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Ashleigh Willis M.Res
Ashleigh Willis M.Res

How Nootropics Boost Mental Clarity and Focus

6 research-backed supplements to sharpen the mind.

In recent years, nootropic supplements and ‘smart drugs’ have exploded into the mainstream consciousness. There are numerous companies and ‘neurohackers’ who tout various substance as the key to better academic performance and a higher IQ.

There exists a myriad of nootropic substances which can benefit cognition, learning and mental clarity – but can they really increase our IQ as some companies claim?

What are nootropics?

Nootropics’ refer to a broad range of supplements and compounds which can be taken to enhance brain function and health. The term encompasses everything from man-made synthetic compounds, nutrients, vitamins, minerals and neurotransmitter precursors.

Unfortunately, claims that nootropic supplements will actually increase your IQ are misleading. Nootropics won’t alter your IQ or intellect. However, what some nootropics can do is powerfully impact brain function.

Nootropics can modulate a range of biological processes which aid with neurotransmission, intracellular signalling and various molecular processes. Subsequently, this can improve cognition, memory and learning. Many nootropics can also improve the production of proteins which offer neuroprotection and foster brain health.

1. Citicoline: The Focus Enhancer

Citicoline (sometimes known as CDP-choline) is a naturally occurring molecule that is vital for key neuronal functions, particularly those related to cognition, learning and memory. This is because citicoline is quickly converted into choline once in the body.

Choline is a key precursor molecule which is used to synthesise the neurotransmitter Acetylecholine (Ach).

Acetylcholine is a key player in attention and alertness, it also underlies many complex behaviours 1, 2. The cholinergic system of neurons is widely implicated in various aspects of cognition, learning and memory 3-5.

Citicoline has become a hot topic in the field of neuroscience. Indeed, some countries have already trialled the supplement to aid with cognitive and mental function during stroke recovery 6-8.

The good news is that, unlike some other nootropic substrates, citicoline has been the subject of fairly rigorous scientific investigation. This means we have a good understanding of its effects, efficacy, safety and best use.

Studies in humans have highlighted that citicoline can have a beneficial effect on concentration, working memory and attention.

In 2015, researchers showed that a 28-day period of citicoline supplementation improved the performance of adolescent males on a range of attention and psychomotor speed tasks 9.

Similarly, a 2014 randomized, double-blind, placebo-controlled study indicated that healthy adult men who received a citicoline-supplemented caffeinated beverage outperformed controls on a range on cognitive tests.

The citicoline-caffeine beverage improved sustained attention, reaction time and memory 10. The researchers supported these behavioural results with analysis of electrical activity in the brain. They showed that the citicoline-supplemented group had patterns of activity which strongly indicated improved attention.

A 2008 study which investigated the effects of citicoline in 16 healthy human participants demonstrated that citicoline supplementation improved frontal lobe bioenergetics.

Importantly, they showed that metabolism, energy reserves and energy utilisation were improved in key areas of the cortex which are associated with learning, memory and executive function.

Though a small study, this potentially shows that citicoline increased the production of components essential to build and maintain cell membranes. This means citicoline may protect our neurons from age-related damage and decline 11.

2. B Vitamins: Better Brain Health for Boosted Cognition

B vitamins are at the heart of good health. These vitamins are vital for a number of crucial cellular processes and, without them, both our brain and body can suffer.

When it comes to cognitive performance, there are a couple of key B-vitamins that we’ve got to ensure we have enough of in order to maintain optimal cognitive performance. The most notable of these are:

  • Thiamine (B1)

Thiamine (or vitamin B1) is an essential component of mitochondrial metabolism. As we all learned in biology 101, mitochondria are the ‘powerhouses’ of our cells which produce the energy molecules required to full our cells.

Thiamine also serves as a co-factor which helps to produce the enzymes required for the production of numerous neurotransmitters 12.

Research has highlighted that thiamine deficiencies can be extremely detrimental to brain function. In particular, prolonged deficiency can lead to reduced cognitive capacity and increased neuronal death 13.

Animal studies now suggest that thiamine may play a role in the regulation of the primary excitatory (glutamate) and inhibitory (GABA) balance of the brain 14. These two neurotransmitters work in concert to produce a balanced amount of neural activity.

Any deviation in the levels of GABA or glutamate can induce a variety of problems, including psychiatric disorders to cognitive impairments.

Importantly, a 2010 study in rodents showed that consistent thiamine deficiency during development leads to sustained cognitive impairment 15.

Many people report a noticeable improvement in mental clarity and energy after supplementing with B1.

  • Cobalamin (B12)

Cobalamin (or vitamin B12) has some hefty responsibilities in our brains. The vitamin is known to be essential for the synthesis of DNA and RNA which control the production of key proteins and neurotransmitters.

Additionally, research has shown the importance of B12 in the regulation and maintenance of the fatty substance called ‘myelin’ which surround the axons that neurons use to communicate 16.

These myelin sheaths enable electrical signals to be propagated quickly between neurons. Hence, the stronger the myelin sheath, the quicker or neurons can relay messages to each other. The net result of this speedy communication is improved mental agility and speed.

Cobalamin has also been shown to aid in regulating key neurotransmitters such as serotonin, GABA and dopamine 17,18. This balances mood, reduces anxiety, enables mental clarity and allows us to use our full cognitive capacity 19.

It’s important to ensure we maintain optimal levels of B12, as research has shown that even a mild deficit can result in accelerated cognitive decline 20-22.

3. L-Tyrosine: A Cognitive Flexibility Boost

L-tyrosine is an amino acid which is a vital precursor to catecholamine neurotransmitters (such as dopamine and epinephrine). L-tyrosine can exert a particularly strong nootropic effect on mood because of its enhancement to levels of the molecule L-DOPA, the precursor to dopamine.

The neurotransmitter dopamine is critically linked with stable mood, so supplementing with L-tyrosine may offer a mood-boosting benefit. However, there’s more to dopamine than improved mood.

A double-blind, randomised, placebo-controlled study conducted in healthy adult men showed that supplementing with L-tyrosine substantially improved cognitive flexibility 23.

Cognitive flexibility is the ability to quickly switch between thinking about different concepts or to think about multiple concepts simultaneously. Participants were profoundly more capable of task switching with less cognitive resource depletion when supplemented with tyrosine. These results are also supported by animal studies 24.

Supplementing with L-tyrosine is likely to enable you to task switch throughout the day with ease… Perfect for anyone working on multiple projects.

Some studies have also indicated that L-tyrosine can improve memory and cognition when the brain is under-going short term stress 25.

That means that supplementing with L-tyrosine before you perform in a potentially stressful situation (perhaps, public speaking or business meetings) could improve your cognitive capacity… Hopefully helping us to avoid those dreaded ‘mind-blank’ moments!

4. L-Theanine: A Calm and Clear Mind

L-theanine is a naturally occurring amino acid which can be found in green tea.

Animal models have shown that L-theanine can improve memory and ameliorate cognitive deficits in animal models of Alzheimer’s disease 26-28.

Some studies have suggested that the molecule may be beneficial for relaxation and anxiety reduction 29,30. While it may not quite meet the grade for an anti-anxiety medication according to some clinical studies 31, many patients with generalised anxiety disorder do report improvements after taking the supplement.

Animal studies also suggest that L-theanine may regulate levels of serotonin, GABA and dopamine 32, all of which can help to balance mood.

Ultimately, this calming effect allows clarity of mind which can improve our performance and ability to concentrate on mentally strenuous and intellectual tasks.

This idea is supported by research which demonstrates L-theanine to enhance alpha frequency brain-waves which are associated with relaxed attentional processing 33.

L-theanine also appears to improve sleep, in particular a restorative form of NREM sleep 34.

Sleep, especially NREM, is vital for memory consolidation, daytime cognitive capacity and alertness. Any supplement which can improve this part of the sleep cycle is likely to have subsequent benefits to mental ability, learning and memory.

5. Caffeine: Kickstart Alertness & Memory

Americano, latte, espresso, cappuccino… We all have our own favourite caffeine-laden beverage of choice. Caffeine is the most widely used psychoactive compound worldwide.

Most of us consume caffeine daily to boost our alertness, so it seems intuitive that caffeine is now classified as a nootropic substance. Caffeine alertness boosting effects, improvement to physical endurance and high bioavailability make it a great candidate for supplementation.

Interestingly, at a cellular level, caffeine has been suggested to play a role in learning and memory by modulating some forms of synaptic plasticity. Enhanced synaptic plasticity can enable improved memory and learning 35.

The effects of caffeine can be beneficial for our cognition and alertness. However, for some of us, the substance can be anxiety-inducing and cause difficulty with sleep.

However, nootropic stacks which combine caffeine with L-theanine can circumvent these effects. L-theanine can reduce the negative effects associated with caffeine while allowing us to reap the cognitive benefits of the supplement 36-39.

6. Rhodiola Rosea: Protect, Repair, Regenerate

Rhodiola Rosea is an adaptogenic herb which has been historically used in traditional Russian and Scandinavian medicine. More recently, Rhodiola Rosea has earned the title of ‘nootropic’ due to the claimed benefits of the herb on fatigue, concentration and memory.

While there is currently less clear evidence on the efficacy of this nootropic, there are some hopeful findings in the literature.

A 2012 meta-analysis reported that there may be some beneficial effects of Rhodiola Rosea on mental fatigue and physical performance 40. However, it is important to note that many of these studies do require more rigorous reporting and consistent experimental design.

None-the-less, accounts from regular users claim that the supplement helps to improve focus, balance mood and enhance alertness.

Where do I start with nootropics?

The landscape of neurochemistry and nootropics can be difficult to navigate. Seasoned ‘neurohackers’ often compose their own ‘stacks’ of nootropics; choosing to combine various substances and make their own decisions on dosages and frequency.

However, when it comes to neuromodulation, you’ve got to know what you’re doing!

Luckily, there are reputable formulations which have been created in the hands of neuroscientists and pharmacologists. This is the most recommendable route for nootropic beginners, as these pre-made stacks have been designed with safety and effectiveness in mind.

As with any supplement, it’s always important to make sure you’re obtaining these from a reputable source. Moreover, it’s advisable to seek advice from experts and medical professionals before making any major changes to your supplementation routine.

Now, with all that said – happy neurohacking!


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About the Author
Ashleigh Willis M.Res

Ashleigh Willis is completing her doctoral degree (Ph.D.) in neuroscience, researching the molecular underpinnings of neurodevelopment and psychiatric disorders.