Who Should Not Drink Wheatgrass Juice?

January 4, 2026 •

4 min read

According to the National Institutes of Health, wheatgrass juice is likely safe for most people in medicinal amounts for up to 18 months, but is not suitable for everyone. While celebrated as a superfood, certain health conditions and personal sensitivities mean some individuals should exercise caution or avoid it entirely.

Quick Summary

Not everyone can safely consume wheatgrass juice. Individuals with mold or grass allergies, gluten sensitivities, compromised immune systems, or those who are pregnant or nursing should be cautious or avoid it. High vitamin K levels can also interact with certain medications.

Key Points

Allergy Warning: Individuals with allergies to mold, grass, or wheat should avoid wheatgrass due to the risk of allergic reactions, including cross-contamination.
Immune System Risk: People with compromised immune systems, such as those with HIV or undergoing chemotherapy, should avoid fresh wheatgrass due to potential bacterial or mold contamination.
Pregnancy and Nursing: Due to insufficient research and the risk of contamination, wheatgrass is not recommended for pregnant or nursing individuals.
Blood Thinner Interaction: The high Vitamin K content in wheatgrass can interfere with blood-thinning medications like warfarin, increasing clotting risk.
Diabetes Caution: Wheatgrass can affect blood sugar levels, which may interfere with diabetes medications. Diabetic individuals should consult a doctor before use.
Gluten-Free Contamination: Those with celiac disease should only consume wheatgrass certified gluten-free due to the risk of cross-contamination.
Listen to Your Body: If you experience adverse side effects like nausea or digestive discomfort, it is best to discontinue use and consult a healthcare provider.

Who Should Avoid Wheatgrass Juice? The Primary Risk Groups

Wheatgrass is derived from the young leaves of the wheat plant, and despite being rich in nutrients like vitamins A, C, and E, it is not universally beneficial. Several groups should be particularly careful before incorporating it into their diet.

Individuals with Allergies to Mold, Grass, or Wheat

One of the most significant reasons to avoid wheatgrass is the risk of allergic reaction. As part of the grass family, it can trigger adverse responses in individuals with grass allergies. Additionally, wheatgrass is susceptible to mold growth, particularly when grown indoors in wet conditions.

Grass Allergy: Symptoms can range from hives and an itchy throat to more severe respiratory distress.
Mold Sensitivity: While not all mold on wheatgrass is harmful, some individuals are highly sensitive to mold spores, which can lead to adverse reactions.
Wheat Allergy: Although wheatgrass theoretically does not contain gluten, cross-contamination is a real risk. For those with severe wheat allergies, even trace amounts can be dangerous.

People with Celiac Disease or Gluten Sensitivity

For those with celiac disease or a non-celiac gluten sensitivity, the risk of cross-contamination is a serious concern. While gluten is found in the wheat kernel and not the grass, commercial products may not be certified gluten-free.

To mitigate risk, those with gluten sensitivities should:

Opt for certified gluten-free wheatgrass products.
Consult with a healthcare provider before consumption.
Be aware that some people with celiac disease still experience adverse effects.

Pregnant or Nursing Individuals

Due to a lack of sufficient research on the safety of wheatgrass during pregnancy and breastfeeding, most healthcare professionals advise caution. Freshly grown wheatgrass, especially, carries a risk of bacterial contamination from its growing medium, which can be harmful to a developing baby or infant. It is best to avoid it during these periods unless a doctor explicitly approves it.

Medical Conditions and Drug Interactions

Wheatgrass can interact with certain medical conditions and medications, making it unsuitable for some people.

Compromised Immune Systems and Chronic Illness

Individuals with weakened immune systems due to conditions like AIDS/HIV or those undergoing chemotherapy should be wary of fresh wheatgrass juice. The risk of microbial contamination from bacteria and mold is a significant health threat when the body's defenses are low. This group should always consult a medical professional before taking any supplement.

Diabetes and Blood Sugar Regulation

Wheatgrass has been noted to potentially lower blood sugar levels. For individuals with diabetes, this effect could interfere with medication, such as antidiabetes drugs, and lead to blood sugar levels dropping too low (hypoglycemia). Close monitoring and medical consultation are essential for this group.

Blood Thinners and Vitamin K

As a rich source of Vitamin K, wheatgrass can affect blood clotting. For those taking blood-thinning medications like warfarin, a high intake of Vitamin K can counteract the medication's effects and potentially lead to blood clots. Anyone on such medication must consult a doctor to avoid serious health risks.

Comparison of Wheatgrass Risks for Different Groups


Condition / Group	Primary Concern	Potential Severity	Precautionary Action
Allergies (Grass, Mold, Wheat)	Allergic reaction (hives, respiratory issues)	Moderate to Severe (Anaphylaxis risk)	Avoid completely or proceed with extreme caution and medical guidance.
Celiac Disease	Gluten cross-contamination	Moderate (Digestive symptoms)	Use only certified gluten-free products and consult a doctor.
Pregnancy/Nursing	Bacterial/mold contamination, insufficient safety data	High (Risk to fetus/infant)	Avoid due to lack of evidence and potential contamination.
Compromised Immunity	Microbial contamination leading to illness	High (Increased infection risk)	Avoid raw, fresh juice. Consider only high-quality, pasteurized products under medical supervision.
Diabetes	Interference with blood sugar levels	Moderate (Hypoglycemia risk)	Monitor blood sugar closely and consult a doctor, especially if on medication.
Blood Thinners (e.g., Warfarin)	Interference with medication due to Vitamin K	High (Increased clotting risk)	Consult a doctor and monitor intake closely; may need to avoid.

Conclusion: Prioritize Safety and Medical Advice

While wheatgrass is promoted for its health benefits, it is not a suitable supplement for everyone. For those with specific health conditions like allergies, compromised immunity, diabetes, or those taking blood-thinning medication, the risks can outweigh the perceived rewards. Pregnant and nursing individuals should also avoid it due to safety concerns and a lack of research. Always consult with a healthcare professional before adding any new supplement to your regimen to ensure it aligns with your specific health needs and risks.

Sources

: Healthline: Wheatgrass Benefits, Side Effects, and More: https://www.healthline.com/health/food-nutrition/wheatgrass-benefits : WebMD: Health Benefits of Wheatgrass: https://www.webmd.com/diet/health-benefits-wheatgrass : Clinikally: Wheatgrass: Unpacking Its Side Effects and Precautions: https://www.clinikally.com/blogs/news/wheatgrass-unpacking-its-side-effects-and-precautions : ICICI Lombard: Side Effects of Wheatgrass: https://www.icicilombard.com/blogs/health-insurance/mb/wheatgrass-side-effects-digestive-allergic-headaches : WebMD: Wheatgrass - Uses, Side Effects, and More: https://www.webmd.com/vitamins/ai/ingredientmono-1073/wheatgrass : Gluten Intolerance Group: Is wheatgrass a wheat product that should be avoided when eating gluten-free?: https://gluten.org/faq/is-wheat-grass-a-wheat-product-which-needs-to-be-avoided/ : RxList: Wheatgrass: Health Benefits, Side Effects, Uses, Dose: https://www.rxlist.com/supplements/wheatgrass.htm : WebMD: Wheatgrass - Uses, Side Effects, and More: https://www.webmd.com/vitamins/ai/ingredientmono-1073/wheatgrass : WebMD: Health Benefits of Wheatgrass: https://www.webmd.com/diet/health-benefits-wheatgrass : Healthline: Wheatgrass: Benefits, Side Effects, and More: https://www.healthline.com/health/food-nutrition/wheatgrass-benefits : Healthline: 7 Evidence-Based Benefits of Wheatgrass: https://www.healthline.com/nutrition/wheatgrass-benefits : City Farmer: Wheatgrass and Mold: https://www.cityfarmer.org/wheatgrass.html

Frequently Asked Questions

If you have a gluten sensitivity or celiac disease, you should be very cautious. While wheatgrass itself is theoretically gluten-free (gluten is in the kernel, not the grass), cross-contamination is a significant risk. You should only use products that are third-party certified as gluten-free.

Pregnant women are advised to avoid wheatgrass juice due to a lack of sufficient safety research and the risk of microbial contamination. Since it is consumed raw and often grown in soil, it can harbor bacteria and mold that could be harmful to a developing fetus.

Yes, wheatgrass is part of the grass family and can cause allergic reactions in sensitive individuals. Symptoms can include skin rashes (hives), respiratory issues, or an itchy throat. Those with known allergies to grass or mold should avoid it.

Yes, wheatgrass is rich in Vitamin K, which is a blood-clotting agent. If you are taking blood-thinning medications, such as warfarin, a high intake of wheatgrass could interfere with the medication's effectiveness. You must consult your doctor before consuming it.

Individuals with weakened immune systems, such as those with HIV/AIDS or undergoing chemotherapy, are most vulnerable. Since fresh wheatgrass is often raw and grown in moist environments, it can develop mold that poses a serious risk to those with compromised immunity.

New users sometimes report common side effects like nausea, headaches, or digestive discomfort. This is often attributed to a 'detoxification' process. Starting with a smaller dose and gradually increasing it can help your body adjust.

For most healthy people without the specific medical conditions or sensitivities mentioned, wheatgrass is generally considered safe when consumed in moderation. It is always wise to consult a doctor before starting any new supplement.