Is dark chocolate good for weight loss?

Who doesn’t love to indulge in some dark chocolate every now and then? Dark chocolate is derived from the cocoa bean and often has a higher cocoa content compared to its milk chocolate counterpart. Cocoa is rich in flavanols, a type of polyphenol, which have been linked to various health benefits, such as reducing the risk for type 2 diabetes and cardiovascular diseases.^1,2 But could these cocoa polyphenols also play a role in weight loss?

Research has hypothesized that polyphenol rich dark chocolate has a beneficial effect on fat and carbohydrate metabolism, as well as on satiety, or that simply a small, sweet snack reduces food cravings and thereby can aid in weight loss.³ However, while these studies offer promising insights, it is important to consider the broader context. Dark chocolate is energy-dense (531 kcal per 100 g, on average)⁴ and can contribute, like any other food, to weight gain if eaten in excess. Weight gain (or weight loss) results from an imbalance between calories consumed and calories used by our bodies. Eating more calories than the body needs leads to fat storage and weight gain over time.⁵ Dark chocolate is also high in added sugars (42 g total sugars per 100 g, on average) and saturated fats (21 g per 100 g, on average).⁴ It is both recommended to limit added and free sugars to as low as possible and to get less than 10% of our total daily energy intake from saturated fats (about 20 g per day for a 2,000 kcal diet) to reduce the risks of non-communicable diseases.

A few studies have shown that eating chocolate is associated with a lower body mass index (BMI).^6,9 However, these studies were cross-sectional, and thus cannot show cause-and-effect. With these types of studies reverse causality is a common problem: you cannot be sure whether eating chocolate affects one’s weight or vice versa. In fact, the association diminished when researchers excluded participants with preexisting obesity-related illness. In other words, eating chocolate did not make participants lose weight, but rather participants made dietary changes (such as eating less chocolate) after becoming ill.⁹

More robust evidence comes from prospective cohort studies and human intervention studies and systematic reviews and meta-analyses summarizing these results. Randomized clinical trials lasting from 2-8 weeks where participants ate 20-50 g of dark chocolate daily did not report any significant changes in weight.⁹ However, this might be due to the study duration which was not sufficient to identify changes in weight. Another systematic review and meta-analysis of randomized clinical trials reported no significant effect of cocoa or dark chocolate on body weight, BMI, and waist circumference.¹⁰ However, when analysing a subgroup of participants eating more than 30 g of chocolate per day and a subgroup of trials lasting between 4-8 week, they did show a reduced weight and BMI. Overall, there are conflicting results, indicating that more research is needed. Particularly, the optimal amount of chocolate which is beneficial and how long chocolate should be eaten require more attention.

Takeaway

• Dark chocolate is energy-dense and contains a moderate amount of saturated fats, as well as added sugars (depending on the brand and product), which are recommended to limit. Like any other food, eating dark chocolate in excess can contribute to weight gain as weight gain results from overall caloric imbalance (e.g., regularly consuming more energy than we burn over long periods).
• Some cross-sectional studies showed that eating chocolate is significantly related to lower BMI. However, they do not show cause-and-effect.
• Evidence on the relationship between dark chocolate and weight loss from cohort studies and human intervention trials is limited and more studies are needed to draw conclusions.
• To manage your weight, choose nutrient-dense foods, make water or unsweetened beverages your drink of choice, and limit foods and drinks high in fat, sugar, and salt – check the nutrition label to help identify these.

References

1. Hooper, L., Kay, C., Abdelhamid, A., Kroon, P. A., Cohn, J. S., Rimm, E. B., & Cassidy, A. (2012). Effects of chocolate, cocoa, and flavan-3-ols on cardiovascular health: a systematic review and meta-analysis of randomized trials. The American journal o
2. Grassi, D., Desideri, G., Mai, F., Martella, L., De Feo, M., Soddu, D., ... & Ferri, C. (2015). Cocoa, glucose tolerance, and insulin signaling: cardiometabolic protection. Journal of agricultural and food chemistry, 63(45), 9919-9926.
3. Farhat, G., Drummond, S., Fyfe, L., & Al‐Dujaili, E. A. (2014). Dark chocolate: an obesity paradox or a culprit for weight gain?. Phytotherapy research, 28(6), 791-797.
4. Dutch Food Composition Database (NEVO). NEVO-online version 2021/7.1. Retrieved from https://nevo-online.rivm.nl/Home/en
5. Hall, K. D., Farooqi, I. S., Friedman, J. M., Klein, S., Loos, R. J., Mangelsdorf, D. J., ... & Tobias, D. K. (2022). The energy balance model of obesity: beyond calories in, calories out. The American Journal of Clinical Nutrition, 115(5), 1243-1254.
6. Golomb, B. A., Koperski, S., & White, H. L. (2012). Association between more frequent chocolate consumption and lower body mass index. Archives of internal medicine, 172(6), 519-521.
7. Smith, L., Grabovac, I., Jackson, S. E., Veronese, N., Shang, C., López-Sánchez, G. F., ... & Zhu, X. (2020). Chocolate consumption and indicators of adiposity in US adults. The American Journal of Medicine, 133(9), 1082-1087.
8. Cuenca-García, M., Ruiz, J. R., Ortega, F. B., Castillo, M. J., & HELENA Study Group. (2014). Association between chocolate consumption and fatness in European adolescents. Nutrition, 30(2), 236-239.
9. Farhat, G. (2014). Effect of polyphenol-rich dark chocolate on anthropometric, nutritional, biochemical and physiological markers in normal weight and overweight adults (Doctoral dissertation, Queen Margaret University, Edinburgh).
10. Kord-Varkaneh, H., Ghaedi, E., Nazary-Vanani, A., Mohammadi, H., & Shab-Bidar, S. (2019). Does cocoa/dark chocolate supplementation have favorable effect on body weight, body mass index and waist circumference? A systematic review, meta-analysis and do