A Solution for Brain Fog
April 2022 Issue

A Solution for Brain Fog

Two plant extracts restore mental clarity, energy, and focus. Scientifically reviewed by: Dr. Gary Gonzalez, MD, on February 2022. Written By Lisa Tanner.

We all have moments when we feel mentally fatigued and find it hard to concentrate. This is often referred to as brain fog.

Until recently, it was believed that little could be done about it.

But by studying various medical conditions associated with brain fog, scientists have pinpointed biological alterations in the brain that may cause these feelings of decreased mental energy and sharpness.1-7

This research has allowed for the identification of two plant-based nutrients that can prevent or potentially even reverse these alterations to bring back mental clarity, energy, and focus.

In clinical studies, mango leaf extract containing the compound mangiferin improves reaction time, reduces mental fatigue, and boosts attention, performance accuracy, and working memory.8,9

In additional clinical studies, peppermint oil significantly reduces the development of mental fatigue and improvesaspects of attention and memory.10

These two ingredients can help to lift the clouds of brain fog and restore mental energy, clarity, focus, and performance.

What Is Brain Fog?

Brain having red focus area with decreased cognitive performance

Brain fog refers to a general feeling of decreased mental energy and focus. It may be characterized by mental fatigue and clouding, forgetfulness, fuzzy thinking, confusion, and difficulty concentrating.

It’s more than an annoyance. It can also decrease cognitive performance and hinder the ability to get work done or accomplish goals.

Scientists trying to understand brain fog noted certain medical conditions associated with some of the same mental symptoms.

For example, people with allergies, inflammatory disorders, and dietary sensitivities often complain of brain fog.1-7 Over 90% of patients with mast cell disorders, which increase inflammation, report frequent cognitive impairmentconsistent with brain fog.2

Even seasonal allergies can lead to reduced cognitive performance, including impaired attention, memory problems, and reduced speed of information processing.1

These observations led scientists to propose that brain fog may be caused by several related mechanisms. These include the release of histamine (the chemical that causes allergic symptoms), inflammation, neurotransmitter imbalance, and impairments in neuronal activity.1-3

Plant Extracts That Help

Woman rubbing temples and staring at laptop finding trouble focusing through brain fog

When researchers set out to find compounds that could alleviate brain fog, they looked for ingredients that met two criteria:

  • They had a track record in animal or human studies of improving the symptoms of brain fog, like aspects of cognition.
  • They targeted the possible causes of brain fog, by reducing neuroinflammation, histamine modulation, balancing neuro-transmitters, or neuronal activity support.

They found two plant-derived ingredients that were the most promising: mango leaf extract and peppermint oil.

Mangiferin Boosts Brain Power

Mango leaves, extracts, and teas have long been used in Asian and African countries to treat a range of disorders, including fatigue and exhaustion.

More recently, scientists found that mango leaf extracts have neuroprotective, anti-inflammatory, and anti-diabetic properties.8

Mangiferin is a compound found in mango leaves that is believed to be largely responsible for these effects.

In animal models, mangiferin helps protect the brain by reducing oxidative stress and neuroinflammation and by providing neurotransmitter support.11-13

Animal studies have also found that mangiferin prevents cognitive impairment and memory impairments, symptoms of brain fog.14 In addition, in mice and rat studies, mangiferin was shown to have favorable anti-allergic properties15,16This further suggests benefits against brain fog in those with allergies.

More recently, human trials have explored the use of mangiferin-containing extracts in treating symptoms consistent with brain fog.

One study randomized healthy adults into four groups. One group took a mango leaf extract containing 60% mangiferin, one took caffeine, one was given a combination of mangiferin and caffeine, and one received a placebo.8

The mango leaf extract led to a remarkable 47% improvement in fatigue compared to baseline. It also led to an almost 5% improvement in reaction time compared to baseline, which was a significant improvement compared to the placebo group. This was a greater improvement than seen with caffeine alone or the combination of caffeine and mangiferin.

Tests of electrical activity in the brain showed that those taking mangiferin had increased activity in regions associated with complex cognitive processing, attention, and memory.

In another clinical study, healthy young adults were given either 300 mg of the mangiferin-containing mango leaf extract or a placebo.9 In tests, the extract improved specific areas of cognitive function, including aspects of attention, performance accuracy, and working memory.

These improvements were accompanied by a more relaxed mood. This is notable because many people who take caffeine to counter brain fog complain that it reduces relaxation and increases nervousness and jitters.


Lab researcher looking through microscope to study mango leaf extract for mental symptoms

Banish Brain Fog

  • Brain fog is a constellation of symptoms that cloud mental function, including reduced mental energy, clarity, focus, and performance.
  • Scientists have found clues that inflammation, histamine release, and neurotransmitter imbalances may contribute to brain fog.
  • Mango leaf extract and peppermint oil may help prevent or reverse these potential causes of brain fog.
  • Human studies have found that peppermint oil and mango leaf extract containing the active compound mangiferin each improve aspects of cognition associated with brain fog, including attention, memory, and cognitive performance.
  • These two ingredients help combat brain fog and bring back mental focus, attention, energy, and sharpness.

Peppermint Sharpens the Mind

The herb peppermint has been traditionally used for its medicinal properties, including as a digestive aid and to promote calming. Its oil contains a high concentration of monoterpene compounds, including menthol and menthone.

Studies have shown that plants rich in monoterpenes have cognitive benefits.17,18 For example, peppermint teas have been shown to improve memory and mental alertness in human subjects.19

Mint species have demonstrated the ability to modulate various neurotransmitters in the brain, such as acetylcholine and GABA, which play roles in cognition, mood, and mental alertness.10

In a clinical trial, researchers randomized healthy adults to receive either peppermint oil containing 60% monoterpenes or a placebo, and tested various aspects of memory, attention, and mood.10

The peppermint oil significantly reduced the development of mental fatigue and improved aspects of attention and working memory. By contrast, those receiving the placebo were severely fatigued within a few hours after the various demanding cognitive tasks.

Peppermint oil and mango leaf extract can help lift brain fog and bring back mental clarity, energy, and focus.


Woman and man discussing work progress through improved cognitive performance

Brain fog refers to symptoms of reduced mental energy, clarity, focus, and performance.

Research suggests that neuroinflammation, histamine release, and neurotransmitter imbalances can contribute to the development of brain fog symptoms.

Two plant-derived nutrients may help combat brain fog. Preclinical studies show that mangiferinfrom mango leaf extract and peppermint oil address the mechanisms thought to contribute to brain fog.

Human studies of mangiferin and peppermint oil show that they improve various aspects of brain fog, reducing mental fatigue and improving attention, memory, and cognitive performance.

A combination of these two ingredients may maximize the brain-supporting power of these nutrients and help lift brain fog.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.


  1. Hartgerink-Lutgens I, Vermeeren A, Vuurman E, et al. Disturbed cognitivefunctions after nasal provocation in patients with seasonal allergicrhinitis. Clin Exp Allergy. 2009 Apr;39(4):500-8.
  2. Theoharides TC, Stewart JM, Hatziagelaki E, et al. Brain “fog,”inflammation and obesity: key aspects of neuropsychiatric disordersimproved by luteolin. Front Neurosci. 2015;9:225.
  3. Balter LJ, Bosch JA, Aldred S, et al. Selective effects of acute low-gradeinflammation on human visual attention. Neuroimage. 2019 Nov15;202:116098.
  4. Akin C. Mast cell activation syndromes. J Allergy Clin Immunol. 2017 Aug;140(2):349-55.
  5. Croall ID, Hoggard N, Aziz I, et al. Brain fog and non-coeliac glutensensitivity: Proof of concept brain MRI pilot study. PLoS One.2020;15(8):e0238283.
  6. Makhlouf S, Messelmani M, Zaouali J, et al. Cognitive impairment in celiacdisease and non-celiac gluten sensitivity: review of literature on the main cognitive impairments, the imaging and the effect of gluten free diet. Acta Neurol Belg. 2018 Mar;118(1):21-7.
  7. Yelland GW. Gluten-induced cognitive impairment (“brain fog”)
    in coeliac disease. J Gastroenterol Hepatol. 2017 Mar;32 Suppl1:90-3.
  8. Lopez-Rios L, Wiebe JC, Vega-Morales T, et al. Central nervous systemactivities of extract Mangifera indica L. J Ethnopharmacol. 2020Oct 5;260:112996.
  9. Wightman EL, Jackson PA, Forster J, et al. Acute Effects of aPolyphenol-Rich Leaf Extract of Mangifera indica L. (Zynamite) on CognitiveFunction in Healthy Adults: A Double-Blind, Placebo-Controlled CrossoverStudy.Nutrients. 2020 Jul 23;12(8).
  10. Kennedy D, Okello E, Chazot P, et al. Volatile Terpenes and Brain Function:Investigation of the Cognitive and Mood Effects of Mentha x Piperita L.Essential Oil with In Vitro Properties Relevant to Central Nervous SystemFunction. Nutrients. 2018 Aug 7;10(8).
  11. Jangra A, Arora MK, Kisku A, et al. The multifaceted role of mangiferin inhealth and diseases: a review. Avc Tradit Med (ADTM).2021;21:619-43.
  12. Feng ST, Wang ZZ, Yuan YH, et al. Mangiferin: A multipotent natural product preventing neurodegeneration in Alzheimer’s and Parkinson’s disease models. Pharmacol Res. 2019 Aug;146:104336.
  13. Marquez L, Garcia-Bueno B, Madrigal JL, et al. Mangiferin decreases inflammation and oxidative damage in rat brain after stress. Eur J Nutr. 2012 Sep;51(6):729-39.
  14. Lum PT, Sekar M, Gan SH, et al. Protective effect of mangiferin on memoryimpairment: A systematic review. Saudi J Biol Sci. 2021Jan;28(1):917-27.
  15. Sekar M. Molecules of Interest–Mangiferin–A Review. Annual Research & Review in Biology. 2015 01/10;5(4):307-20.
  16. Garcia D, Escalante M, Delgado R, et al. Anthelminthic and antiallergicactivities of Mangifera indica L. stem bark components Vimang andmangiferin. Phytother Res. 2003 Dec;17(10):1203-8.
  17. Falcone PH, Nieman KM, Tribby AC, et al. The attention-enhancing effects ofspearmint extract supplementation in healthy men and women: a randomized,double-blind, placebo-controlled, parallel trial. Nutr Res.2019Apr;64:24-38.
  18. Falcone PH, Tribby AC, Vogel RM, et al. Efficacy of a nootropic spearmintextract on reactive agility: a randomized, double-blind,placebo-controlled, parallel trial. J Int Soc Sports Nutr. 2018Dec 12;15(1):58.
  19. Moss M, Jones R, Moss L, et al. Acute consumption of peppermint andchamomile teas produce contrasting effects on cogntion and mood in healthyyoung adults. Plant Science Today. 2016;3(3):