Given that the erythrocytes of blood type 0 do not contain any components which may interfere with the components of other blood types, those having this blood type can donate blood to anyone. However, these people can receive blood from the same group only.

Obviously, this blood type is quite specific and different from the rest. People with blood type 0 are more susceptible to infections but possess features which make them extraordinary at the same time.

Namely, these people are meant to be leaders and born to take professional action. They are successful, focused, and considered as capable individuals.

However, as mentioned above, they are more susceptible to certain health issues, such as hypothyroidism, ulcers, thyroid issues, and iodine deficiency.  The deficiency in iodine is associated with water retention and higher risk of developing obesity.

Interestingly, in Japan this blood type is associated with specific identity.  This is the reason why potential workers are always asked about their blood type when on job interview.   These people are seen as composed, engaged, careful, devoted, and capable. Due to the fact that their ancestors were great hunters with ability to evaluate and higher chances to survive, they are depicted as smarter and better students when compared to others.

HYPERACTIVE AND IMPRUDENT

Anxiety is their enemy number one, since it makes them hyperactive and imprudent. Moreover, poor diet and lack of physical activity makes them prone to insulin resistance, poor thyroid function, obesity, and other health issues.They are at higher risk of getting ulcers and stomach problems than others, due to the greater amount of stomach acid they deal with.

This is why they should avoid alcohol and caffeine at all cost. Caffeine increases adrenaline, which his already high in people with this blood type.

These people are recommended to engage in some physical activity and stick to it! The best would be to exercise 3-4 times a week.

It is also important to mention that another factor that differentiates type O from the rest is the stress hormone cortisol.  Type O produces the least amount of this hormone compared to type A that produces the most amount.  When cortisol is over-produced on the long run, it can lead to adrenal exhaustion and development of symptoms of fatigue and depression.  The reaction to stress in people with type O cause an overproduction of adrenaline, which in turn makes these people more prone to anxiety when stressed.