The first Asian nomads are your ancient ancestors if you have B-positive or B-negative blood, claims Peter J. D'Adamo, the creator of the blood type diet. According to D'Adamo, following a diet that restricts or eliminates the foods these nomads would not have eaten will help a person with type-B blood lose weight, feel more energetic and avoid medical problems. In 2014, a study published in "Plos One" concluded that there is no evidence to support the premise underlying the blood type diet. Before you start any part of the plan, talk to your doctor.
Stay Away from Wheat
A person with B-positive blood is told to avoid all forms of wheat on the blood type diet, including whole-wheat bread products, durum wheat products, bulgur, wheat germ, wheat bran, shredded wheat and cream of wheat. Consuming wheat will supposedly increase the chance of diabetes and weight gain. In addition, type-B people should avoid buckwheat, rye, couscous, soba noodles, wild rice and cornmeal.
Chicken, goose, duck and quail are not recommended for type-B individuals, as D'Adamo claims that chicken in particular contains compounds that can increase a type-B person's risk of immune problems and stroke. While lamb, venison, mutton and some types of fish are recommended, the blood type diet also discourages people with B-positive blood from consuming any type of pork, anchovies, striped bass, octopus, smoked salmon and shellfish like mussels, shrimp, oysters and lobster.
Pick Dairy Carefully
Unlike the diet advice given to type-A and type-O people on the blood type diet plan, type-B people are allowed dairy products in moderation, including cow's milk, eggs, buttermilk and cheeses such as cheddar, Swiss, Monterey jack and Brie. But they are instructed to avoid ice cream and three specific types of cheeses: string cheese, blue cheese and processed American cheese.
Limit Plant-Based Protein
Certain plant-based proteins should be considered off-limits for people with type-B blood, contends D'Adamo. These include peanuts, which he says will inhibit the liver and cause a drop in blood sugar, as well as sesame seeds and lentils, which allegedly prevent proper nutrient absorption in type-B individuals. Cashews, pistachios, black-eyed peas, pinto beans, black beans, pumpkin seeds, sunflower seeds and tofu are examples of other restricted foods.
Watch Out for Certain Produce
D'Adamo encourages people with B-positive blood to enjoy a variety of fresh fruits and vegetables but cautions them to steer clear of pomegranates, coconuts, rhubarb, all types of olives, artichokes, radishes, tomatoes, avocados, pumpkin and mung bean sprouts. Corn, which D'Adamo says will slow a type-B person's metabolism and increase his risk of diabetes, should be particularly avoided.
Skip the Soda
The blood type program advises all people to eliminate or restrict processed and commercial foods from their diets, but it especially warns type-B individuals to avoid consuming carbonated beverages, including club soda, regular or diet cola and seltzer water. They are allowed to consume beer and wine in moderation but should not have distilled liquor while following the plan.