Exam Season: Supplements To Support Brain Power, Sleep And Stress

Key nutrients to hack sleep, stress and cognitive performance.

Exam Season: Supplements To Support Brain Power, Sleep And Stress photo

Exams – the very word strikes fear into the heart of the best of us! Whether it’s handling revision, managing nerves or mastering subject topics and techniques, exam season makes demands on the brain and nervous system that go way beyond everyday requirements. Exam days themselves require sustained bursts of peak performance in concentration, memory, evaluation, problem-solving, reasoning, decision-making, organisation and presentation.


How do you support good physiological function in these areas to give yourself the best chance of exam success? In this article we look at some fundamental supplements that might help keep stress at bay, optimise sleep and keep the brain running well. We also explore the exciting world of nootropics – supplements that are increasingly showing promise in enhancing cognitive capabilities.


1. Power to the Brain!


Nutrients for brain power: what are the essentials?

The brain is the most metabolically active organ in the body, using 20% of our energy.1 A range of vitamins, minerals and other nutrients act as chemical catalysts to support these metabolic processes and provide the building blocks for the brain and its messenger system of nerves, hormones and neurotransmitters. A good supply of nutrients is therefore essential for effective cognitive processing, including learning and recall. Research suggests that B vitamins, vitamin D, fatty acids and amino acids (proteins) are the key nutrients that work in synergy to keep this complex system running optimally.2


Let’s take a closer look at these four essentials:


B Vitamins

The eight water-soluble B vitamins come into play at multiple points in the metabolic processes of the brain and nervous system. The B vitamins are so important that each one has its own doorway into the brain across the blood-brain barrier!3 Look out in particular for these brain superstars:


  • Vitamin B12 – adequate levels of this vitamin are crucial for maintaining cognitive processing power and regulating the nervous system.4 Vitamin B12 supports the production of neurotransmitters, accurate cell replication and the integrity of the myelin sheath that surrounds nerves. Testing of your serum B12 levels is a useful place to start when supplementing this important vitamin, especially for vegans and vegetarians as vitamin B12 is only available in animal-derived foods. One of the most bioavailable vitamin B12 supplements is hydroxocobalamin.5
  • Vitamin B9 (folate) – vitamins B9 and B12 work synergistically to process homocysteine, a neurotoxic and excitatory chemical produced as a by-product of metabolism (6). Sufficient folate intake is therefore needed to keep homocysteine at safe levels for the brain.2 Look for supplements containing the bioavailable “folate” rather than “folic acid”.7

Vitamin D3

Vitamin D has antioxidant and anti-inflammatory effects in the brain, protecting it from everyday damage (8). Research also suggests that vitamin D is:


  • Vital for maintaining signalling pathways used in memory and cognition.2
  • Stimulates the growth of neurites, the sites of growth on brain cells (neurons).9
  • Regulates nerve growth factor, the substance needed for survival of neurons in the hippocampus and brain cortex,9
  • Associated with larger brain volume and healthy white matter.2
  • Essential for clearance of amyloid, the protein substance found in the brain in Alzheimer’s disease,8

Essential fatty acids

Sixty percent of the brain is made up of fat, underlining the importance of maintaining a good supply of appropriate fatty acids for the brain’s maintenance and repair.10 Two kinds of fatty acid have attracted the most attention for their use as supplements to support good brain and nervous system function:


  • Omega-3 oils – derived from marine sources, these long-chain fatty acids are incorporated in cell membranes and, in particular, the sheaths surrounding nerve cells (11). The quality of neuronal membranes maintains brain processing speed, regulates inflammation levels and protects the brain as it ages (12). Look for supplements providing krill oil, fish oil, fish liver oil or, especially useful for vegetarians and vegans, algal oil.
  • Phosphatidyl serine is a fat-soluble amino acid found in nerve cell membranes and the myelin sheath that envelopes nerves. It is critical to brain function and neurotransmission – the brain’s communication system. While phosphatidylserine is made within the body, this process can deteriorate as we age (13). Taken as a supplement, phosphatidylserine may therefore help preserve memory and cognitive function: dietary phosphatidyl serine crosses the blood-brain barrier to support memory formation and consolidation, learning, recall, concentration, problem-solving, reflexes and language skills (14).

Amino acids (proteins)

Amino acids provide the building blocks for proteins in the body and in food. The brain’s key messaging chemicals, neurotransmitters, are built from amino acids so it is not surprising that research finds a good intake of a range of these building blocks can support effective brain function.15 Key amino acids for neurotransmitter synthesis include tyrosine, tryptophan, histidine and arginine. A small study found that a supplement of seven amino acids supported improved cognitive flexibility and attention,16 – these were leucine, phenylalanine, isoleucine, histidine, lysine, valine and tryptophan. In addition to providing the raw materials for neurotransmitters, these proteins are thought to support direct maintenance and repair of the brain as well as inhibit the entry of neurotoxic substances.16

Nutrients for brain power: can we supercharge the brain?

Here comes the exciting part! Once we have the essential nutrients in place for normal cognitive function, what more can we do to boost the brain for optimal exam performance? A fast-moving field of research centres on the possibilities offered by herbs and other edible plant extracts that could enhance brain power: so-called “nootropics”. As this set of supplements can contain potent herbal extracts, it’s important to consult your medical or functional practitioner first. With this in mind, let’s take a look at some of the key up-and-coming brain supporters that might improve concentration, learning, memory and recall.


Bacopa Monnieri

Also known as Brahmi and nicknamed “herb of grace”,17 this plant has a long history of traditional use in Ayurvedic medicine for enhancing memory. It is rich in flavonoids, the plant compounds that appear to regulate brain and nervous system inflammation, support the brain’s signalling pathways and improve blood flow to the brain. Bacopa monnieri has performed well to improve language, learning and memory in modern research studies. A 2022 review of nootropic botanicals found that Bacopa monnieri was the plant compound with the biggest effects on memory and learning.18 Another recent study found that Bacopa monnieri could improve higher cognitive processes such as learning rate, memory consolidation and speed of visual information processing.18


Ginkgo biloba (also known as gingko biloba)

Extracts from the leaves of this Chinese plant, known as the “memory plant” and “the world’s oldest living tree” are thought to improve memory-related cognition, including working memory and memory consolidation.18 Studies have found ginkgo biloba may improve cognitive function by dilating blood vessels and boosting the flow of oxygen and nutrients to the brain. The herb also appears to have antioxidant effects, protecting brain and nerve cells from environmental damage.20 A study of young, healthy adults found faster information processing in working memory after taking ginkgo biloba for 30 days.19


Ashwagandha

Ashwagandha is another plant whose roots, leaves and stem have a long history of use in Ayurvedic medicine to support cognition and memory. In recent studies, ashwagandha root extract improved various aspects of learning and memory, including in elderly people with mild cognitive impairment.21


Sage

Part of the mint family of plants, sage has been detailed in traditional medical books for its potential to enhance brain power.19 Sage extracts appear to have ‘cholinergic’ properties, meaning that they can boost the efficiency of the neurotransmitter acetylcholine and improve attention, memory and learning.22 A 2021 study found significant benefits in working memory and accuracy in tests soon after people were given sage extracts.23 Greater improvements were seen after 29 days of supplementation, suggesting that the extracts have a cumulative effect.


Cocoa

Rich in flavonoids, cocoa appears to increase blood flow within the brain and improve other aspects of metabolic health such as insulin sensitivity that can result in better cognitive performance.24,25


Fruit extracts

Many fruits – including berries, grapes and citrus fruits – are known for their anti-inflammatory and antioxidant effects.26 Concentrated extracts may boost the flavonoid content and potential nootropic effects of fruits.27,28 Look out for:


  • Tart cherry for improvements in focus and cognitive function, as well as regulation of sleep cycles. In a trial, Montmorency tart cherry juice improved memory and attention in older adults after 12 weeks.29
  • Blueberry extracts, rich in anti-inflammatory and antioxidant flavonoids known as anthocyanins, may improve short- and long-term memory, as well as spatial memory.30
  • Haskap berry, another anthocyanin-rich fruit, improved memory in older adults and is thought to dilate blood vessels for better flow of oxygen and nutrients to the brain.31

2. Stress-busting supplements that might also help you sleep


Supercharging your brain power is not the only factor to consider when preparing for exams. While short-term stress is a natural response to challenges and might actually help learning, chronic stress can interfere with exam performance by:32


  • Dysregulating hormones and neurotransmitters, which can then impair brain performance, including concentration, memory retrieval and reasoning.32,33
  • Depleting nutrient levels, which risks depriving the brain of the chemical co-factors it needs to function well during revision and exams.34
  • Compromising sleep, which in itself can worsen exam performance.35,36

Let’s look at some key supplements that can help with stress levels and sleep during exam season:


Magnesium

Magnesium levels in the body have long been thought to affect anxiety and mood, primarily through magnesium’s role in regulating the stress response via the hypothalamic-pituitary-adrenal axis.37 Magnesium might also inhibit glutamate, the excitatory neurotransmitter associated with anxiety, fear and panic. Stressful events such as exams can lead to increased excretion of magnesium, potentially worsening feelings of anxiety by dysregulating stress hormones (38). Supplemental magnesium may therefore help to keep stress levels under control.39 Look for a mix of magnesium types such as magnesium taurate, magnesium malate and magnesium citrate.40


B vitamins

The B vitamins, discussed above to support normal brain function, also play an important role in the regulation of the body’s stress response. Look out in particular for the following:


  • Vitamin B5 (pantothenic acid) supports the synthesis and metabolism of cortisol and the production of calming neurotransmitters such as serotonin.41
  • Vitamin B6 also supports the production of the calming neurotransmitters serotonin and GABA.42
  • Studies have found that supplemental magnesium and vitamin B6 work well together to alleviate stress, so teaming these two stress-busting nutrients could be a winning combination for exam season.39,42

Rhodiola

Rhodiola is a herb that has a history of use down the centuries to reduce stress and anxiety.43 Studies have suggested that extracts of Rhodiola rosea:


  • Help with mood, cognition, fatigue, anxiety and stress after three days of use.44
  • Result in lower stress levels after 14 days of use.45
  • Bring immediate improvements in the capacity to cope with stress.46
  • Can combat insomnia.47

Green tea

In studies, participants have reported improved relaxation, mood and anxiety after taking green tea extracts.48 The active constituents of green tea include:


  • Catechins – flavonoids that have shown multiple benefits for cognition in conditions of stress.49
  • L-theanine – an amino acid that can relieve stress. A study of healthy adults found a reported reduction in stress one hour after taking an l-theanine-enriched drink before a stressful cognitive test. Researchers found participants had lower salivary levels of the stress hormone cortisol three hours after the drink.50

One study found significant improvements in stress levels with a combination of green tea, magnesium and rhodiola.51


Ashwagandha

Ashwagandha, already discussed above to support cognitive function, is also used in traditional medicine to help with stress.21 Studies show:


  • A reduction in cortisol and in perceived stress levels.18
  • Improved quantity and quality of sleep.52

Passionflower

Passionflower (Passiflora incarnata) has a long history of use in South America for promoting sleep. Recent studies have confirmed that flavonoids in the leaves and fruit can be effective to:


  • Relieve insomnia by increasing blood levels of the sleep hormone melatonin.53
  • Reduce anxiety and irritability by modulating the brain’s sensitivity to the GABA neurotransmitter.54,55

Key takeaways for how to cope with exam season


If you’re looking for some extra nutritional help to cope with exam season, start by asking yourself where you might get the best improvements.

Firstly, have you got the basics right? If your brain is to work as it should, it will need an adequate intake of the nutrients that support normal cognitive function. Consider:


  • B vitamins
  • Vitamin D
  • Fatty acids
  • Amino acids

Secondly, are you looking for a cognitive boost? Check out the plant extracts that could help your brain to go ‘above and beyond’ – the nootropics – (taking care to consult your medical or functional practitioner in case these powerful herbal concentrates are not suitable for you or your medications):


  • Bacopa monnieri
  • Gingko biloba
  • Ashwagandha
  • Sage
  • Cocoa
  • Fruit extracts

Thirdly, is stress or anxiety likely to disrupt your sleep or interfere with your exam performance? Consider these calming supplements:


  • Magnesium
  • B vitamins
  • Rhodiola
  • Green tea
  • Ashwagandha
  • Passionflower

Here’s to a calm and successful exam season!


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