Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that affects millions. In this article, Ability Central will dive into eight things you need to know about ADHD, including:

• What is ADHD?
• Can ADHD affect communication?
• What causes ADHD?
• What role does sugar play in ADHD?
• At what age is ADHD most often diagnosed?
• How often do adults have undiagnosed ADHD?
• Does ADHD occur more in boys than in girls?
• Is ADHD more prevalent in one race or ethnic group than another?

What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a highly genetic, brain-based neurodevelopmental disorder. It affects executive functioning skills, including:

• Attention
• Concentration
• Memory
• Motivation and effort
• Learning from mistakes
• Impulsivity
• Hyperactivity
• Organization
• Social skills

Without proper identification, diagnosis and treatment, ADHD can have potentially serious consequences, including:

• School and career difficulty
• Family stress and disruption 
• Depression
• Relationship problems
• Substance use issues
• Accidental injuries
• Reduced life expectancy

Can ADHD affect communication? 

The distractions, impulsiveness, and difficulty with paying attention brought about by ADHD can affect communication, resulting in interruptions, disorganized thoughts, and trouble following conversations.

These communication difficulties can have a profound effect on a person's quality of life and can impact their ability to work, socialize, and maintain relationships.

What causes ADHD?

ADHD is often believed to be passed down from parent to child through genetics. In fact, at least one-third of all fathers who had ADHD in their youth have children with the condition. In addition, a large majority of identical twins with ADHD share the trait with their twin.

Beyond genetics, scientists are studying other possible causes and risk factors for ADHD, including:

• Brain injury
• Exposure to environmental risks during pregnancy or at a young age
• Alcohol and tobacco use during pregnancy
• Premature delivery
• Low birth weight

What role does sugar play in ADHD?

Despite popular myths, research shows that none of the following cause ADHD:

• overeating sugar
• watching too much television
• parenting
• social and environmental factors such as poverty or family chaos 

There is, however, a strong link between a high intake of refined sugar or saturated fat and an increase in ADHD-like symptoms.

At what age is ADHD most often diagnosed?

ADHD symptoms start before age 12; in some children, they're noticeable as early as 3 years of age. 

The average age of an ADHD diagnosis is 7 years of age, but this varies by the severity of symptoms. For milder symptoms, the average age of diagnosis is 8 years old; for moderate symptoms, the average age is 7 years old; and for severe symptoms, the average age is 5 years old.

How often do adults have undiagnosed ADHD?

ADHD diagnoses among adults are growing four times faster than are ADHD diagnoses among children in the United States. Even still, it is estimated that fewer than 20% of adults with ADHD are currently diagnosed.

The reason for the difficulty in diagnosing adults is that the diagnostic criteria for ADHD were designed to identify it in children, not adults. In addition, 93% of adult psychiatrists say they have never had any ADHD training, either in their residency or their continuing medical education, whether in children, adolescents, or adults. 

Does ADHD occur more in boys than in girls?

In childhood, boys are more than twice as likely to have an ADHD diagnosis as girls (12.1% of boys compared to 5.5% of girls). In adulthood, however, that gap drastically decreases as 5.4% of men are diagnosed with ADHD versus 3.2% of women.

Many women report not knowing they have ADHD until they’re in their 30s or 40s.

Is ADHD more prevalent in one race or ethnic group than another?

Racial disparities in the diagnosis and treatment of childhood ADHD is evident in recent studies. At age 4, the diagnosis rate was about the same across all races and ethnicities. By age 12, an ADHD diagnosis was given to:

• 14% of white children
• 12% of Hispanic children
• 10% of Black children
• 6% of Asian children

Among adults, while cases among all ethnic groups are increasing, white people were most likely to get diagnosed. 

To learn more about ADHD, check out Ability Central’s full line of resources, including:

• Attention Deficit Hyperactivity Disorder (ADHD) in Adults: Symptoms 
• Attention Deficit Hyperactivity Disorder (ADHD) in Adults: First Steps
• Attention Deficit Hyperactivity Disorder (ADHD) in Adults: Support Options