The Heart Health benefits of Dark Chocolate

Kelsey Brown, BSc


March 27, 2023

If you’re anything like me, you’ll want any excuse you can get to eat chocolate. Quite often we avoid chocolate because it can be high in sugar and we think it will make us gain weight. While it’s true that regularly eating too much chocolate will ultimately lead to you putting on weight, there is certainly nothing wrong with having a bit of chocolate now and again. Specifically, dark chocolate (with >70% cocoa content) can even have some beneficial effects on your health. 

Benefits of cocoa

Cocoa is gaining more interest in relation to its potential health benefits. Cocoa is rich in a class of compounds called polyphenols, which are also found in green tea and have been known to have a protective effect on the cardiovascular system. Cocoa has been highlighted to have several health benefits including having antioxidant and anti-inflammatory effects, protecting against heart disease and hypertension and regulating blood sugar and immune function to name a few. 

Dark chocolate, which is made from cocoa mixed with fat and sugar, is known to be an incredibly rich source of flavanols, a subclass of polyphenols. Flavanols, found in foods, are gaining interest in terms of their potential to minimise inflammation which is thought to contribute to a reduced risk of certain chronic diseases including cardiovascular disease and diabetes. 

While dark chocolate isn’t everyone's favourite chocolate, it has a higher total polyphenol and flavonoid content than milk and white chocolate so would produce greater benefits to your health. 

How do flavanols interact with nitric oxide?

Nitric oxide (NO) is a molecule involved in the regulation of blood pressure; it plays a role in vasodilation (widening of blood vessels) and can have a protective effect on cardiovascular function. 

Flavanols, which are present in dark chocolate, have regularly been found to activate endothelial nitric oxide synthase, an enzyme which increases the synthesis and bioavailability of nitric oxide. This process has a beneficial effect on endothelial function (which controls blood flow and helps to regulate blood pressure) and is a biomarker for cardiovascular risk.  

Adequate production and levels of nitric oxide are important because they allow you to dilate blood vessels and maintain healthy blood pressure. When nitric oxide production and levels are too low you are at risk of high blood pressure. Therefore, it is important to maintain healthy nitric oxide production and function for cardiovascular health. 

How to get the benefits of cocoa

So how can we use cocoa to get these cardiovascular benefits? One study found that as little as 6.3 grams a day of dark chocolate (>70% cocoa), compared to white chocolate, significantly decreased blood pressure in pre-hypertensive and hypertensive patients after 18 weeks of consumption. It doesn’t take eating a lot of chocolate to get the benefits of the flavanols.

If you don’t fancy eating dark chocolate on its own, another way to get the benefits is to have cacao nibs. These are raw forms of cocoa, which can provide you with a higher flavanol content as they haven’t been through the fermentation process that needs to happen to make chocolate. Cacao nibs can also be added to smoothies or yoghurts so may be more palatable. 


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Kelsey Brown, BSc

Kelsey holds a BSc in Sport and Exercise Science (University of Winchester) and works as a part of the science team, carrying out research for trait and action creation and blog content. She plays netball for her local team and after enjoying learning her wedding dance so much has started Latin and Ballroom dance classes with her husband.

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