What are the Best Natural Nootropics and Are They Safe?

Nootropics are ingredients that can boost cognitive functions such as memory, attention, and learning. The word nootropic was coined in 1972 by Romanian scientist Corneliu Giurgea, who paired the Greek words ‘mind’ and ‘bending’. Natural nootropics have soared in popularity in recent years, mirroring the ever-increasing presence of an ‘always on’ culture that often leaves people mentally fatigued. For those new to these supplements we thought it would be a good idea to outline the best natural ingredients and to answer the common question: Are nootropics safe?

The Best Natural Nootropics

The below list is a compilation of some of the best and most heavily researched supplements in this category.


Caffeine is the most widely used nootropic in the world and is naturally found in coffee and tea as well as other botanicals such as guarana, yerba mate and kola nuts.

Caffeine has been subject to hundreds of published research studies and has been shown to increase alertness, combat fatigue and shorten reaction time (1). It is also one of the most effective and widely used sports nutrition supplements (2).

Caffeine works by blocking adenosine. Adenosine is a molecule in the brain which stimulates tiredness (3). Typically, 3-6mg of caffeine per kg of bodyweight is seen as an optimal dose, but some people, especially those sensitive to its effects, will experience a benefit with a lesser amount.

When taken in high doses, caffeine can cause sleep disturbances, nervousness, stomach complaints, nausea and increased heart rate and blood pressure. However, some of these side effects can be attenuated when taken with L-theanine, an ingredient we will explore next.


L-theanine is an amino acid found in Camellia sinensis – the tea plant. In scientific trials, L-theanine has been reported to improve concentration and learning as well as having a calming effect (4). L-theanine is also synergistic with caffeine, as it complements its benefit while helping to ‘level out’ side effects such as nervousness (5).

L-theanine is thought to work by influencing brain alpha-waves, ones that stimulate alertness and mental coordination without affecting calmness (6). L-theanine has shown to be effective at doses as low as 50mg, but typically 150mg-600mg is taken daily. It is recognised as a very safe supplement, as only mild side effects such as headaches have been reported.


Ashwagandha, which is sometimes referred to as Indian ginseng or its botanical name Withania somnifera, is a stalwart of ayurvedic medicine. It is classed as an adaptogen as it helps the body deal with mental and physical stressors. The research is strong with regards to its ability to decrease cortisol (the stress hormone) as well as depression and anxiety (7).

Investigations have also shown that it can help sleep quality, exercise performance, fertility in men and libido in men and women (8,9,10,11). The most effective type of Ashwagandha is the patented KSM-66® which provides 5% withanolides – the active ingredients. 300mg taken twice per day appears to be the optimal dose of KSM-66®. Ashwagandha is also recognised as a safe supplement, with very few side effects reported.

Rhodiola rosea

Also known as golden root, Rhodiola is a well-researched adaptogen which has been shown to have similar benefits to Ashwagandha. Published research indicates large benefits to stress levels, mood and anxiousness, with the biggest effect in those who are highly stressed (12). It has also been found to help exercise performance by reducing perceived exertion (13). Other benefits include curbing appetite and episodes of binge eating (14).

Benefits have been noticed at doses as low as 50mg, but the current evidence suggests that 400mg per day is optimal. Unfortunately many of the supplements on the market have been found to contain much less Rhodiola than advertised, so make sure to choose a reputable brand. Thankfully, Rhodiola appears to be safe, but those on anti-depressants should speak with their GP before starting supplementation.

Korean Ginseng

Otherwise known as Panax or true ginseng, Korean ginseng has long been used in traditional Chinese medicine. Like Rhodiola and Ashwagandha, it is also classed as an adaptogen. Studies into Korean ginseng have shown that it can decrease mental and physical fatigue, improve mental health, cognitive ability and perceived quality of life (15,16). It has also been found to help the immune system, blood glucose regulation and erectile function in men (17,18,19).

The benefits are due to the ginsenosides content of the plant. When looking for the best supplement, look for an organic root extract as this will have the highest percentage of ginsenosides. Typically, 200-400mg of root extract is a good amount to aim for daily. Korean ginseng is safe for most people, but those on blood pressure or diabetes medication should consult their GP before supplementation. It can also cause sleep disturbances and increases heart rate.

Ginkgo Biloba

Ginkgo Biloba is one of the most popular herbals supplements in the world. Extracts are taken from the leaves as these have the highest concentration of flavone glycosides and terpene lactones – the active ingredients.

Ginkgo Biloba leaf supplements have been shown to improve brain blood flow, which is thought to be the reason why it can improve memory and mental processing, especially in older adults (20,21). Typically, 120mg of ginkgo biloba extract is recommended up to three times daily. The most heavily researched type is known as EGb 761 which is standardised to contain 24% flavone glycosides and 6% terpene lactones (22).

Ginkgo biloba is also a safe supplement for the vast majority of people but minor side effects such as stomach upset, headache, dizziness, constipation, heart palpitations and allergic skin reactions have been noted. As it can increase the effects of blood thinning medication it should not be taken alongside anti-coagulants.

Omega 3 Fish Oil

Omega 3 fish oil is typically sourced from sardines and anchovies, oily fish which are low in mercury and other pollutants. Oily fish are famously referred to as ‘brain food’ as they contain the long chain omega 3 fatty acid docosahexaenoic acid (DHA) as well as eicosapentaenoic acid (EPA).

DHA is one of the most prominent phospholipids in the brain and is essential for cognitive function. Alongside EPA, it has neuroprotective properties and is effective at reducing symptoms of anxiety and depression as well as helping those with bipolar disorder (23,24,25).

It is also important for pregnant and breastfeeding women to help with child brain and eye development. The European Food Safety Authority recommends 250mg of DHA per day for the “maintenance of normal brain function” (26). However, research studies have typically used a fish oil that provides 750-1200mg of DHA as well as a similar amount of EPA.

Fish oil is generally a safe supplement, but care needs to be taken if you are on anti-coagulants as it can accentuate their effect. Obviously those with a fish allergy should avoid supplementation. Side effects tend to be mild and are mostly related to gastrointestinal complaints.

Bacopa monnieri

Like Ashwagandha, Bacopa monnieri (also known as Brahmi) is a cornerstone of Ayurveda. Although not as well-known or as heavily researched in the west, studies have shown that it can improve information processing speed and memory formation as well as reduce symptoms of mild anxiety (27,28). The active ingredients known as bacosides are the reason for its nootropic benefits. These saponins are thought to influence the hippocampus, the part of the brain that has a major role in learning and memory (29).

Research shows that taking 300-600mg of a bacopa extract (at least 30% bacosides) can be beneficial within 4-6 weeks, but 8-12 weeks is needed to experience the full effects. Bacopa monnieri should be taken with a meal for two key reasons. Firstly, it is fat-soluble, meaning it needs to be consumed with fat for optimal absorption. Secondly, there are reports of stomach upset when taken on an empty stomach. Thankfully, there aren’t any other known side effects or interactions.


Like DHA, Phosphatidylserine is an important phospholipid and in the brain it is incorporated into cell membranes where it helps cell structure and signalling (30). Although the body can produce some naturally and get it from some foods (fish is a particularly good source), supplementation provides heightened benefits. Specifically, studies have shown that it can improve attention span, and cognitive function while having anti-stress and neuroprotective properties (31,32,33,34).

As low as 100mg of phosphatidylserine per day has shown to be beneficial, but most studies suggest that 300-600mg daily is an amount that provides the best nootropic benefits. Up to 600mg daily has been shown to cause no notable side effects (35). However as many phoshatidylserine supplements are sourced from soy, they should be avoided by soy allergy sufferers.

Acetyl L-Carnitine

L-carnitine is produced in the liver and kidneys by the amino acids lysine and methionine. Carnitine is needed by all cells in the body to breakdown fatty acids for energy. When acetylated, it crosses the blood-brain barrier more easily where it helps to support brain energy metabolism and the synthesis of acetylcholine and other neurotransmitters (36,37). It also has anti-inflammatory and antioxidant benefits which are known to help protect brain cells (38).

Typically, 500-3000mg per day is recommended for those supplementing with acetyl l-carnitine. Supplements are generally well tolerated, with few side effects reported.

Lions’ Mane

Lion’s mane (Hericium erinaceus) is a medicinal mushroom that has exciting brain boosting properties. Research has shown that it stimulates Nerve Growth Factor which is a key regulator of neurons (39). It can also stimulate the production of myelin sheath which encase and protect nerve cells (40). These mechanisms are thought to be the reason why studies have shown that it can improve brain function in those with cognitive impairment as well as helping those with anxiety and depression (41,42).

As there have been relatively few studies on Lion’s Mane, it is currently unknown what the optimal dose is. However 250-750mg of a fruiting body extract with high % of polysaccharides and beta-glucans would be a good place to start. There are no major side effects from Lion’s Mane so it’s viewed as a safe nootropic.


Creatine is arguably the most researched supplement in the world. It has been popular for decades with athletes as it can improve muscle size, strength and endurance (43,44).

However, it is now appreciated as a nootropic given its ability to fight mental fatigue and support cognitive functioning. It has also shown promise in combination with selective serotonin reuptake inhibitors (SSRIs) for those with depression (45). Creatine is most effective in vegans and vegetarians who get little through their diet (46).

Creatine works by regenerating adenosine triphosphate (ATP) which fuels every cell in the body, including those the brain. With regards to dosing, we can confidently say that 5-10g per day should be taken for best benefit. This should ideally be taken alongside a carbohydrate source as the subsequent increase in insulin levels helps shuttle creatine into the cells where it is stored as phosphocreatine (47).

Creatine is a very safe supplement that has very few side effects or interactions.


Hopefully this article has helped you understand a bit more about some of the best natural brain boosters available and put your mind at rest about any potential side effects. However if you are still unsure about natural nootropics and would like more information, the team here at Brainpower Nootropics are always happy to help.