Beneficial Herbs for Blood Type O Positive Individuals

October 18, 2025 •

4 min read

According to the blood type diet theory, certain foods and herbs are more compatible with specific blood types based on ancestral heritage. This guide explores which beneficial herbs for blood type O positive individuals are believed to offer supportive properties for digestive health, immunity, and metabolic function.

Quick Summary

The blood type diet suggests specific herbs for O positive individuals, including ginger, kelp, and licorice, to support digestion, immunity, and thyroid function. While the theory lacks conclusive scientific evidence, these herbs are generally safe and known for various health benefits. Herbal teas and culinary spices are common ways to incorporate them.

Key Points

Blood Type O Diet Theory: Based on Dr. Peter D'Adamo's theory, the diet suggests that certain foods and herbs are more compatible with specific blood types, though this is not scientifically proven.
Digestive Aid Herbs: Ginger, licorice root, peppermint, and slippery elm are often recommended to support digestion and soothe the stomach in type O individuals.
Metabolic Support: Kelp is suggested for thyroid health due to its iodine content, while dandelion and parsley are beneficial leafy greens.
Immunity and Cardiovascular Health: Green tea and cayenne pepper are included for their antioxidant and anti-inflammatory properties, while hawthorn is noted for cardiovascular support.
Lack of Scientific Evidence: It's crucial to understand that major health organizations do not endorse the blood type diet due to insufficient scientific support. Many health benefits observed may stem from incorporating whole foods and general healthy habits.
Incorporate with Caution: Always consult a healthcare professional before adding new herbs or supplements, especially if you have existing health conditions or take medication, as some herbs can interact with treatments.

The blood type diet, developed by Dr. Peter J. D'Adamo, is based on the idea that dietary needs are influenced by a person's blood type. For Blood Type O positive, proponents of this diet suggest a high-protein intake and recommend specific herbs that may support overall health. These recommendations are not supported by mainstream scientific consensus, but many of the herbs mentioned are recognized for their general wellness properties. It is always advisable to consult a healthcare professional before making significant dietary changes or starting new supplements.

Herbs for Digestive Support

Individuals with blood type O are sometimes said to have more sensitive digestive systems. The following herbs are believed to offer digestive benefits, according to the blood type diet:

Ginger: Known for its anti-inflammatory properties, ginger may help soothe an upset stomach and aid digestion. It can be consumed as a tea or used as a spice in cooking.
Licorice Root: For type Os, licorice preparations are suggested to soothe the stomach lining, which may be beneficial given a perceived predisposition to ulcers. It is important to use licorice in moderation, as excessive amounts can have side effects.
Peppermint: Often enjoyed as a tea, peppermint can help calm digestive muscles and reduce bloating. It is considered a beneficial choice for blood type O individuals.
Slippery Elm: This herb can have a soothing effect on the digestive tract, potentially alleviating irritation. It is often taken as a tea or a supplement.

Herbs for Metabolic and Thyroid Health

Proponents of the blood type diet suggest that type O individuals may be more prone to thyroid issues. The following herbs are highlighted for their potential to support metabolic and thyroid function:

Kelp: A sea vegetable rich in iodine, kelp is recommended for type Os to help regulate thyroid function. It can be consumed in food or as a supplement.
Dandelion: The greens of this common plant are a beneficial vegetable for blood type O individuals and can be used in salads or teas. Dandelion is also known for supporting liver detoxification.
Parsley: This versatile herb is another beneficial food source for type Os and can be incorporated into many dishes.

Herbs for Immunity and Overall Wellness

Supporting the immune system is a general wellness goal, and some herbs are considered particularly helpful for blood type O individuals:

Green Tea: Considered beneficial for all blood types, green tea is a powerhouse of antioxidants. It can support immune function and metabolic health. Green tea is less oxidized than black tea, which is why it is often preferred.
Cayenne Pepper: A warming spice with anti-inflammatory benefits, cayenne pepper can be used to flavor meals and support circulation.
Hawthorn: This herb is recognized for its potential to support cardiovascular health. For type O individuals, who are said to benefit from a diet that supports the heart, hawthorn may be a valuable addition.

How to Incorporate Herbs into Your Diet

There are several easy ways to integrate beneficial herbs into your daily routine:

Herbal Teas: Brewing fresh or dried herbs into a tea is one of the simplest methods. Peppermint, ginger, and green teas are readily available and make excellent beverage choices.
Cooking and Seasoning: Using herbs like ginger, turmeric, garlic, and cayenne pepper to season meals is a great way to add flavor while enjoying their potential benefits.
Supplements: For specific needs, supplements containing kelp or other beneficial herbs are available. It is crucial to purchase from a reputable source and consult with a doctor before beginning any new supplement regimen.
In Salads: Fresh herbs like parsley and dandelion greens can be chopped and added to salads for a nutritional boost.

Comparison of Key Blood Type O Herbs


Herb	Primary Benefit	Recommended Form	Noteworthy Information
Ginger	Digestive support, anti-inflammatory	Tea, cooking spice	Can help with nausea and bloating.
Kelp	Thyroid and metabolic health	Supplement, seasoning	Rich in iodine, beneficial for thyroid regulation.
Licorice Root	Stomach soothing	Tea, supplement	Use in moderation; may soothe sensitive stomach lining.
Peppermint	Digestive calm	Tea	Soothes digestive muscles, reduces bloating.
Green Tea	Antioxidant, immune support	Tea	Minimally processed, rich in beneficial compounds.
Dandelion Greens	Detoxification, metabolic support	Salad greens, tea	Can be enjoyed as a leafy green vegetable.

The Scientific Perspective and Cautionary Note

It is essential to reiterate that the blood type diet and its specific recommendations are not backed by broad scientific evidence. A 2013 review of the blood type diet found no evidence to support its health claims. Some studies have indicated that people on the diets, regardless of blood type, might experience some health changes, but these findings are not conclusive. Experts often point out that the emphasis on whole foods and exercise within the blood type diet is likely responsible for any perceived benefits, rather than the blood type-specific food recommendations.

For individuals with pre-existing health conditions or those taking medication, some herbs can interact with treatments. For example, licorice root can affect blood pressure. Always consult a healthcare provider or a registered dietitian before incorporating new herbs or supplements into your routine, especially if you have a known health issue or are pregnant or breastfeeding. For more detailed information on the blood type diet's scientific standing, a comprehensive review can be found in The American Journal of Clinical Nutrition.

Conclusion

While the science behind the blood type diet is still debated, many of the herbs suggested for blood type O individuals offer general wellness benefits. Incorporating herbs like ginger, peppermint, and kelp into your diet can support digestion, thyroid health, and overall immunity. Whether you follow the blood type diet or simply seek to add healthy, flavorful ingredients to your meals, these herbs can be a beneficial addition. As with any dietary change, listen to your body and consult a healthcare professional to ensure safety and effectiveness.

Frequently Asked Questions

The blood type O diet, as proposed by Dr. Peter D'Adamo, is based on the idea that individuals with blood type O should follow a high-protein diet, similar to their hunter-gatherer ancestors. This includes consuming lean meats and specific vegetables while limiting grains and dairy.

Yes, proponents of the diet suggest several teas for blood type O. Beneficial options include green tea, ginger root tea, peppermint tea, licorice root tea, and slippery elm tea. These are thought to support digestion and overall wellness.

Kelp is recommended for blood type O individuals because it is a rich source of iodine. According to the diet's theory, this can help support thyroid health, which is considered a potential area of concern for this blood type.

No, the blood type diet is not scientifically proven. A 2013 review of the evidence found no studies supporting the claims of health benefits from following the diet based on blood type alone. However, many of the dietary principles, such as emphasizing whole foods, are generally considered healthy.

Yes, parsley is considered a beneficial herb for blood type O individuals and can be included in your diet. It is a versatile herb that can be added to many dishes and salads.

While not explicitly listed as harmful, some herbs should be consumed with caution based on general health advice. The blood type diet itself does not list many 'avoid' herbs, but overconsumption of certain herbs like licorice root can cause side effects like increased blood pressure. Always consult a healthcare provider.

Starting with teas is a simple way to incorporate herbs like ginger and peppermint. You can also use recommended culinary herbs and spices, such as ginger, garlic, cayenne, and turmeric, in your daily cooking to boost flavor and potential health benefits.