This held true for all eight subjects. Another study published in the 1999 edition of the American Journal of Clinical Nutrition argues somewhat against D'Adamo's claims about the negative effects of peanuts on some blood types. For instance, D'Adamo states that Type B should avoid most all nuts, especially peanuts. The consumption of peanuts by Type B would result in the agglutination process and interfere with the homeostasis of bodily systems. The study mentioned above was on the effects of peanuts as part of a heart-healthy diet.
Nuts are low in saturated fatty acids and high in monounsaturated and polyunsaturated fatty acids.
Evidence also suggests that they contain other bioactive molecules that have a cardio protective effect. These bioactive components include plant protein, dietary fiber, and micronutrients such as copper and magnesium. This study demonstrated the benefits of nuts to heart health. The question that remains is whether or not this cardiovascular benefit outweighs the proposed inhibited metabolism for Type B's who consume nuts. D Adamo also puts forth limitations on the types and amounts of vegetables each blood type should consume.