The idea is that by following a specific diet based on your blood type will improve digestion and cause weight loss.

According to this plan, which is from the books Eat Right 4 Your Type and Live Right 4 Your Type, each of the four blood types has a very detailed list of foods that must be avoided, based on the premise that blood type has its own unique antigen marker that reacts in a negative way with certain foods. You must purchase the book to figure out what you can and cannot eat. You also need to know your blood type.

Also, individuals have varying levels of stomach acidity and digestive enzymes, and these traits seem to be correlated with blood type. For example, people with type O blood are advised to eat a high-protein diet with no dairy products .

• Good if you like specific do/don't eat lists.
  
  
• Includes food amounts and how to time meals.
  
  
• Each type accounts for exercise and other lifestyle issues, such as stress.
  
  
• Restricted food intake will cause weight loss.
  
  
• Processed foods are discouraged.

• There is absolutely no scientific research that demonstrates a link between blood type, types of foods to eat, and body weight.
  
  
• You have to know your blood type.
  
  
• Unrealistic when family members have different blood types.
  
  
• Regardless of blood type, the plans are extremely complex and tough to stick with.
  
  
• Specific food groups eliminated, which can cause nutritional deficiencies.
  
  
• Recommends many supplements.