Eat for your blood type "Does It Work? Only one study has looked at this kind of diet. It found that people with certain blood types got more of a cholesterol-lowering benefit from eating a low-fat diet. But it didn't prove that the Blood Type Diet was responsible for this effect or that it works for weight loss. It's likely that you would lose weight, though, because the diet can be very restrictive." Eating for your blood type A+ & A- "Blood Type A+ & A-.. "