What is the Theory Behind the AB+ Blood Type Diet?
The blood type diet, popularized by naturopathic physician Dr. Peter D'Adamo, is a dietary and lifestyle plan that suggests individuals should eat foods that align with their blood type. For individuals with AB blood type, D'Adamo refers to them as the 'enigma' or 'enigma blood type'. This is because the AB blood type is the most recent to evolve and is a blend of A and B blood types, supposedly combining their dietary characteristics.
According to the theory, people with AB blood have lower stomach acid, similar to Type A individuals, but also possess the Type B adaptation to meats. This combination, it is claimed, can make it difficult for them to metabolize meat efficiently, causing it to be stored as fat. The diet is built on the concept that certain food proteins called lectins can react with a person's blood type antigens, causing issues such as fatigue, poor digestion, and disease.
It is important to note that the scientific community widely refutes the blood type diet. Multiple studies, including systematic reviews, have found no compelling evidence to validate its claims. Any observed health benefits often come from adopting a healthier diet overall, such as eating more whole foods and fewer processed items, regardless of blood type.
Meats and Seafood to Limit
For those following the blood type diet, specific recommendations are made regarding protein sources for the AB blood type due to the purported low stomach acid.
- Beef and Pork: Red meat is generally discouraged because of the theory that people with AB blood cannot efficiently digest it, leading to potential health issues.
- Chicken: Although it is a lean meat, some versions of the blood type diet suggest avoiding chicken, though recommendations can vary. This is based on the theory that lectins in chicken may not be beneficial for this blood type.
- Smoked or Cured Meats: Processed meats, such as sausages, bacon, and hot dogs, are on the list of items to avoid due to their processing methods and potential for inflammation.
- Shellfish: Certain seafood like shrimp, crab, and shellfish should be avoided or limited according to some versions of the diet.
Grains and Legumes to Avoid
Some grains and legumes are also targeted for avoidance due to concerns about lectins and their effect on digestion for the AB blood type.
- Corn and Buckwheat: These are considered harmful to individuals with AB blood and should be avoided entirely according to the theory.
- Kidney Beans: These legumes are typically listed as foods to avoid for the AB blood type.
- Wheat: The diet suggests limiting or avoiding wheat and wheat-based products.
- Sesame Seeds and Sunflower Seeds: These seeds are often recommended for avoidance under the blood type diet guidelines.
Dairy, Beverages, and Other Foods to Avoid
While some dairy is considered acceptable for AB types, others, along with certain beverages and foods, are on the avoidance list.
- Full-Fat Dairy: While yogurt and kefir may be acceptable, full-fat dairy and aged cheeses are often discouraged.
- Caffeine and Alcohol: The diet claims individuals with AB blood should avoid caffeine, alcohol, and certain stimulating beverages to prevent digestive issues and other health problems.
- Bananas and Oranges: Certain fruits like bananas and oranges are mentioned as fruits that are better to avoid for this blood type.
- Refined Sugars and Processed Foods: As with most healthy eating plans, processed foods, refined sugars, and artificial ingredients are advised against.
Scientific Context and Alternatives to the Blood Type Diet
Despite the specific and detailed recommendations, the blood type diet is not supported by mainstream medical science. The theory that blood type should dictate diet is not based on sound nutritional science, and the claims about lectins and their specific interaction with different blood types have been largely debunked.
Instead of focusing on blood type, the general consensus among health professionals is that a balanced, varied diet is most beneficial for overall health. Here is a comparison of the blood type diet for AB+ and evidence-based nutritional guidelines:
| Feature | Blood Type Diet (for AB+) | Evidence-Based Nutrition Guidelines |
|---|---|---|
| Principle | Diet is dictated by blood type and ancestral genetics, focusing on lectin compatibility. | Diet is based on well-established nutritional science, individual health needs, and overall balance. |
| Food Restrictions | Avoidance of specific healthy foods like corn, kidney beans, and wheat, regardless of individual tolerance. | Restrictions are based on individual allergies, intolerances, or specific health conditions, not blood type. |
| Meat Consumption | Limits meat portions and restricts certain types like beef and chicken due to low stomach acid claims. | Encourages lean protein sources like chicken, fish, and legumes, with red meat limited for heart health. |
| Focus | Highly specific and restrictive rules based on a debunked theory. | Promotes whole, unprocessed foods, fruits, vegetables, and lean protein for everyone. |
It's worth emphasizing that any positive results seen from following the blood type diet are likely due to its broader, generally healthy recommendations, such as reducing processed foods and sugars. A more prudent approach for health and wellness is to consult with a registered dietitian or healthcare provider who can provide personalized, evidence-based nutritional advice.
Recommended Approach to Diet
Rather than adhering to the scientifically unsubstantiated blood type diet, a more effective and sustainable approach to healthy eating involves focusing on a balanced, nutrient-dense diet. This includes a wide variety of foods from all food groups while minimizing processed items.
Here are some general, scientifically supported dietary recommendations:
- Whole Grains: Incorporate diverse whole grains such as brown rice, oats, and quinoa into your diet for fiber and nutrients.
- Lean Proteins: Choose from a wide array of lean protein sources, including chicken, fish, beans, lentils, and tofu, to support muscle health.
- Fruits and Vegetables: Fill your plate with a variety of colorful fruits and vegetables, as they are rich in vitamins, minerals, and antioxidants.
- Healthy Fats: Include sources of healthy fats like olive oil, avocados, nuts, and seeds to support brain and heart health.
- Mindful Eating: Pay attention to portion sizes and eat mindfully to foster a healthy relationship with food.
Conclusion
The question of what foods should AB+ blood type avoid? leads to a discussion of the blood type diet, a theory that lacks scientific support. While proponents suggest avoiding foods like corn, beef, and processed meats, the reasoning behind these restrictions—based on blood type genetics and lectin interactions—has been widely refuted by the scientific community. Any health benefits experienced by followers are more likely attributable to the diet's general promotion of healthier eating habits, such as reducing processed foods. A balanced, varied, and evidence-based approach to nutrition, guided by a healthcare professional, remains the most reliable path to achieving optimal health. Focusing on a nutrient-dense diet rich in whole foods is beneficial for everyone, regardless of their blood type.
For more information on evidence-based dietary recommendations, consider reviewing the guidelines from authoritative health organizations.
