Here's a part of a review of the diet you are describing. To me it sounds like a crock:What do the experts say?Medical experts universally agree that the theory is nonsense, and say there is absolutely no link between our blood group and the diet we eat. Consequently you won’t find qualified nutritionists or dietitians recommending this diet.There are also several concerns, namely that the diets recommended for blood groups O and A are considerably limited and cut out major groups of foods.In the long term, this can result in a poor intake of nutrients needed for good health. Cutting out dairy products, for example, will lead to poor intakes of calcium, which can put you at risk of osteoporosis (brittle bone disease), while avoiding meat can result in low intakes of iron, which can lead to anaemia. This is even more worrying in view of the fact that most people in the UK are blood group O or A.
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