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Should adults with ADHD have caffeine?

11 May 2017

Caffeine is the most commonly consumed stimulant. It provides an increase in mental focus (we like to believe) – like the cup of coffee before work for a boost of alertness or to fight fatigue during the day. Caffeine affects everyone differently and conditions like ADHD may interact with caffeine. While the right amount of caffeine can improve concentration, it can increase ADHD symptoms like hyperactivity and anxiety.

The caffeine effect

Caffeine, whether it’s in coffee, tea, chocolate or energy drinks can increase alertness and energy. It stimulates the sympathetic nervous system which affects the body and brain. It also increases the brain’s levels of dopamine and norepinephrine. These two chemicals are important for focus and concentration which can be lacking in people with ADHD – so it can assist to some degree.
But because caffeine is a stimulant, it can aggravate ADHD symptoms. For example, it can reduce sleep or disrupt sleeping patterns. In turn, sleep deprivation worsens ADHD-like symptoms like irritability, forgetfulness, lack of concentration and difficulty controlling emotions.

ADHD medication and caffeine

According to research, heavy caffeine intake is about 500 to 600 mg per day. Adults with ADHD don’t have to give up caffeine completely, but moderation is key to ensure an ADHD treatment plan works effectively and symptoms are managed.  People taking both ADHD medication and caffeine might get a greater stimulant effect. Adults with either diagnosed or undiagnosed ADHD can have adverse health implications like rapid heartbeat or muscle shakes or tremors with even small amounts of caffeine.

The safety limit

Adults with ADHD can be more sensitive to caffeine and it’s hard to determine an exact safe caffeine limit. Some can have one cup of coffee (100mg-200mg) in the morning and still struggle to sleep in the evening – this is well after the caffeine’s effects should have worn off. If you have ADHD, have a minimal dose of caffeine in the morning and avoid caffeine consumption in the evenings – or even after midday. It’s important to track how many highly-caffeinated drinks and foods you have each day. Monitor what happens to your body and brain after you do, and manage caffeine depending on the effects. If caffeine has a negative effect, try and replace it with an alternative. If you grapple with afternoon slumps, perhaps replace big lunches with smaller meals and snack throughout the day. Go for a walk to refresh your body and brain and drink more water when tempted to have caffeine. Caffeine is a diuretic (causes fluid loss) and when we’re fully hydrated, our bodies crave less caffeine.

Hidden caffeine

If you’re trying to cut back, be aware the sneaky stimulant is present in unexpected foods and drinks. The Food and Drug Administration (FDA) doesn’t require manufacturers to list caffeine content on nutrition labels, so it’s often hard to tell whether a product contains the stimulant, and how much. There’s hidden caffeine in foods like decaf coffee, ice-cream, sunflower seeds, instant oats and even some pain medications. Some people find caffeine helps alleviate the symptoms of ADHD, while others find it doesn’t offer any benefit at all, or makes symptoms worse. Pay attention to your body and work with your healthcare practitioner to find out what’s best for you.

For more information around the symptoms, impact and treatment of ADHD, visit:


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