Why Are You Not Supposed to Eat Seeds?

While many seeds like chia and flax are praised for their health benefits, the reason why are you not supposed to eat seeds from some common fruits is a matter of food safety. The seeds of certain fruits contain compounds that can release harmful toxins like cyanide when chewed or crushed, posing a significant risk if consumed in large quantities.

Quick Summary

This article explores the truth behind the risks of consuming seeds, detailing toxic compounds like amygdalin in stone fruits and apples, the effects of antinutrients, and the potential for allergic reactions. Certain seeds should be avoided, while others can be safely prepared to enhance their nutritional value.

Key Points

• Toxic Compounds: Certain fruit seeds contain cyanogenic glycosides like amygdalin, which release toxic cyanide when crushed or chewed.

• Antinutrients Block Minerals: Phytic acid in many seeds binds to minerals like iron and zinc, hindering their absorption, but soaking can help.

• Some Seeds are Safe and Healthy: Nutrient-rich seeds like chia, flax, and pumpkin are packed with fiber, healthy fats, and minerals when prepared correctly.

• Myth About Appendicitis: The widespread belief that seeds cause appendicitis is a myth, with modern medical evidence disproving the claim.

• Proper Preparation is Vital: Soaking, sprouting, or roasting seeds can reduce antinutrients and increase their nutritional benefits.

• Be Cautious with Pits: The hard pits of stone fruits like cherries and peaches should be discarded as they contain amygdalin, and are a choking hazard.

Seed Safety: Distinguishing Between Edible and Toxic

Not all seeds are created equal. While nutritional powerhouses like chia, flax, and pumpkin seeds are celebrated, the seeds of many common fruits contain naturally occurring compounds that can be harmful. The key difference lies in the specific plant family and the preparation method required to neutralize any potential toxins. The fear surrounding all seeds often stems from misinformation and a general lack of awareness about which ones are truly dangerous and under what conditions.

The Cyanide Concern in Fruit Seeds

One of the most well-known reasons why you are not supposed to eat seeds from certain fruits is the presence of cyanogenic glycosides. When these compounds are chewed or crushed, they can release hydrogen cyanide, a highly poisonous substance.

• Apple Seeds (and other Rosaceae family members): The seeds of apples, cherries, peaches, and apricots contain amygdalin, a cyanogenic glycoside. If the seeds are swallowed whole, the hard protective coating often prevents the release of amygdalin, allowing them to pass harmlessly through the digestive system. However, crushing or chewing them allows the compound to be converted to cyanide in the stomach. The amount of amygdalin varies by fruit and quantity, but it is best practice to avoid consuming the crushed seeds or pits of these fruits.
• Bitter Almonds: Unlike the sweet almonds commonly sold, bitter almonds contain significant levels of amygdalin and are therefore toxic if eaten raw. Roasting is one process that can neutralize these compounds.
• Lychee Seeds: These seeds contain a toxin called hypoglycin-A, which can cause severe hypoglycemia (dangerously low blood sugar), particularly if the fruit is unripe.

Antinutrients: The Hidden Seed Protectors

Besides acute toxins, many seeds and grains contain 'antinutrients.' These compounds are a plant's natural defense mechanism, but they can interfere with our body's ability to absorb vital nutrients. Proper preparation, such as soaking, sprouting, or cooking, can significantly reduce the levels of these compounds.

• Phytic Acid (Phytates): Found in the outer layer of seeds, nuts, and grains, phytic acid binds to essential minerals like zinc, iron, calcium, and magnesium, making them less available for absorption. Soaking seeds overnight is an effective method to help break down phytic acid.
• Lectins: These carbohydrate-binding proteins can cause digestive distress and, in some cases, intestinal inflammation in sensitive individuals. They are commonly found in legumes and grains but can also be present in seeds. Cooking and soaking are effective ways to reduce lectin activity.
• Tannins: These compounds can inhibit iron absorption and reduce the digestibility of proteins. Soaking and cooking can help reduce tannins.

Comparison Table: Safe vs. Cautionary Seeds

Feature	Generally Safe Seeds (e.g., Chia, Flax, Sunflower)	Cautionary Seeds (e.g., Apple, Cherry, Lychee)
Cyanogenic Glycosides	Minimal to none present.	Present, especially in seeds from the Rosaceae family. Releases cyanide when crushed or chewed.
Preparation for Safety	Can be eaten raw, but soaking or grinding can enhance nutrient absorption.	Pits and seeds should be discarded. Never chew or blend into smoothies.
Key Antinutrients	Primarily phytates. Can be reduced by soaking.	Varies, but toxicity is the main concern when crushed. Phytates can also be present.
Health Benefits	Rich in fiber, protein, healthy fats, and minerals like omega-3s, magnesium, and zinc.	The fruit flesh is nutritious, but the seed offers no health benefits and carries significant risk.
Digestibility	Easily digestible, especially when ground or soaked.	Hard pits are indigestible and pose a choking hazard or, if crushed, are toxic.

Digestive Issues and Other Concerns

Beyond toxins, certain seeds can cause digestive problems or other specific health issues.

• Diverticulitis Myth: The old medical advice to avoid seeds and nuts if you have diverticulosis has been largely debunked. Studies now show no scientific evidence that they cause diverticulitis flares. In fact, a high-fiber diet, which can include seeds, may reduce risk.
• Allergenic Potential: Seeds can cause allergic reactions in some individuals, with symptoms ranging from mild rashes to severe anaphylaxis. Allergies to seeds like sesame and sunflower are a growing concern.
• Choking Hazard: Large, intact pits, like those from cherries, are hard and can pose a choking risk, especially for young children.

The Takeaway on Seed Consumption

Understanding which seeds are safe and how to prepare them is key. While some seeds harbor toxic compounds that make them unsafe to eat, many others offer immense health benefits and should be a part of a balanced diet. The rule of thumb is to avoid the seeds or pits of stone fruits and apples, especially when crushed or blended. For beneficial seeds, proper preparation can unlock their full nutritional potential.

Conclusion

The perception that you are not supposed to eat seeds is a complex issue, rooted in genuine food safety concerns about certain fruits but also fueled by myths. The presence of toxins like amygdalin in stone fruit pits and antinutrients in grains and legumes necessitates caution and proper food preparation. By understanding these distinctions, consumers can make informed choices, safely enjoying the nutrient-rich seeds that contribute positively to health while avoiding the few that pose a risk.

Visit the European Food Safety Authority's website for more information on food safety.

Proper Seed Preparation for Maximum Benefits

• Soaking: Reduces antinutrients like phytic acid and makes minerals more bioavailable.
• Sprouting: A process that can enhance digestibility and nutritional value by deactivating enzyme inhibitors.
• Roasting: For seeds like sunflower, roasting can improve flavor and texture and neutralize some compounds, but a moderate temperature is best.
• Grinding: Grinding seeds like flax and chia makes their nutrients more accessible to the body, as whole seeds can sometimes pass through undigested.

Final Thoughts on Seed Consumption

Ultimately, the healthfulness of seeds is dependent on the type and how it is prepared. There is no universal rule that all seeds are bad, but a healthy skepticism and a little knowledge can protect you from potential risks and help you get the most out of safe, nutrient-dense seeds.

Why We Are Not Supposed to Eat Seeds: Key Considerations

• Toxins in Stone Fruits: Seeds from cherries, apples, peaches, and apricots contain amygdalin, which turns into poisonous cyanide when chewed or crushed.
• Antinutrients: Compounds like phytic acid and lectins in many seeds and grains can inhibit the absorption of essential minerals.
• Digestibility and Choking: Hard, indigestible pits from some fruits pose a choking hazard and can cause gastrointestinal discomfort.
• Allergenic Potential: Some individuals can have severe allergic reactions to specific seeds, such as sesame and sunflower seeds.
• Misinformation vs. Fact: The long-held myth that seeds cause appendicitis has been disproven by modern medical research.
• Processing is Key: Safe seeds can be prepared through soaking, sprouting, or cooking to reduce antinutrients and improve digestion.
• Balanced Perspective: While caution is warranted with specific fruit seeds, many types of seeds are incredibly nutritious and should be included in a healthy diet.

Frequently Asked Questions

Is it dangerous to eat an apple core with the seeds inside?

Accidentally swallowing a few intact apple seeds is not dangerous, as the tough outer coating prevents the release of amygdalin. However, chewing or crushing a large number of seeds is risky, as it can release cyanide. It is safest to avoid consuming the seeds entirely.

Do fruit seeds cause appendicitis?

No, this is a long-standing myth. Medical studies have shown that seeds are an extremely rare cause of appendicitis. The condition is most often caused by a blockage from hardened stool or infection.

Why are some seeds considered superfoods while others are toxic?

The safety of a seed depends on the specific plant species. Some, like chia and flax, are naturally packed with beneficial nutrients. Others, like those from stone fruits, contain toxic compounds as a protective mechanism. Proper preparation is also a factor.

Can proper cooking or preparation make toxic seeds safe?

Processing can reduce or eliminate some toxins and antinutrients. However, it is never recommended to try and neutralize the highly toxic seeds of stone fruits. For safe seeds, methods like soaking and cooking can be beneficial.

What is the role of antinutrients like phytic acid?

Phytic acid is a storage form of phosphorus found in many plant-based foods. It is considered an antinutrient because it can bind to and prevent the absorption of minerals like iron, zinc, and calcium during digestion. Soaking can help mitigate this effect.

Should people with diverticulosis avoid seeds?

The outdated recommendation for people with diverticulosis to avoid seeds and nuts is no longer supported by scientific evidence. Studies suggest that a high-fiber diet, which can include seeds, may actually reduce the risk of diverticular disease.

How can I maximize the nutritional benefits of safe seeds?

To get the most out of nutritious seeds like flax and chia, consider grinding them to make their nutrients more accessible. Soaking can also reduce antinutrients, while roasting enhances flavor and digestibility.