products are best enjoyed in moderation, particularly when it's later in the day if sleep is a concern."

Broadly speaking, the fewer the ingredients a bar has, the better. But that's not to say we can safely eat endless amounts of three-ingredient chocolate.

"While dark chocolate has beneficial compounds, it is also high in calories and often saturated fat."

So regularly eating a lot of it could still contribute to weight gain and excessive calorie intake.

"For most people, 20–30g is a sensible serving size that allows them to enjoy the taste and potential benefits without overdoing it."

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