8 Major Side Effects Of Eating Too Many Grapes

Grapes are fruit berries that belong to the deciduous woody vines of botanical genus Vitis. They are available in many variants (around 8000) like red grapes, green grapes, black grapes, white grapes, etc. but the most common variants of grapes are red, green, black and blue.  Grapes are very delicious and provide a lot of health benefits as well as beauty benefits because of the number of nutrients like vitamins, minerals, antioxidants, etc. present in them. However, it is important to note that they are healthy as long as you eat them in moderation and there are some serious side effects of eating too many grapes. In this article will know how eating too many grapes can cause damage to our health.

Side Effects Of Eating Too Many Grapes

grapes side effects

(1) Can Cause Allergic Reactions In Some Individuals

Regular and moderate consumption of grapes is not at all bad and provide many health benefits. However, there are some individuals that are allergic to grapes and they should stay away from grapes. In some people, even touching grapes can trigger allergic reactions. Allergic reactions( in some individuals) is one of the most serious ( but extremely rare ) side effects of grapes. Some of the common symptoms of grape allergy include hives, red patches, wheezing difficulty in breathing and sneezing.

In the worse case, the allergic person may go into anaphylactic shock shortly after consuming grapes. Another important point is if someone shows symptoms of allergic reactions towards grapes then it is not at all necessary that he/she is allergic to grapes. There are high chances that he/she is allergic to pesticides sprayed on the grapes and not to the grapes itself. The best way to clear this confusion is to go for an allergen test which will determine the actual cause of allergy.

(2) May Promote Weight Gain

Regular consumption of grapes is very effective in weight management and helps in losing weight because of their low-calorie content. One cup of grapes contains only 100 calories which mean you can eat them without worrying about calories. However, this advantage of grape soon turns out to be a disadvantage. This is because grapes are small and bite-sized fruits. So, it’s easy to lose track of how many grapes we have eaten and we end up eating twice or even thrice.

Doing the same on a regular basis for a long period of time can make the extra calories accumulate and give rise to weight gain. The best way to avoid this situation is to use grapes in a limited quantity. Instead of sitting down with the whole bunch, put a limited amount of grapes in a bowl and enjoy them.

Grapes are also a good source of dietary fibers which means they make our stomach feel fuller for a long time and decreases our urge to eat again and again. This also helps in weight management but then again, it is important to make sure that we don’t eat them too much as otherwise, we will end up getting more calories which will then lead to weight gain.

(3) Can Cause Carbohydrate Overload

Eating too many grapes can lead to carbohydrate overload. carbohydrate overload is a condition in which we end up getting more carbohydrate in our diet than required by our body.  Carbohydrate is a major source of energy for our body as carbohydrates get converted to glucose which acts as a fuel for our body. Our daily intake of carbohydrates should be around 45 to 60 % of the total calories we consume. This is because our body also needs other compounds like proteins, fats, vitamins, minerals, etc.

Because of this reason, it is important to eat grapes within moderation to avoid carbohydrate overload which can otherwise give rise to health problems like weight gain, Type-2 diabetics, bloating and adrenal fatigue ( source).

(4) May Cause Indigestion

Regular consumption of grapes is good for our digestive system as it helps in keeping it healthy, provides relief from constipation, indigestion, and some other digestive problems. However, eating too many grapes can lead to indigestion. This is because of the insoluble dietary fibers present in it.

The dietary fibers present in grapes is good for our digestive system but the presence of too much dietary fibers in our system is not as it can interfere with the absorption of nutrients by our intestines and in some cases, it can even cause diarrhea.

Grapes are not at all suitable for the people with fructose intolerance and they should eat grapes to avoid experiencing abdominal pain, indigestion, etc. It can even harm their liver and kidneys. Some individuals exhibit the same symptoms but with less intensity and this condition is known as fructose malabsorption.

(5) Can Cause Bloating And Flatulence

Eating too many rapes can lead to digestive problems like gas and bloat. This is because when our body digest grapes then a lot of fructose is released. Our digestive system breaks down the fructose but it is not capable of breaking it down completely and a part of it remains undigested and is passed to the gut.

These undigested sugars act like “food” for the bacteria living in the colon and they start feeding on these undigested sugars and start releasing gas. This leads to digestive problems like bloating and flatulence.  Eating too many grapes will increase the chances and severity of these digestive problems and it is, therefore, important to consume grapes within moderation.

(6) Can Cause Vomiting And Nausea

The dietary fibers present in grapes is good for our stomach and helps in keeping our digestive system healthy but this dietary fiber can be a problem if you are not used to eating a lot of fiber on a regular basis ( and your body is not habitual of digesting it ).  Eating too many grapes ( and thus consuming too many dietary fibers) in such situation can give rise to discomfort in the stomach and in some cases it can even lead to nausea and vomiting.

This is because of the difficulty faced by our digestive system to digest dietary fibers. To avoid this situation, eat grapes in a limited quantity and if your body is not habitual of digesting dietary fibers then start slow in a small quantity and gradually increase your intake ( but still keep it in moderation ).  Sometimes, the preservatives present in grapes can also trigger these reactions( like nausea and vomiting ).

(7) Can Interact With Certain Medications

Grapes are a natural blood thinner and can slow down the blood clotting process. This is an advantage of grapes as it reduces stroke risk and keeps our cardiovascular system healthy. However, grapes are not at all suitable if you are already on anticoagulant ( blood thinning) drugs like warfarin. Warfarin is a drug that slows blood clotting and makes our blood thin and grapes do the same. So, it means consuming grapes along with warfarin might increase the risk of bruising and bleeding.  In the same way, grapes may make the pharmaceuticals like phenacetin ineffective because of their ability to increase liver metabolism.

(8) Not So Suitable For Pregnant Women

Pregnancy is an important phase in a woman’s life and it is very important for the pregnant women to make sure that she keeps an eye on everything she eats and drinks as everything she will eat or drink will have a direct impact on her health and most importantly on the health of the baby developing under her. The answer to whether it is safe to eat grapes during pregnancy is filled with controversy as some experts believe that grapes are good for pregnant women because of the number of nutrients present in them.

While some experts ( majority) believes that it is better to avoid grapes during pregnancy because of the risks associated with them and most importantly because of the high level of pesticides ( around 15) present in/on them. ( source).  It is better to note to take risks during pregnancy and consult your doctor about the same. Eat grapes only when your doctor allows you to do so and only as per the amount recommended by the doctor.

Let’s take a look at some of the major risks associated with eating grapes during pregnancy are as follows:-
(a) Consuming black grapes are not at all good for pregnant women as it is believed that skin of black grapes is not digested properly by the weakened digestive system of pregnant women, and pregnant women should avoid eating black grapes.

(b) Grapes ( especially the sour grapes) are acidic in nature and eating too many grapes is not at all suitable for pregnant women because it can cause acidity in pregnant women and might lead to nausea and vomiting.  Pregnant women are more prone to heartburn and they should be careful about consuming grapes.

(c) Eating too many grapes may increase stomach heat and may lead to conditions like diarrhea. Suffering from diarrhea during pregnancy is not at all a good thing as it makes a pregnant woman lose fluids which can even be fatal during pregnancy. (source).

(d) Grapes contain a high level of resveratrol. This is a compound that possesses antioxidant and anticarcinogenic properties, but this chemical ( resveratrol) can be potentially toxic for the hormonally imbalanced pregnant women. Eating too many grapes may lead to resveratrol poisoning which can give rise to several complications during pregnancy. However, it is important to note that this is a problem only when you eat a lot of grapes at once.


The information contained in the post is for general purpose only and shouldn’t be considered as medical advice or as an alternative to medical advice. Although I’ve tried my best to keep the information contained in this post as accurate and updated as possible, I make no guarantee of the accurateness of the same.

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