Best Protein For B Positive Blood Type | What Science Shows

No scientific evidence supports the claim that people with B positive blood type need specific protein sources.

You may have heard that your blood type determines which foods your body handles well. The idea sounds almost intuitive — a simple test gives you a personalized meal plan. The “Blood Type Diet,” popularized by Dr. Peter D’Adamo in the 1990s, claims that type B people thrive as “nomads” and need a mixed diet with specific meats.

The honest answer is more straightforward: research shows any health improvements from following the diet likely come from eating a generally healthier diet, not from matching food to blood type. A 2013 systematic review in the journal PLOS ONE found no evidence to support the proposed health benefits of blood-type diets. So when people ask about the best protein for B positive blood type, the real answer involves protein quality, not ABO genetics.

How The Blood Type Diet Theory Works

The underlying theory suggests that lectins — proteins in food that can bind to blood cells — react differently depending on your blood type. The idea, as described by Harvard Health, is that your blood type is closely tied to your ability to digest certain foods, and that the right diet will improve digestion and energy.

Proponents claim people with type B blood evolved as nomadic herders and therefore do well with a varied, mixed diet. This is where the specific protein recommendations come from — lamb, goat, rabbit, turkey, and deep-sea fish like sardines and tuna are described as “beneficial.”

What The Recommendations Actually Look Like

According to the blood type diet, certain meats are thought to be favorable for type B while others should be avoided. The diet suggests that pork and chicken should be cut out, along with shrimp, crab, and shellfish. Dairy products like milk, cheese, and eggs are permitted in moderate amounts.

Why People With Type B Like The Idea

The blood type diet feels personal. A quick lab result gives you a list of foods — and for many people, having clear rules makes meal planning simpler. The theory suggests that type B people can eat a wide range of high-protein animal foods, which sounds more permissive than restrictive diets.

Proponents of the diet recommend these meats as ideal protein sources:

• Goat and lamb: Often listed as “highly beneficial” proteins for type B blood, with lamb being a staple recommendation across multiple sources.
• Turkey and rabbit: Lean poultry options that the diet suggests are well-tolerated, along with deer and other game meats.
• Tuna, sardines, and grouper: Deep-sea fish are considered favorable, while shellfish like crab and shrimp are flagged as problematic.
• Dairy and eggs: Moderate amounts of milk, cheese, butter, and eggs are included, with low-fat dairy often mentioned as acceptable.
• Soy and tofu: Plant-based protein options like soybeans and tofu also make the approved list for type B.

Some people who try the diet report feeling better, but per GoodRx, any improvements may come from simply eating more whole foods and fewer processed items — not from matching food to blood type.

What The Research Actually Shows About Type B Protein Needs

The strongest evidence on the blood type diet comes from a 2013 systematic review published in PLOS ONE, which searched medical databases for any trials testing the diet’s claims. The conclusion was clear: no evidence exists to support the proposed health benefits of blood-type diets. A large 2014 study reinforced this, showing that any benefits from following a blood-type diet were likely due to eating a generally healthy diet, not the blood type itself.

What does that mean for protein selection? The WebMD type B mixed diet page lists which foods the diet’s proponents classify as beneficial, but the site itself notes the theory remains unproven. Your body doesn’t care about your ABO blood type when digesting lamb or tofu — it cares about the protein quality, amino acid profile, and your overall dietary pattern.

The pattern is consistent: the recommended proteins are generally lean, nutrient-dense options that would be healthy for almost anyone. Lamb is rich in B vitamins and zinc. Turkey offers high-quality lean protein. Dairy provides calcium and vitamin D. These are good food choices — just not because of your blood type.

How To Choose Protein Based On Real Evidence

Focusing on protein quality rather than blood type gives you more flexibility and better science. Most healthy adults need between 0.8 and 1.6 grams of protein per kilogram of body weight, depending on activity level. The source matters less than the overall pattern.

Here’s a practical approach based on nutrition science, not ABO typing:

1. Prioritize complete proteins: Animal sources like meat, poultry, fish, eggs, and dairy contain all essential amino acids. Plant-based proteins can be combined for completeness.
2. Vary your protein sources: Rotating between red meat, poultry, fish, eggs, dairy, legumes, and tofu ensures a broader nutrient profile than sticking to just “approved” meats.
3. Consider your overall diet quality: A Healthline type B vs type A comparison shows the blood type diet recommends wildly different foods for each type — but there’s no mechanism explaining why the same meat would harm one person and help another based on blood type alone.
4. Watch for unnecessary restrictions: The diet tells type B people to avoid chicken, pork, and shellfish. These are healthy, affordable protein sources for most people, and cutting them out without evidence could limit your nutrient intake.

The Bottom Line

The blood type diet makes for an interesting story, but the evidence doesn’t support it. A 2013 systematic review found no proof that matching food to blood type improves health, and a 2014 study suggested any benefits come from eating better overall — not from the ABO connection. When choosing protein, focus on quality, variety, and what fits your actual health needs and preferences.

A registered dietitian can help you build a protein plan based on your individual goals, activity level, and any medical conditions — no blood test needed beyond basic protein adequacy.