There’s been a lot of claims about cocoa helping weight loss doing the rounds recently, and whilst there is some (albeit not a lot) of evidence to support this the reality is it’s not exactly the silver bullet that some people would have you believe.
A lot of the misunderstanding comes from people mixing up cocoa and cacao. Which, is quite an easy mistake to make.
To put it simply cocoa refers to the powder obtained after the cacao beans have been roasted, fermented, and processed at high temperatures. This process reduces the bean's natural bitterness and enhances the flavor. Cocoa powder is commonly used in baking, hot chocolate, and desserts.
On the other hand, cacao refers to the raw, unprocessed form of the cacao bean. It is made by cold-pressing unroasted cacao beans, which helps retain more of the bean's natural nutrients and antioxidants. Cacao is often used in natural and organic food products.
It should be noted that when studying cocoa, scientists have noticed that there is no substantial benefit to weight loss, waist circumference, BMI etc at all. Or in the cases where there was a difference it was not statistically significant.
Particularly high flavanol (the active compounds) and high CACAO options may however, have some minor benefit.
In simple terms, dark chocolate may have some small benefit, and certain extracts could also have some benefit, but the dosages are quite high and it’s a bit of a mixed bag in terms of the studies. The ones that did show some positive results required 30 grams or more of cacao intake per day and we usually some sort of high flavanol variant. It's all a bit up in the air when it comes to cocoa and weight loss and we wouldn't come down strongly on one side or the other. Unless you're a regular milk chocolate consumer in which case, swapping to dark chocolate could reduce cravings, calories and increase satiety.
What Makes High Flavanol Cocoa Help Weight Loss?
One of the main reasons that cocoa does anything at all is quite simply that it contains caffeine, so taken in a large enough dose this can have an effect, but that’s not going to be the case with your standard cup of hot chocolate.
There is however, some reasonably compelling evidence that dark chocolate and other cacao rich options can help suppress cravings, particularly for other sweeter options and people will generally consume a smaller portion of dark chocolate than it’s less cocoa rich counter part, meaning less calories in and weight loss.
Then there’s also some evidence that cocoa can stimulate adiponectin production.  Adiponectin is a protein that plays a role in regulating metabolism and insulin sensitivity. But, this is only going to be valid in very specific use cases, despite all of the misinformation going round online about insulin sensitivity.
The Studies on Cacao and Weight Loss
We reviewed several research articles have examined the relationship between cocoa consumption and weight management, shedding light on its potential benefits.
Several randomized clinical trials have investigated the effects of cocoa supplementation on body weight. Our meta-analysis of 12 of these studies found that cocoa supplementation did not have a significant effect on body weight overall. [3,4]
However, subgroup analysis revealed that higher doses of cacao (30 grams or more per day) for a duration of 4 to 8 weeks resulted in minor reductions in body weight. These findings suggest that cacao may be more effective for weight loss when consumed in higher doses and for a longer period of time.
BMI followed the same pattern as did waist size.
Other Cocoa Studies
To offer a contrary take, a meta analysis published in the Crit Rev Food Sci Nutr, conducted a systematic review and meta-analysis of randomized clinical trials to determine the effect of cocoa/dark chocolate supplementation on body weight, body mass index (BMI), and waist circumference.  The analysis revealed that cocoa/dark chocolate supplementation had a favorable effect on these parameters. This suggests that incorporating cocoa or dark chocolate into a weight loss diet may contribute to improved outcomes. Whilst we deemed the methodology in some of these studies to be shoddy, and that the article seemed written to prove the point it should be noted that there is a contrary opinion.
There are a lot of animal studies which show cocoa to be beneficial for weight loss, and whilst we don’t put a lot of stock in these converting over to humans. As most don’t we’ll give an example for the sake of balance. Published in the Journal of Nutritional Biochemistry, one study explored the impact of cocoa powder supplementation on mice fed a high-fat diet. The results showed that the mice who received cocoa powder in their diets gained weight at a rate 21% lower than those who didn't. Additionally, the cocoa-supplemented mice had lower spleen weights, indicating reduced inflammation.  These findings are significant as inflammation is often associated with obesity and related health issues, showing there could be something in cocoa that could make a good weight loss aid.
Mood Improvements And Weight Loss
Cocoa consumption has also been shown to improve mood in adults , there is some evidence to support that raised mood can help with weight maintainance, particularly when it comes to hormonal cravings. Whilst there is no direct clinical evidence for this currently, there is a percieved wisdom around dark chocolate and PMS as well as menopausal issues. And the hypothesis could theoretically hold up, that dark chocolate or high cacao options could result in improved weight maintainance, or support dietary cravings that are common place with people who are restricting calories. But, whilst this is "common sense" there isn't a large amount of clinical evidence. In short, dark chocolate can scratch the itch of higher calorie alternatives, helping weight loss in that regard. As well as keeping mood high and potentially preventing depressive eating.
Cocoa and Weight Loss Conclusion
Cocoa and weight loss may seem like an unlikely pair, but the research suggests there may be something here, although we don't really know what. Studies have indicated that cocoa, particularly cacao, has the potential to aid in weight loss by boosting metabolism, reducing cravings, improving mood, and increasing satiety. Although there’s a lot of evidence to the contrary and it’s all a bit uncertain right now, so don’t count on dark chocolate to help you lose weight, unless you’re substituting it for something higher calorie to help lower your overall intake.
1 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6202779/
2 - https://pubmed.ncbi.nlm.nih.gov/16027246/
3 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760201/
4 - https://pubmed.ncbi.nlm.nih.gov/29553824/
5 - https://pubmed.ncbi.nlm.nih.gov/24915376/
6 - https://pubmed.ncbi.nlm.nih.gov/33711421/
7 - https://pubmed.ncbi.nlm.nih.gov/34530112/