Flax Seed Side Effects: Risks Involved With These Nutritious Seeds
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This article is reviewed by a team of registered dietitians and medical doctors with extensive, practical clinical and public health experience.
Flax seeds are a superfood that originated in southern European and Asian countries. They are golden brown to black colored seeds that have offered a wide range of medicinal benefits for centuries.
The superfood is highly rich in multiple nutrients like healthy fats, omega-3 fatty acids, fiber, vitamins, etc. Flax seeds are usually helpful in weight loss; hence, they are a highly preferred food by dieticians.
Moreover, it may help in recovering multiple stomach issues like constipation. These seeds help improve overall health and immensely boost an individual’s immunity.
But, with numerous benefits, flax seeds have a small range of side effects. This article will cover all the possible side effects linked to the consumption of flax seeds.

Contents
12 Side Effects Of Flax Seed
May Loosen Stool
Flax seeds are known to improve constipation issues when consumed in prescribed or limited amounts. But, excessive consumption of flax seeds may cause loose stool and other digestive problems.
These seeds are highly rich in fiber; hence, large quantities increase the fiber intake leading to frequent and increased bowel movements.
Moreover, in some cases, the condition may worsen to diarrhea. If you are struggling with digestive problems, you should avoid consuming flax seeds altogether.
Also, it would be best to consume flax seeds in limited quantities to avail of the benefits.
May Cause Intestinal Blockage
It is advised to consume flax seeds with sufficient fluid for better results. The fibrous flax seeds need plenty of water for easy digestion.
Hence, if you consume excessive flax seeds without or less liquid, then it may lead to intestinal blockage or obstruction.
Moreover, people with scleroderma may experience severe constipation and bowel obstructions due to excess consumption of flax seeds.
But, if you take flaxseed oil in a limited amount, it may be effective in treating scleroderma.
May Alter Women’s Sexual Health
Estrogen is a crucial female hormone that may have a role in ovulation and the preparation of the uterus for pregnancy.
Here, regular flax seed consumption may copy the function of estrogen and alter the menstrual cycle. In severe cases, the changes may lead to infertility in some women.
Women suffering from several health conditions like hormonal imbalance, polycystic ovary syndrome, uterine cancer, ovarian cancer, etc., should avoid consuming flax seeds.
Moreover, consuming these seeds in excess may worsen the existing health conditions in women.
May Be Allergic To Some People
Several reports suggest that a few people could be allergic to flax seed consumption. An allergic reaction due to flax seeds could be inherited or acquired.
A study on flax seeds has proven that people who regularly consume flax seeds may develop allergic reactions.
The symptoms of allergic reactions could be usual or life-threatening in some instances. Some common allergic symptoms observed in people are vomiting, nausea, abdominal pain, redness, itching, swelling, etc.
But, the reaction may extend up to breathing obstructions, low blood pressure, anaphylaxis, etc.
May Lower Blood Sugar Levels
It is essential to keep an average blood sugar level to stay healthy. But, excessive flax seed consumption may lead to low blood sugar levels in non-diabetic people.
Flax seeds contain a high amount of fiber; hence, these seeds are low-glycemic food. If a non-diabetic individual consumes excess flax seeds, it may lead to low blood sugar levels.
Moreover, people suffering from low blood sugar should avoid consuming flax seeds to control their blood sugar levels.
May Lower Blood Pressure
Flax seeds aren’t directly linked to lowering the blood pressure in an individual. Suppose a person consuming medications to reduce elevated blood pressure should avoid consuming flax seeds.
If you consume these seeds along with the medicines, you may complicate the condition. Moreover, excessive consumption may cause a significant drop in blood pressure.
May Induce Bleeding
Flax seeds causing bleeding in people is a rare phenomenon, but it may cause bleeding in some circumstances.
Some people suffering from bleeding issues or who consume medicines like blood thinners to cause bleeding should avoid taking flax seeds.
Consuming flax seeds with these existing issues may increase the intensity of unwanted bleeding and may result in excessive blood loss.
Moreover, some people may find it challenging to clot blood or heal wounds faster due to flax seeds.
May Worsen Inflammation In People
Flax seeds are considered to be great for reducing inflammation. These seeds’ omega-3 fatty acid content may protect you from plaque-bound arteries.
Moreover, these crunchy seeds may ease the chronic inflammation in the arteries. A study published by the American Journal of Clinical
Nutrition has stated that flax seeds could be great medicine to reduce inflammation in people. But, it may work in reverse order if anyone consumes flax seeds in excess amounts.
Sometimes, higher consumption may lead to complications and severe inflammation in a few people.
May Increase The Risk Of Macular Degeneration
Every individual starts to lose eye power as soon as they start aging. But, consuming flax seeds may initiate vision loss early in some individuals.
Flax seeds are highly rich in alpha-linoleic acid, a type of omega-3 fatty acid.
Anyone who consumes flax seeds excessively may accumulate a massive amount of alpha-linolenic acid in their body, which may lead to macular degeneration.
Moreover, the condition may worsen to cause vision loss in a few individuals.
May Cause Prostate Cancer
Flax seeds cause prostate cancer is still a debatable question. Several researchers believe that flax seeds may have some role in causing prostate cancer.
Flax seeds are highly rich in lignan (a polyphenol), known as phytoestrogens. It is believed that the phytoestrogens resemble the estrogen in the female body.
Hence, they may create a risk of hormonal cancers, especially prostate cancer. But, the risk of prostate cancer may increase if you consume flax seeds in excess amounts.
May Be Unsafe During Pregnancy And Lactation
Several studies and researchers state that flaxseed consumption may not be safe during pregnancy.
Flaxseed consumption may cause multiple side effects during pregnancy and lactation periods in a woman. If you consume flaxseed during pregnancy, you may experience increased blood pressure.
Moreover, it may show several allergic reactions to the mother like swelling of lips, diarrhea, nausea, etc., during the pregnancy.
Furthermore, consuming flaxseed oil at the later stage of pregnancy enhances the risk of premature birth.
May Increase The Blood Cyanide Level
You might not know flax seeds contain cyanogenic glycosides that convert into hydrogen cyanide when dissolved or crushed in water.
Hence, you may increase the cyanide level in the blood when you consume raw flax seeds. The cyanide presence may be safe to an extent, but excess consumption of flax seeds may highly increase the cyanide level in the blood.
Conclusion
Flax seeds are excellent food until you consume them in a limited or prescribed amount. If you increase the flax seed consumption, you may make yourself prone to the listed side effects.
Hence, if you experience any side effects after consuming flax seeds, you should immediately contact any doctor to get the best advice.