This is also the case for some mixed-race people of African or African Caribbean descent.
Experts aren't sure why these conditions are more common in people of African and African Caribbean origin, but they think it may be linked to diet, lifestyle and different ways of storing fat in the body.
There are several ways to reduce your risk of these conditions.
Find out how to protect yourself against:
People from African and African Caribbean communities are more likely than others to be admitted to hospital for mental illness. The same is also true for people of white and black mixed ethnicity.
Most of us have problems at some time in our lives, such as money worries, stress at work or the death of a loved one, which can affect our mental health.
But people from African and African Caribbean communities can face additional problems that may affect their mental health.
Everyday life has a big impact on mental health, and black communities in the UK are still more likely than others to experience problems such as bad housing, unemployment, stress and racism, all of which can make people ill.
Worldwide, it seems people who move from one country to another have a higher risk of mental illness. This is especially true for black people who move to predominantly white countries, and the risk is even higher for their children.
While mental illness is no more common in Africa or the Caribbean than it is in the UK as a whole, it's a bigger problem for African and African Caribbean communities living in the UK.
Our section on mental health has information on where to go for help and support, and what you can do to maintain good mental health.
healthtalk.org has interviews and videos of people talking about their experiences of mental health issues – see mental health: ethnic minority experiences.
Sickle cell disease
Sickle cell disease (SCD), sometimes called sickle cell, reduces the blood's ability to carry oxygen around the body.
It developed thousands of years ago in countries where malaria was common, and today it mainly affects people of African and African Caribbean origin.
SCD can also affect people from Mediterranean, Middle Eastern and Asian communities. The most common type of SCD is sickle cell anaemia.
People can be carriers of sickle cell disease without knowing it. If you're thinking of starting a family, it's important to get tested to see if you carry the gene.
Our section on sickle cell disorder provides information about the disease, including symptoms and screening, and links to where you can get more help and support.