6 Major Side Effects of Eating Too Many Broccolis

Broccoli is a green vegetable that belongs to the cabbage family and is mainly grown for its flowering head. They are available in different varieties such as Calabrese Broccoli, Sprouting Broccoli, and Purple Broccoli. Being an excellent source of essential nutrients like vitamins, minerals, antioxidants, phytonutrients, dietary fibers, etc they provide various health and beauty benefits. However, overeating broccoli is bad and may give rise to side effects.

Side Effects of Eating Too Many Broccoli

Some major side effects of eating too much broccoli are as follows.

broccoli side effects

(1) Too Many Antioxidants Are Bad For Our Health

Vitamin C, vitamin A and other antioxidants in the broccoli protect our cells from free radical damage and reduce the risk of several cancers.

Free radicals are the unstabilized ions that steal electrons from the neighboring molecules to stabilize themselves, and doing so causes oxidative damage to them.

At moderate levels, antioxidants only target the free radicals in our body, but an excessive amount, they may target the healthy cells, and increase the risk of cancers.

As per a 2011 study, vitamin E overdose may increase the risk of prostate cancer by 17 percent.

Another study conducted by the National Cancer Institute found that smokers who took beta-carotene supplements were more likely to develop lung cancer in comparison to the smokers who didn’t.

As per findings of the Office of Dietary supplements, vitamin E may also increase the risk of hemorrhagic stroke.

Eating food rich in antioxidants, and also taking an antioxidant supplements may increase the risk of overdose.

If you take an antioxidant supplement, consult your doctor to ensure there’s no food-drug intolerance.


(2) Too Much Fiber Complications

Dietary fibers in the broccoli help with digestion, and other functions such as cholesterol management, detoxification, blood sugar regulation, weight management, etc.

They improve bowel movement, relieve constipation and other gastrointestinal problems like abdominal pain, indigestion, gas, bloating, flatulence, etc.

However, don’t overeat broccolis as too much fiber may over-activate the bowel movement and leads to diarrhea, constipation, irritable bowel syndrome, intestinal gas,  intestinal bloating, malabsorption, etc.

(3) May Cause Allergy

In some people, salicylate in broccolis may cause allergic reactions such as trouble breathing, wheezing, headaches, nasal congestion, skin rashes, itching, stomach pain, etc.

People who are allergic to other cruciferous vegetables like cauliflower, turnip, cabbage, etc, are likely to be allergic to broccoli.

Avoid broccolis if you are allergic to them or other cruciferous vegetables.

If you are experiencing an allergic reaction after eating broccoli, consult a doctor immediately.


(4) Eating Broccoli And Regulating Blood Sugar

Broccoli helps in managing diabetes as it has a low glycemic index of 15, and slows down the release of sugar into the bloodstream. This prevents a sudden spike in the blood sugar level.

They also contain dietary fibers that reduce the rate at which sugar is absorbed by the bloodstream, and regulate blood sugar level.

However, eating too much broccoli should be avoided as otherwise they may drop blood sugar levels abnormally and may cause dizziness, excessive hunger, excessive sweating, fast heartbeat, shakiness, irritability, confusion, or moodiness.

If you take diabetic medication, you should eat broccoli only after consulting with your doctor to ensure there is no risk of food-drug intolerance.

(5) May Cause Hypotension

Hypertension or high blood pressure is a common health problem that affects millions around the world and is a leading cause of several cardiovascular problems.

Broccoli helps in regulating high blood pressure as the potassium in it relaxes blood vessels and improves blood circulation.

However, an excessive amount of potassium may drop blood pressure below the normal range and may cause dizziness, fainting, nausea, dehydration, poor concentration, blurred vision, pale skin, etc.

Eat broccoli in moderation to avoid this risk.

If you take blood pressure medication, consult with your doctor before adding broccoli to your diet to eliminate food-drug intolerance risk.


(6) Eating Broccoli During Pregnancy And Nursing Period

Broccoli contains several essential nutrients for maintaining a healthy pregnancy.

Antioxidants like vitamin C, vitamin A, etc in broccoli protects the fetus from free radical damage, and folic acid in it helps with the brain development of the fetus.

Folic acid also minimizes the risk of neural tube defects like spina bifida.

Broccoli regulates blood sugar and helps in managing gestational diabetes in pregnant women.

However, At excessive levels, glucosinolates and dietary fibers in the broccoli may cause flatulence, diarrhea, and other digestive problems like abdominal pain, intestinal gas, intestinal bloating, etc.

Be cautious, and consult your doctor before eating broccoli during pregnancy. Ensure that there is no complication involved and no risk of food-drug intolerance.

Nursing mothers should follow suit, and consult their doctor before adding broccoli to their diet.


This article provides general information about the topic and is not to be taken as medical advice or as an alternative to medical advice, treatment, and/or diagnosis. Always consult with your doctor before trying out any of the remedies/recipes suggested in the blog post.

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