When it comes to blood type diets, there are four different types – A, B, AB, and O. Each diet is based on what substances are best for each blood type. Dr. Peter D’Adamo created this diet, and it is said to help manage weight, improve energy levels, and reduce the risk of illness. The diet is based on the theory that your blood type affects your ability to digest certain foods and that eating the right foods for your blood type can help you to be healthier. For example, those with type A blood should avoid meat and dairy, while those with type B blood should eat more green vegetables. Read on to know what is theorized to be the best O blood type diet.
Overview: What Is The Blood Type Diet?
The blood type diet was created by naturopathic physician Peter D’Adamo.
The premise of the diet is that your blood type determines what foods are best for you to eat, as well as which foods you should avoid.
There are four blood types – A, B, AB, and O – and each one has a different diet plan.
The diet is based on the theory that certain lectins (proteins found in food) are incompatible with certain blood types.
Lectins can supposedly cause problems like weight gain, bloating, and fatigue.
So by following the blood type diet, you can supposedly avoid these problems.
However, there’s no scientific evidence to back these claims.
The Different Blood Groups
Your blood group is inherited from your parents and falls into one of these four groups:
- O
- A
- B
- AB
Additionally, the presence of the Rhesus factor (that determines +ve or -ve) results in 8 different types of blood groups.
Some interesting facts about blood groups
- Most common: O+ve
- Least common: AB-ve
- Universal donor: O-ve
- Universal acceptor: AB+ve
Blood Type O: Profile
The O blood group is the only one that has antibodies for two antigens (A and B).
They appeared to have provided a unique survival advantage since many diseases that our ancestors developed have markers that simulated the A, B, and AB blood types.
Thus, O blood type has a useful defensive benefit.
However, this innate immunity can also increase the risk for certain conditions like ulcers and thyroid disorders.
O Positive Blood Type Facts
- O-positive is the most common blood type, with approximately 39-40% of the United States population having this blood type.
- Those with O-positive blood group can give blood to anyone with any positive blood group (O+ve, A+ve, B+ve, and AB+ve)
- O-positive individuals can receive blood only from O-positive or O-negative donors.
O Positive Blood Type Personality
- People with O-positive blood type are often described as daring, outgoing, and ambitious.
- They tend to be natural leaders with strong personalities.
- Individuals with O blood type are known for setting high standards for themselves and others. They exhibit characteristics such as confidence, determination, resilience, and intuition.
- Additionally, O blood types are often viewed as relaxed and peaceful in nature.
- This blood type is associated with individuals who are assertive and proactive in their approach to life.
O Blood Type Diet: What To Eat
O blood type can digest meals containing protein and fat.
Alkaline phosphatase and ApoB48 are two enzymes important for metabolizing fats and protein.
These enzymes are present in naturally higher levels in people of O blood type.
This ensures efficient metabolization of cholesterol in animal fats and better calcium assimilation.
O blood type diet, according to D’Adamo:
Animal Proteins
The O blood type diet allows the consumption of most meat products, including cold-water fish.
- Lamb
- Beef
- Mutton
- Mackarel
- Cod
Dairy
D’Adamo recommends avoiding dairy products. But the diet allows the occasional consumption of certain dairy products like
- Butter
- Certain types of cheese
Nuts and Seeds
Nuts are a great source of protein and good fats, both of which favor O blood groups.
- Walnuts
- Almonds
- Hazelnuts
- Pumpkin seeds
Vegetables
Most vegetables are allowed in this diet.
- Sweet potatoes
- Tomatoes
- Artichokes
- Parsley
- Parsnips
- Red pepper
- Garlic
- Horseradish
- Kale
(list is not exhaustive)
Fruits
Some recommended fruits include
- Grapefruits
- Figs
- Plums
- Most berries (except ones mentioned in “Foods to Avoid”)
Beans
The most beneficial beans for the O blood type diet include
- Adzuki beans
- Pinto beans
- Black-eyed peas
Grains
While most grains are prohibited in this diet, some may be included.
- Rice
- Millet
- Amaranth
- Buckwheat
The food can be seasoned with spices and condiments like iodized salt, cayenne pepper, parsley, curry, cocoa, and honey.
Allowed beverages include water, wine, club soda, and tea.
D’Adamo says the diet should also be paired with vigorous aerobic exercise.
He also recommends supplements that target digestive issues.
O Blood Type Diet: What Not To Eat
People with O blood type tend to have higher levels of stomach acid.
Further, a reactive protein called lectin present in many grains interferes with immune responses, which can lead to unwanted inflammation and autoimmunity.
Let’s have a look at the foods to be avoided for O blood type.
Animal Proteins
The diet plan for people with type O blood excludes
- Pork
- Pickled herring
- Smoked salmon
- Goose
- Octopus
- Caviar
Dairy
Except for the ones mentioned under “Food to Eat,” all other dairy products should be avoided.
Nuts and Seeds
Despite nuts being high in protein and good fat, some don’t make the cut to this diet.
- Cashew nuts
- Pista
- Brazil nuts
- Peanuts
- Poppy seeds
Vegetables
O blood group may not tolerate certain vegetables of the Brassica family like
- Cabbage
- Brussel sprouts
- Cauliflower
- Mustard greens
Nightshade family
- Eggplants
- Potatoes
Fruits
Specific fruits to be avoided include
- Oranges and tangerines
- Strawberries and blueberries
- Melons
- Avocado
- Rhubarb
Beans
The following beans should be avoided in this diet
- Kidney beans
- Lentils, including domestic, green, and red lentils
- Copper beans
- Tamarind beans
Grains
With the exception of the ones mentioned under “Food to Eat,” all other grains should be avoided.
While seasoning your foods, avoid species and condiments like pepper, mayo, tomato ketchup, vinegar, vanilla, pickles, nutmeg, and corn syrup.
Beverages to be avoided include beer, coffee, black tea, and distilled liquor.
Did you know that what you eat affects your gene expression and the gene variants you have to affect how you process the nutrients in your diet? These genetic variants also answer questions like why some people eat a lot and not put on weight, why certain people can’t consume dairy without experiencing gastrointestinal troubles, and why some people experience caffeine jitters after just one cup of coffee. Learn more:
Does The Blood Type Diet Work?
There’s no scientific evidence that proves the claims of blood type diets.
In fact, many studies have disproved the claims, and a few have reported health benefits unrelated to blood type.
The following aspects of the diet could contribute to the health benefits:
- Emphasis on eating vegetables and fruits
- Regular aerobic exercises
- Lowered triglyceride levels due to low-carb intake
However, these benefits are seen regardless of the blood type.
Risks Of Following A Blood-Type Diet
Despite some potential benefits, doctors and health experts are still apprehensive about it owing to the several drawbacks.
- Not backed by evidence: There’s no scientific root upholding blood-based diets. A review study reported that “no evidence currently exists to validate the purported health benefits of blood type diets.”
- Unproved effectiveness: No research supports the weight loss benefit of blood-type diets.
- Health complications: Emphasis on a high intake of animal proteins may lead to other health problems.
- Use of supplements: The diet can be quite restrictive and suggests that using dietary supplements can help people meet their nutritional needs. However, not all supplements may qualify as a proper substitute for a healthy and balanced meal plan.
Summary: O Blood Type Diet
| Food | Allowed | Not Allowed |
| Animal products | Any meat except the ones listed under “not allowed” | Pork Pickled herring Smoked salmon Goose Octopus Caviar |
| Dairy | Butter Certain types of cheese | All dairy products except the ones listed under “allowed” |
| Nuts & seeds | Walnuts Pumpkin seeds Almonds Hazelnuts | Cashew nuts Pista Brazil nuts Peanuts Poppy seeds |
| Vegetables | Any vegetable except the ones listed under “not allowed” | Brassica family Cabbage Brussel sprouts Cauliflower Mustard greens Nightshade family Eggplants Potatoes Shiitake mushrooms Fermented olives Alfalfa sprouts |
| Fruits | Grapefruits Figs Plums Most berries (except ones mentioned in “not allowed”) | Oranges and tangerines Strawberries and blueberries Melons Avocado Rhubarb |
| Beans | Any beans except the ones listed under “not allowed” | Kidney beans Lentils, including domestic, green, and red lentils Copper beans Tamarind beans Navy beans Pinto bean |
| Grains | Rice Millet Amaranth Buckwheat Kasha Kamut Rye Spelt Barley | All grains except the ones listed under “allowed” |
| Spices & condiments | Iodized salt Cayenne pepper Parsley Curry Cocoa Honey | Pepper Mayo Tomato ketchup Vinegar Vanilla Pickles Nutmeg Corn syrup |
| Beverages | Water Wine Club soda Tea | Beer Distilled liquor Black tea Coffee |
Reference
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742377/
- https://pubmed.ncbi.nlm.nih.gov/31308303/
- https://pubmed.ncbi.nlm.nih.gov/16412386/
- http://medicalnewstoday.com/articles/319303#eating-for-your-blood-type
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3497328/
- http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084749
- https://doi.org/10.3945/ajcn.113.058693
