Chocolate: The Sweet Science or a Bitter Blunder?
Good evening and welcome to my blog. This is sure to be a sweet treat, as today is World Chocolate Day! Because of this, I thought it would be fun to combine two of my favourite things: Chess and chocolate, as both have a rich history and are very addictive. It's why I love taking pieces in each, yet often end up regretting my decisions if I have too much of either in one sitting. Quite often, mistakes are made, both over the board and around my waist.
This begs the question, does eating chocolate give you an advantage in over the board chess games? Within this chockablock blog, I will delve into the science behind mixing chocolate with chess. I will also ask a few titled players some hard hitting questions like "Do you like chocolate?" to gain a clearer understanding of whether chocolate and chess belongs together, or whether they should have a break.
Contents
When Chocolate Infiltrates Chess
Nestlé's KitKat is not the first or only chocolate brand to use chess as a platform to promote their respective chocolate. For Norway Chess in 2025, several players, including Magnus Carlsen, Hikaru Nakamura and Pia Cramling were blindfolded and given Lindt chocolate to try, to see if they could accurately guess which flavours were which.
It is no coincidence that chocolate brands are choosing this avenue, as chocolate is extremely popular in the world of chess. In fact, a perennial top contender, GM Vidit Gujrathi's own sister Vedika, once launched her very own chocolate company.
I used to just prepare it for bhai (Vidit). Then in some tournaments I traveled with him, and I gave them to Anish Giri and Sagar bhai. Sagar bhai totally loved it!
Vedika Gujrathi.
Vedika also mentioned that "Chess players during their games consume a lot of chocolates for energy". Vedika's chocolates ended up selling over 1300 packs in just over a year, before Vedika decided to put a pause on this endeavour, to focus on physiotherapy. Perhaps she chose this route to help alleviate her customers stomach pain after they ate too many of her delicious chocolates!
Enjoying a small piece of dark chocolate can give you a mental boost.
The U.S. Chess Academy.
I read through every article I could find for this section, to make sure that I was as well informed as possible. This was of the upmost importance, as I don't want to share or encourage any misleading health advice. The simple truth, however, is that much of these articles and research papers contradict one another in parts, as there still isn't a true consensus on the benefits and drawbacks of consuming chocolate, especially in relation to chess.
What I did discover that helped me immensely in linking the significance chocolate has to the vast majority of chess players, was an observational survey about chess and nutrition, made back in 2007. This was by Roberto H. Baglione, who is a nutritional scientist. While the survey wasn't focused specifically on chocolate, it discovered that chocolate is by far the most preferred food for Grandmasters while playing over the board chess. In fact, 80.5% of the 72 Grandmasters surveyed shared that they eat chocolate during games (Vedika Gujrathi really was on to something). Roberto concluded that moderate quantities of food (including chocolate) should be taken when a game becomes long. These two points were greatly appreciated, and was hugely helpful in my research, because information on this obtuse topic was quite scarce. In fact, this is one of the only studies on this, and the first of its kind to refer to the nutritional practices of elite chess players.
Unfortunately, Roberto never named any players that took part in this survey. His other credulous conclusions about chess and nutrition were mostly suggestions to eat breakfast, as well as training ones body for fluid consumption. He shared wisdom such as "feeling thirsty is a sign of needing a drink", and then proceeded to talk about the characteristics of urine. At the very bottom of his research paper, he proceeded to pat himself on the back (as would I) that he once defeated an Argentine IM (GM today) at a simul session in 1984. For a few hours after I learnt this, I attempted to find out who he played, yet, no records of this game exists. Roberto really loves leaving chess players anonymous! However, if I were to hazard a guess, while it could have been Gerardo Barbero or Daniel Cámpora, Carlos García Palermo fits the timeline the best.
At this point, it was still up in the air as to whether eating chocolate before and during a chess game was the way to go. It is debatable that chocolate boosts you mentally like The U.S. Chess Academy stated, or whether it's simply restoring lost energy. If it's the latter, then being well-fed might be a better option to avoid the side effects that come from eating chocolate. Interestingly, The World Anti-Doping Authority (WADA), which sets the rules that FIDE enforces, recommends dark chocolate, and is against sugar intake. WADA never directly mentions milk chocolate. It should be noted that dark chocolate has significantly more caffeine in it than milk chocolate. Furthermore, between 1984 to 2004, FIDE banned having more than 12 micrograms per millilitre of caffeine in competition. For the Americans who don't know what 12 micrograms per millilitre is, it would be the equivalent to having 7 dark chocolate bars.
While the FIDE Handbook's Nutrition and Exercise Guide doesn't explicitly mention chocolate, it is against refined sugars, stating that "poor glycemic control and acute ingestion of high glycemic index carbohydrate foods leads to lower performance and memory impairment”. It also states that "a diet high in saturated fats and refined sugars such as sucrose and fructose can contribute to cognitive impairment and decline". This is interesting, because the U.S Chess Academy listed chocolate (albeit dark) as one of the bests foods to build your cognitive function. Finally, it FIDE states that "consuming carbohydrates is essential, especially for cognitive function and performance”, which is important, because milk chocolate is known for having fast carbs. They are here for a good time, not a long time. While the carbs in dark chocolate last longer.
On top of the above factors, there really are too many variables and when combining chocolate and chess to even acknowledge, such as what else has been consumed, the amount of chocolate you are eating, whether it is milk or dark chocolate, whether you eat small amounts regularly or a lot all at once, genetics, medical conditions and so on. However, using all of the information I have gathered as a baseline, chocolate is more effective in restoring energy, rather than boosting what your normal level is. These effects tend to wear off after an hour or two, causing a sugar crash, which often lasts for an hour on average, especially if you consumed milk chocolate.
With this in mind, I have made an example chart that highlights the difference between having chocolate before a game vs being fully-fed (note that fully-fed doesn't mean full).
This chart has a lot in it to digest, pun intended. I chose to show the effects of having chocolate before the game because it best depicts the cycle of what could transpire when chocolate is used as a means to gain an advantage. The key takeaways are that chocolate isn't a substitute for a proper meal. Also, as titled players have openings prepared, having chocolate just before the game would actually be wasted, especially if playing as white. This would inevitably cause the player to have a sugar crash at around the middle of the game, where top level players might be thinking critically for the first time. One might suggest this to mean that once you begin eating chocolate, you should keep eating it periodically until the game is over!
However, this would be ignoring the long term effects that will be caused through this level of consistent gluttony. FIDE has explicitly stated that too much sugar can cause type-2 diabetes, which they observed leads to memory impairment. This means that what might have been a short-term gain will potentially lead to a long-term loss. That said, FIDE's focus in this regard was on sugar, not chocolate. It's important to highlight that sugar isn't the only component of chocolate. Chocolate also contains caffeine (as mentioned above) and theobromine, which can help you feel more awake. A good meal, if too large, might actually do the opposite, especially if eating it not long before the game. Also, fully-fed doesn't mean going to an all you can eat restaurant, then stacking up your finished plates until they touch the ceiling.
Although I personally prefer milk chocolate, there is extensive research that mentions the dangers of having too much sugar. Because of this, I believe that eating a piece or two of dark chocolate each hour once you reach the middle game may be a solid strategy and solid alternative if you wanted to eat chocolate. Another benefit of dark chocolate is that it increases your blood flow. This would only become a negative if you eat too much at once, which causes blood to flow from your brain and affect your thinking. Furthermore, a great indicator for when to consume chocolate would be in times when you're beginning to think about food rather than about your next moves. Chocolate isn't there to give you superpowers; it's there in situations where your brilliant powers are depleting because of how much energy you have exerted over the board.
If dark chocolate isn't your jam, WADA also suggests having fish, however, this would feel like an odd midgame snack to whip out. The other positive option they suggest is coffee (I'm assuming without several scoops of sugar, as sugar, bread, pasta and energy drinks are listed in their negatives when it comes to nutrition). Roberto H. Baglione's midgame snack suggestions (other than chocolate) were fruit (which 14.6% of the 72 Grandmasters that were surveyed stated they have), cereal bars (only 9.8%), almonds and raisins. The U.S Chess Academy suggested yoghurt, turmeric and broccoli. Finally, NM Sam Copeland, who stated that a sugar crash will affect your performance in the latter stages of a game, suggested to bring fruit or energy bars with you.
While not as extensive (or anonymous) as Roberto H. Baglione's questionnaire, I asked five high-level chess players five questions involving chocolate. These chess players are:
- Ethan (@theeldest1 on chess.com), who is 16 years young. His chess.com ratings are 2500 blitz, 2700 bullet, and ~2400 rapid, and his USCF rating is in the mid-2000s.
- @Isengard1, a male junior, who is a FIDE Master, with an Elo of 2280.
- Roger (@Rodgy on chess.com), an NM, who is 17 years old, with a USFC rating of 2200, and a FIDE rating of 2140.
- @CanidateMaster, who is ironically an NM, is 12 years old, with a FIDE rating of 1918, and a chess.com rating of 2762 in blitz.
- Jovana (@jolie92 on chess.com) who is a WGM (and an RM). She is 34 years old, with a peak rating of 2342.
Do you consume chocolate before/during competitive chess matches?
Ethan: I have not made a habit of eating chocolate before OTB chess games, however, I will occasionally have a snack bar or something else to keep my energy up. I often feel hungry in the middle of a game, and hunger isn't a great thing to occupy your mind while you try to calculate, so I'll eat a snack. But chocolate usually isn't my snack of choice.
Isengard1: Normally I don't eat chocolate before or during games. I find that the sugar gives you a good energy boost, but it wears off quickly and leaves you even more exhausted than before, which is why I prefer something like bananas. However, it can be very helpful in time-pressured phases during deep endgames or critical phases.
Roger: Yes, I usually keep a bar of chocolate during tournament games and take eat a few squares here and there during the game. it keeps me alert and I've done it for so long that it's almost like a ritual/good luck charm.
CanidateMaster: I mostly consume chocolate during a chess match, because I need energy to stay focused, especially in long matches, and eating chocolate also makes me feel happy because the chocolate I eat is pretty good.
Jovana: I don't enjoy too much sugar. I prefer to drink some sports drinks, like electrolyte-enhanced water. A banana is just fine, not too sweet for me. Though when I was younger, I did eat chocolate during games on some occasions, as it was advised, but I can't say if it really improved my memory, as I think hydration does that much better.
It was fascinating how each player seemed to understand the effects of sugar, and were very grounded in their approach to what they ate, with none choosing to eat chocolate before their games. I was surprised that two out of five players eat bananas, as, while fruit was mentioned in my research, bananas weren't specifically brought up by FIDE, WADA, the U.S Chess Academy or Roberto. However, bananas are a great source of energy midgame. I enjoyed how Jovana only ate chocolate because she was advised to, and I liked how CanidateMaster mentioned that eating chocolate makes him feel happy, as comfort was a key takeaway in my chart for consuming chocolate.
Chocolate didn't seem as popular as the 80.5% that Roberto's survey found. This may simply be based on having a smaller pool of people, however, the first FIDE document I could find that mentions sugar in a negative light was in 2013, which is six years after Roberto conducted his survey. Furthermore, it has now been nearly 20 years since this survey was conducted. The worldwide stance on sugar and chocolate has drastically shifted. Gone are the days when budding World Champions were hoarding chocolate, like Botvinnik reportedly did less than 6 months before he became The Sixth World Chess Champion. Coincidence?
Grandmaster Mikhail Botvinnik demanded 7kgs of chocolate at the 'Moskva' restaurant. (The next day) he purchased an additional 10kgs of 'Golden Label' chocolate.
S.N Kruglov - USSR Minister of Internal Affairs.
Do you like chocolate? If so, what is your favourite?
Ethan: I do like chocolate! My favourite brands would be Lindt and Whittaker's (a New Zealand brand), and I prefer milk chocolate with mint or fruit fillings.
Isengard1: I do! My favorite chocolate is probably dark with nougat, but white is also very good. There's a Swiss brand called Lindt, that I recommend.
Roger: I like chocolate and my favourite is the orange infused dark chocolate from Lindt. I usually alternate between the orange flavour and the sea salt flavour, both from Lindt.
CanidateMaster: I like chocolate, my favorite brand is Feastables (really!). I prefer the milk chocolate flavor.
Jovana: I eat chocolate sometimes, but I'm not a real fan of it. I prefer it with 70% or more cocoa. I am more of a person who enjoys salty or slightly spicy food. It awakens me better than sugary food.
80% of people here statistically like chocolate, Roberto's survey is pleased. The 12-year-old liking Feastables definitely tracks. I am envious of Jovana's taste buds. Growing up, I used to think only old people liked dark chocolate. While Jovana is double the age of the second oldest person I interviewed, she's still younger than me, so in conclusion, age isn't the factor. Also, three out of five mentioning Lindt is remarkable. There is a reason Lindt has a lot of involvement with chess.
Is there a sweet spot (pun intended) for how much chocolate benefits your performance, rather than becoming too much?
Ethan: On the scale of a lot to a little, the amount of chocolate should definitely be on the small side. Too much would hamper your brain or lead to a sugar rush, but a small amount could keep your energy up without crashing your cognitive state.
Isengard1: I think something like one chocolate bar is just right, nothing more, as the drop in concentration would be too much later. This small boost is actually already good enough.
Roger: Potentially like four squares of chocolate per game is quite reasonable. I normally have food before my games, so I'll end up eating a piece after a long think during a critical position, so that's usually 3-4 times a game I'd say. Anything more than that is probably too much.
CanidateMaster: For me, 500 grams is enough. It's like a perfect spot for my performance in games. I got a lot of good results from eating this much chocolate.
Jovana: I don't think I ever ate more than two chocolate bars during a game, as I obviously didn't need more, so perhaps I cannot properly answer this question. I was not really using it during games, and when I did, I didn't notice any improvements in how I was handling the position. I believe in natural sugars that come from fruits, not so much in artificial ones. Again, the only good thing after eating chocolate is that I have to drink a lot of water afterward, so maybe it did help my hydration indirectly.
While reading these, I was like "Very reasonable, Ethan. Good amount, Isengard1. Great choice, Roger... CANIDATEMASTER HAS 500 GRAMS?! (over a pound) WE NEED TO GIVE YOU AN INTERVENTION!!... Well said, Jovana". I'm going to hope that this was a typo by CanidateMaster. Otherwise, I'd recommend getting some health insurance soon. There is still hope for you.
Would you encourage other chess players to eat chocolate during over the board games?
Ethan: I don't think I would necessarily encourage players to eat chocolate during games, it's more up to what you think you need to stay focused. A little bit could help you, but also could detract from your performance. I often drink fruit juice or something like that which helps me with energy levels, but it all depends and I don't think chocolate would give me much of an advantage over someone who doesn't eat it.
Isengard1: Sure, it could give you the edge if you take it at the right moment and consume a good amount. If you take it too early and too much, you’ll be completely exhausted for the rest of the game, which can last for hours.
Roger: It depends on if you like chocolate or not. If you do then I would say it's quite refreshing and nice to snack on every now and then. Additionally, it's a pretty quiet snack so it won't make too much noise while playing.
CanidateMaster: I won't encourage other chess players to eat chocolate, because I think that some chess players might have allergic reactions. However, I believe that eating chocolate actually gives me a lot of advantages, such as feeling more focused than my opponent. Also, when you play past dinner time, eating chocolate might help me feel full.
Jovana: Keeping energy optimal is definitely needed during the game, but in my experience, sports drinks (here I mean water mixed with some vitamins and electrolytes), plus one banana, are just enough for a few hours of play. I've sometimes seen people bring 2 × 1.5 litres of water to drink during the game, and it makes sense to me, as it also keeps me more alert. Coffee, for example, makes me anxious and more stressed. Chocolate actually acts similarly for me, or even makes me sleepy. I think one to two chocolate bars are probably fine if that is your thing, but relying only on that during a match is not enough.
These were all very grounded and considerate answers. I especially appreciated how Roger thoughtfully mentioned that chocolate was a plus because it is a quiet snack. Perhaps he encourages all of his opponents to eat chocolate for this very reason. Furthermore, no one wants to have an editorial piece written about their poor eating etiquette...
A child loudly crunched on potato chips while playing. Even after the TD instructed him to not eat in the playing room, he continued noisily while staring directly at his opponent.
From Lee Bennett's editorial piece "That's Rude", in the Virginia Chess Newsletter, in relation to one of many incidences he noticed during the 2023 Virginia State Championships.
Are there any mandates on bringing chocolate into playing halls?
Ethan: I don't believe there are any specific mandates, just the normal ones about being respectful to your opponent, being quiet, not rummaging through your bag in the middle of a game, etc. If I bring a snack to a game, chocolate or otherwise, I would take it in, keep it below my table, then take it outside of the hall to eat it.
Isengard1: Not really, generally, eating at the board isn't looked upon favorably, even though it isn't forbidden—but you can simply step aside a few steps and eat your snacks there.
Roger: from my experience no, but I do believe that some tournaments are more strict when it comes to food.
CanidateMaster: No, there is not any mandates on bringing chocolate into playing halls, however, some tournaments may scan your chocolate bar to see if you're hiding anything in there. There are a few tournaments in my area that doesn't allow any food inside, so yeah, it depends on which tournament and the rules.
Jovana: You can bring chocolate, water, or something really small that can, for example, fit in a purse, but you can't really bring a sandwich to eat, as it's not allowed. At many international tournaments, like continental events or the Olympiad, we already have water and coffee available in the playing hall, and often some fruit like apples and bananas, and even sweets like chocolate bars, so you don't need to bring anything with you. This is also what they consider fitting within their regulations.
This question was more for my curiosity, as I am yet to go to an over the board tournament. It's nice to know that the regulations are strict, but fair, and seem to universally apply regardless of the level. If I do go, I will bring dark chocolate, and leave my potato chips at home.
Are there any added thoughts you would like to share?
Ethan: I don't think chocolate is harmful to your play during a game, but you should take care with how much you consume. And it's not magic, you still have to win the game! Probably any snack would do the trick in terms of keeping your energy up, and most players pick chocolate because it tastes good.
Isengard1: As mentioned before, I prefer something where the energy boost lasts longer, like bananas, but consuming chocolate does make sense under suitable circumstances. However, I think it’s important, if you want to play a focused game you should view chocolate as a pure energy boost rather than just a tasty snack.
CanidateMaster: Maybe I'll get a toothache if I didn't brush my teeth. Also, sometimes I have shared my chocolate with other players, which was actually legal in some small tournaments I have participated in.
Great thoughts, Ethan. In the end, it's not the chocolate that's making the moves. Isengard1, viewing chocolate as an energy boost rather than just a tasty snack is a great way to look at it. Also, CanidateMaster, if you are bringing 500 grams of chocolate, I think sharing it is best, if not, brushing won't be enough to save you from getting a toothache 
Firstly, major thanks goes to the five wonderful players that took their time to answer all of my questions. it was much appreciated and very insightful. I wrote this blog wanting to know whether chocolate gives players an advantage in over the board chess games. With the science, as well as the answers to my questionnaire in mind, I have concluded that chocolate truly can give a player an overall advantage. The juxtaposition here is in the variables. It can give the player an advantage, if this player:
- Eats breakfast and is well-fed before the game and remains hydrated throughout the match.
- Chooses dark chocolate, as it has more caffeine, less sugar, and has slower carbs than milk or white chocolate.
- Begins eating the chocolate only once critical thinking is being applied and an energy boost is needed (not pre-game).
- Is eating small amounts at a time, with gaps in between.
- Doesn't eat 500 grams.
Chocolate really does help, however, chocolate alone won't single-handedly win you the game. It is at its best when part of a litany of other sensible choices. If chocolate is used in the moments when a player begins to feel peckish during a tricky middle/endgame, it becomes great fuel to prevent the player from feeling depleted. However, while chocolate can help players mentally during games, it shouldn't be seen as a premeasure to boost ones cognition. Furthermore, bananas, cereal bars, almonds, raisins and even broccoli can also do the same trick. Lastly, if the opponent suddenly pulls out chocolate as well (which, according to my questionnaire would most likely be Lindt) the advantage you thought you had is now abruptly gone!
I'm not suggesting that players shouldn't eat milk or white chocolate during games. Comfort is a big component that makes chocolate a great choice, especially if you are a sweet tooth. I would simply encourage these players to keep an eye on their sugar intake. With all of this said, I can definitively say with all confidence, that chocolate and chess truly belong together.
Thank you so much for reading my blog. Even though bitter dark chocolate is the better way to go in over the board chess games, it was very sweet of you to stick around until the end. Also, you're probably not in a tournament and It's still World Chocolate Day, so go and enjoy whatever chocolate you like! I hope you all have a beautiful night.
